2day_Python_Basic.ipynb

{
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  {
   "cell_type": "markdown",
   "id": "0dd2def5-7840-4f86-91e5-0370a02e0937",
   "metadata": {},
   "source": [
    "# Pandas"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "3c766dd5-dff6-4aed-bb71-44da5b386c47",
   "metadata": {},
   "source": [
    "1D-Array : 1차원 배열\n",
    "\n",
    "Series : 인덱스와 컬럼을 포함한 1차원 데이터\n",
    "\n",
    "DataFrame : 시리즈가 여러 개 모인, 2차원 이상의 데이터"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "e32684ad-221e-4653-91e9-fc6afc764c42",
   "metadata": {},
   "source": [
    "## DataFrame 생성"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "id": "fd41a03d-c01b-4ace-be4a-7628d27a80d6",
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    {
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       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>학번</th>\n",
       "      <th>성적</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>2000</td>\n",
       "      <td>85</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2001</td>\n",
       "      <td>95</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>2002</td>\n",
       "      <td>75</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>2003</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>2004</td>\n",
       "      <td>100</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>2005</td>\n",
       "      <td>100</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>2006</td>\n",
       "      <td>95</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>2007</td>\n",
       "      <td>85</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>2008</td>\n",
       "      <td>80</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>2009</td>\n",
       "      <td>85</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     학번   성적\n",
       "0  2000   85\n",
       "1  2001   95\n",
       "2  2002   75\n",
       "3  2003   70\n",
       "4  2004  100\n",
       "5  2005  100\n",
       "6  2006   95\n",
       "7  2007   85\n",
       "8  2008   80\n",
       "9  2009   85"
      ]
     },
     "execution_count": 1,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "data = {'학번':range(2000, 2010),\n",
    "        '성적':[85, 95, 75, 70, 100, 100, 95, 85, 80 ,85]}\n",
    "df = pd.DataFrame(data)\n",
    "df"
   ]
  },
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   "execution_count": 2,
   "id": "a2405d2c-ab77-42a6-8f66-2eef2b42e345",
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    {
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>성적</th>\n",
       "      <th>학번</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>85</td>\n",
       "      <td>2000</td>\n",
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       "      <th>1</th>\n",
       "      <td>95</td>\n",
       "      <td>2001</td>\n",
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       "      <th>2</th>\n",
       "      <td>75</td>\n",
       "      <td>2002</td>\n",
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       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>70</td>\n",
       "      <td>2003</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>100</td>\n",
       "      <td>2004</td>\n",
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       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>100</td>\n",
       "      <td>2005</td>\n",
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       "      <th>6</th>\n",
       "      <td>95</td>\n",
       "      <td>2006</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>85</td>\n",
       "      <td>2007</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>80</td>\n",
       "      <td>2008</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>85</td>\n",
       "      <td>2009</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
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       "</div>"
      ],
      "text/plain": [
       "    성적    학번\n",
       "0   85  2000\n",
       "1   95  2001\n",
       "2   75  2002\n",
       "3   70  2003\n",
       "4  100  2004\n",
       "5  100  2005\n",
       "6   95  2006\n",
       "7   85  2007\n",
       "8   80  2008\n",
       "9   85  2009"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# columns=['컬럼명'] 으로 컬럼 순서 조작 가능\n",
    "df = pd.DataFrame(data, columns=['성적', '학번'])\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 142,
   "id": "c056d2f4-47b1-43bf-a07d-91d09d241b6c",
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   "outputs": [
    {
     "data": {
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       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
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       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "      <td>20210204</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "      <td>NaN</td>\n",
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       "      <th>20210201</th>\n",
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       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "      <td>NaN</td>\n",
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       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
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       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
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       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
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       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "      <td>NaN</td>\n",
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       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210228</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>오빈</td>\n",
       "      <td>216</td>\n",
       "      <td>236</td>\n",
       "      <td>20210303</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210228</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>양평</td>\n",
       "      <td>3299</td>\n",
       "      <td>3187</td>\n",
       "      <td>20210303</td>\n",
       "      <td>NaN</td>\n",
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       "    <tr>\n",
       "      <th>20210228</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>원덕</td>\n",
       "      <td>322</td>\n",
       "      <td>304</td>\n",
       "      <td>20210303</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210228</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1899</td>\n",
       "      <td>1716</td>\n",
       "      <td>20210303</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210228</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>30</td>\n",
       "      <td>31</td>\n",
       "      <td>20210303</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>16751 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "         사용일자  노선명    역명  승차총승객수    하차총승객수  등록일자\n",
       "20210201  중앙선   용문  1282    1259  20210204   NaN\n",
       "20210201  중앙선   지평    48      43  20210204   NaN\n",
       "20210201  중앙선   아신   415     413  20210204   NaN\n",
       "20210201  중앙선   양수  1463    1466  20210204   NaN\n",
       "20210201  중앙선  운길산   495     463  20210204   NaN\n",
       "...       ...  ...   ...     ...       ...   ...\n",
       "20210228  중앙선   오빈   216     236  20210303   NaN\n",
       "20210228  중앙선   양평  3299    3187  20210303   NaN\n",
       "20210228  중앙선   원덕   322     304  20210303   NaN\n",
       "20210228  중앙선   용문  1899    1716  20210303   NaN\n",
       "20210228  중앙선   지평    30      31  20210303   NaN\n",
       "\n",
       "[16751 rows x 6 columns]"
      ]
     },
     "execution_count": 142,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# csv 파일 불러오기\n",
    "data = pd.read_csv('CARD_SUBWAY_MONTH_202102.txt')\n",
    "data"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 149,
   "id": "1dfb49b9-a827-4abd-8c6f-795293256635",
   "metadata": {},
   "outputs": [],
   "source": [
    "# 실습 파일 .txt 로 받아서 .csv로 변환하기\n",
    "# new_csv_file = data.to_csv('CARD_SUBWAY_MONTH_202102.csv')\n",
    "\n",
    "# 근데 변환이 이상하게 되네..\n",
    "# encoding 아래와 같이 인자 주면 해결됨\n",
    "\n",
    "# new_csv_file = data.to_csv('CARD_SUBWAY_MONTH_202102_new.csv', encoding = 'euc-kr')\n",
    "\n",
    "# 근데도 깔끔하게 안 되네.. "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 139,
   "id": "a79d240a-ae99-47dd-9e4f-be6fa3ce8171",
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    {
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       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
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       "      <th>0</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
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       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
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       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
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       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
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       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
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       "      <th>...</th>\n",
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       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
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       "    <tr>\n",
       "      <th>16746</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>오빈</td>\n",
       "      <td>216</td>\n",
       "      <td>236</td>\n",
       "      <td>20210303</td>\n",
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       "    <tr>\n",
       "      <th>16747</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양평</td>\n",
       "      <td>3299</td>\n",
       "      <td>3187</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16748</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>원덕</td>\n",
       "      <td>322</td>\n",
       "      <td>304</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16749</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1899</td>\n",
       "      <td>1716</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16750</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>30</td>\n",
       "      <td>31</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>16751 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "0      20210201  중앙선   용문    1282    1259  20210204\n",
       "1      20210201  중앙선   지평      48      43  20210204\n",
       "2      20210201  중앙선   아신     415     413  20210204\n",
       "3      20210201  중앙선   양수    1463    1466  20210204\n",
       "4      20210201  중앙선  운길산     495     463  20210204\n",
       "...         ...  ...  ...     ...     ...       ...\n",
       "16746  20210228  중앙선   오빈     216     236  20210303\n",
       "16747  20210228  중앙선   양평    3299    3187  20210303\n",
       "16748  20210228  중앙선   원덕     322     304  20210303\n",
       "16749  20210228  중앙선   용문    1899    1716  20210303\n",
       "16750  20210228  중앙선   지평      30      31  20210303\n",
       "\n",
       "[16751 rows x 6 columns]"
      ]
     },
     "execution_count": 139,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# read() 함수는 첫 열을 인덱스로 인식하기 때문에, 인덱스를 따로 지정해줘야 하는 경우\n",
    "# 인덱스 컬럼을 포함하지 않고 있음을 인자에 넣어줘야함\n",
    "data = pd.read_csv('CARD_SUBWAY_MONTH_202102.txt', index_col=False)\n",
    "df = data\n",
    "df"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "1cbac8e5-48b2-4c17-b44d-137984cb1e84",
   "metadata": {},
   "source": [
    "## 탐색"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 52,
   "id": "067ee55b-10b6-43e7-a9ec-5e9219278e37",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "0  20210201  중앙선   용문    1282    1259  20210204\n",
       "1  20210201  중앙선   지평      48      43  20210204\n",
       "2  20210201  중앙선   아신     415     413  20210204\n",
       "3  20210201  중앙선   양수    1463    1466  20210204\n",
       "4  20210201  중앙선  운길산     495     463  20210204"
      ]
     },
     "execution_count": 52,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 위에서부터 인자 값만큼 출력\n",
    "df.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 53,
   "id": "6792c4e5-2410-434c-b26f-23f447f7325c",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(16751, 6)"
      ]
     },
     "execution_count": 53,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 데이터프레임이 몇 차원으로 구성된지 확인\n",
    "df.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 54,
   "id": "c146fd9a-42e8-4015-99cb-3bfeeac5a7a7",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>count</th>\n",
       "      <td>1.675100e+04</td>\n",
       "      <td>16751.000000</td>\n",
       "      <td>16751.000000</td>\n",
       "      <td>1.675100e+04</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>mean</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8567.344696</td>\n",
       "      <td>8536.474419</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>std</th>\n",
       "      <td>8.083073e+00</td>\n",
       "      <td>9006.651687</td>\n",
       "      <td>9064.054078</td>\n",
       "      <td>2.749315e+01</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>min</th>\n",
       "      <td>2.021020e+07</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>2.021020e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25%</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>2652.500000</td>\n",
       "      <td>2594.500000</td>\n",
       "      <td>2.021021e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50%</th>\n",
       "      <td>2.021022e+07</td>\n",
       "      <td>5857.000000</td>\n",
       "      <td>5733.000000</td>\n",
       "      <td>2.021022e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>75%</th>\n",
       "      <td>2.021022e+07</td>\n",
       "      <td>11257.000000</td>\n",
       "      <td>11117.000000</td>\n",
       "      <td>2.021022e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>max</th>\n",
       "      <td>2.021023e+07</td>\n",
       "      <td>88904.000000</td>\n",
       "      <td>87891.000000</td>\n",
       "      <td>2.021030e+07</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "               사용일자        승차총승객수        하차총승객수          등록일자\n",
       "count  1.675100e+04  16751.000000  16751.000000  1.675100e+04\n",
       "mean   2.021021e+07   8567.344696   8536.474419  2.021023e+07\n",
       "std    8.083073e+00   9006.651687   9064.054078  2.749315e+01\n",
       "min    2.021020e+07      1.000000      0.000000  2.021020e+07\n",
       "25%    2.021021e+07   2652.500000   2594.500000  2.021021e+07\n",
       "50%    2.021022e+07   5857.000000   5733.000000  2.021022e+07\n",
       "75%    2.021022e+07  11257.000000  11117.000000  2.021022e+07\n",
       "max    2.021023e+07  88904.000000  87891.000000  2.021030e+07"
      ]
     },
     "execution_count": 54,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 데이터프레임의 기본통계지표 확인\n",
    "df.describe()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 55,
   "id": "4a60c507-9a49-4b5f-a75f-10543df2954b",
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "<class 'pandas.core.frame.DataFrame'>\n",
      "RangeIndex: 16751 entries, 0 to 16750\n",
      "Data columns (total 6 columns):\n",
      " #   Column  Non-Null Count  Dtype \n",
      "---  ------  --------------  ----- \n",
      " 0   사용일자    16751 non-null  int64 \n",
      " 1   노선명     16751 non-null  object\n",
      " 2   역명      16751 non-null  object\n",
      " 3   승차총승객수  16751 non-null  int64 \n",
      " 4   하차총승객수  16751 non-null  int64 \n",
      " 5   등록일자    16751 non-null  int64 \n",
      "dtypes: int64(4), object(2)\n",
      "memory usage: 785.3+ KB\n"
     ]
    }
   ],
   "source": [
    "# 각 컬럼의 수와, 데이터 타입, null 포함 여부 확인\n",
    "df.info()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "63197660-f56e-4580-a600-c83dc6d8513f",
   "metadata": {},
   "source": [
    "날짜와 관련된 데이터의 경우, 데이터프레임에 담기면 Datatype이 int64일 수 있는데,\n",
    "이런 경우는 직접 형변환을 하여 전처리 진행"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 56,
   "id": "ba455880-9966-42e0-9e78-ff677348a8c2",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array(['중앙선', '장항선', '일산선', '우이신설선', '안산선', '수인선', '분당선', '과천선',\n",
       "       '공항철도 1호선', '경춘선', '경인선', '경의선', '경원선', '경부선', '경강선', '9호선2~3단계',\n",
       "       '9호선', '8호선', '7호선', '6호선', '5호선', '4호선', '3호선', '2호선', '1호선'],\n",
       "      dtype=object)"
      ]
     },
     "execution_count": 56,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 특정 칼럼에서 중복값 제거하고 출력\n",
    "# 유일값 찾기\n",
    "df['노선명'].unique()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 57,
   "id": "2f5810ec-1e4e-4c84-a04c-afd688012629",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "5호선         1484\n",
       "7호선         1428\n",
       "2호선         1400\n",
       "경부선         1092\n",
       "6호선         1051\n",
       "분당선          967\n",
       "3호선          937\n",
       "경원선          821\n",
       "경의선          737\n",
       "4호선          728\n",
       "9호선          700\n",
       "중앙선          588\n",
       "경인선          560\n",
       "경춘선          532\n",
       "수인선          504\n",
       "8호선          476\n",
       "공항철도 1호선     392\n",
       "9호선2~3단계     364\n",
       "안산선          364\n",
       "우이신설선        364\n",
       "경강선          308\n",
       "일산선          282\n",
       "1호선          280\n",
       "과천선          224\n",
       "장항선          168\n",
       "Name: 노선명, dtype: int64"
      ]
     },
     "execution_count": 57,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 각 데이터가 몇 개씩 있는지 확인\n",
    "df['노선명'].value_counts()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "b563e4cd-ee68-40cf-93db-2dd110d0569e",
   "metadata": {},
   "source": [
    "## 정렬"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 58,
   "id": "9dc284f5-7d68-4a70-8846-96180420c5f3",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
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       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>14984</th>\n",
       "      <td>20210226</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>88904</td>\n",
       "      <td>87891</td>\n",
       "      <td>20210301</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10857</th>\n",
       "      <td>20210219</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>86800</td>\n",
       "      <td>80948</td>\n",
       "      <td>20210222</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13705</th>\n",
       "      <td>20210223</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>84922</td>\n",
       "      <td>83364</td>\n",
       "      <td>20210226</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14314</th>\n",
       "      <td>20210224</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>84628</td>\n",
       "      <td>82667</td>\n",
       "      <td>20210227</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14384</th>\n",
       "      <td>20210225</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>84374</td>\n",
       "      <td>82960</td>\n",
       "      <td>20210228</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14346</th>\n",
       "      <td>20210224</td>\n",
       "      <td>일산선</td>\n",
       "      <td>지축</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>20210227</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4853</th>\n",
       "      <td>20210209</td>\n",
       "      <td>분당선</td>\n",
       "      <td>복정</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>20210212</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14425</th>\n",
       "      <td>20210225</td>\n",
       "      <td>3호선</td>\n",
       "      <td>충무로</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>20210228</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10025</th>\n",
       "      <td>20210217</td>\n",
       "      <td>경의선</td>\n",
       "      <td>김포공항</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>20210220</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13752</th>\n",
       "      <td>20210224</td>\n",
       "      <td>3호선</td>\n",
       "      <td>충무로</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>20210227</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>16751 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명    역명  승차총승객수  하차총승객수      등록일자\n",
       "14984  20210226  2호선    강남   88904   87891  20210301\n",
       "10857  20210219  2호선    강남   86800   80948  20210222\n",
       "13705  20210223  2호선    강남   84922   83364  20210226\n",
       "14314  20210224  2호선    강남   84628   82667  20210227\n",
       "14384  20210225  2호선    강남   84374   82960  20210228\n",
       "...         ...  ...   ...     ...     ...       ...\n",
       "14346  20210224  일산선    지축       1       0  20210227\n",
       "4853   20210209  분당선    복정       1       0  20210212\n",
       "14425  20210225  3호선   충무로       1       0  20210228\n",
       "10025  20210217  경의선  김포공항       1       0  20210220\n",
       "13752  20210224  3호선   충무로       1       0  20210227\n",
       "\n",
       "[16751 rows x 6 columns]"
      ]
     },
     "execution_count": 58,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 특정 컬럼 기준으로 데이터 정렬\n",
    "# ascending= 인자는 디폴트값으로 오름차순, False를 주면 내림차순으로 정렬\n",
    "# asc, desc\n",
    "df.sort_values(by=['승차총승객수'],ascending=False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 59,
   "id": "50481dce-ba7e-4adb-9804-b64c7e3bbd54",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>16750</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>30</td>\n",
       "      <td>31</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16749</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1899</td>\n",
       "      <td>1716</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16748</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>원덕</td>\n",
       "      <td>322</td>\n",
       "      <td>304</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16747</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양평</td>\n",
       "      <td>3299</td>\n",
       "      <td>3187</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16746</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>오빈</td>\n",
       "      <td>216</td>\n",
       "      <td>236</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>16751 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "16750  20210228  중앙선   지평      30      31  20210303\n",
       "16749  20210228  중앙선   용문    1899    1716  20210303\n",
       "16748  20210228  중앙선   원덕     322     304  20210303\n",
       "16747  20210228  중앙선   양평    3299    3187  20210303\n",
       "16746  20210228  중앙선   오빈     216     236  20210303\n",
       "...         ...  ...  ...     ...     ...       ...\n",
       "4      20210201  중앙선  운길산     495     463  20210204\n",
       "3      20210201  중앙선   양수    1463    1466  20210204\n",
       "2      20210201  중앙선   아신     415     413  20210204\n",
       "1      20210201  중앙선   지평      48      43  20210204\n",
       "0      20210201  중앙선   용문    1282    1259  20210204\n",
       "\n",
       "[16751 rows x 6 columns]"
      ]
     },
     "execution_count": 59,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 기본적으로 데이터들은 인덱스를 기준으로 정렬되어 있지만,\n",
    "# 그렇지 않은 경우 인덱스를 기준으로 재정렬이 필요함\n",
    "# 아래 코드는 인덱스 역정렬이 필요한 경우\n",
    "df.sort_index(ascending=False)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "9b500008-447e-4c30-9010-c933c6600f0d",
   "metadata": {},
   "source": [
    "## 선택"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 60,
   "id": "34f7e42c-0dc8-403d-b6a5-2f45341e6b06",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0        중앙선\n",
       "1        중앙선\n",
       "2        중앙선\n",
       "3        중앙선\n",
       "4        중앙선\n",
       "        ... \n",
       "16746    중앙선\n",
       "16747    중앙선\n",
       "16748    중앙선\n",
       "16749    중앙선\n",
       "16750    중앙선\n",
       "Name: 노선명, Length: 16751, dtype: object"
      ]
     },
     "execution_count": 60,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 컬럼명으로 선택\n",
    "df['노선명']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 61,
   "id": "ead7c193-08cb-4760-8596-2c0c03407ffe",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "\n",
       "    .dataframe tbody tr th {\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>팔당</td>\n",
       "      <td>687</td>\n",
       "      <td>662</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>도심</td>\n",
       "      <td>2237</td>\n",
       "      <td>1736</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>덕소</td>\n",
       "      <td>5139</td>\n",
       "      <td>5082</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양정</td>\n",
       "      <td>721</td>\n",
       "      <td>606</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>도농</td>\n",
       "      <td>9067</td>\n",
       "      <td>8349</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "0  20210201  중앙선   용문    1282    1259  20210204\n",
       "1  20210201  중앙선   지평      48      43  20210204\n",
       "2  20210201  중앙선   아신     415     413  20210204\n",
       "3  20210201  중앙선   양수    1463    1466  20210204\n",
       "4  20210201  중앙선  운길산     495     463  20210204\n",
       "5  20210201  중앙선   팔당     687     662  20210204\n",
       "6  20210201  중앙선   도심    2237    1736  20210204\n",
       "7  20210201  중앙선   덕소    5139    5082  20210204\n",
       "8  20210201  중앙선   양정     721     606  20210204\n",
       "9  20210201  중앙선   도농    9067    8349  20210204"
      ]
     },
     "execution_count": 61,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 인덱싱 사용하여 로우 선택\n",
    "df[0:10]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 62,
   "id": "c7303958-4ea3-4a6f-aa0a-73cd7c8e8662",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
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       "    .dataframe tbody tr th:only-of-type {\n",
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       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>사용일자</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "          노선명  역명  승차총승객수  하차총승객수      등록일자\n",
       "사용일자                                       \n",
       "20210201  중앙선  용문    1282    1259  20210204\n",
       "20210201  중앙선  지평      48      43  20210204\n",
       "20210201  중앙선  아신     415     413  20210204"
      ]
     },
     "execution_count": 62,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 인덱스를 ‘사용일자’로 바꾸어 설정\n",
    "df2 = df.set_index('사용일자')\n",
    "df2.head(3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 63,
   "id": "d0000922-197d-495e-8ade-8f8a9fe0f0a2",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "노선명            중앙선\n",
       "역명              지평\n",
       "승차총승객수          48\n",
       "하차총승객수          43\n",
       "등록일자      20210204\n",
       "Name: 20210201, dtype: object"
      ]
     },
     "execution_count": 63,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# iloc[] 인덱스에 해당하는 컬럼에 있는 값으로 선택\n",
    "df2.iloc[1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 68,
   "id": "e39e327e-24f2-471e-9ed6-05577fb22c8a",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>경원선</td>\n",
       "      <td>도봉</td>\n",
       "      <td>5561</td>\n",
       "      <td>5396</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>1호선</td>\n",
       "      <td>서울역</td>\n",
       "      <td>35821</td>\n",
       "      <td>33113</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>신원</td>\n",
       "      <td>166</td>\n",
       "      <td>134</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>8호선</td>\n",
       "      <td>산성</td>\n",
       "      <td>6122</td>\n",
       "      <td>6090</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20210201</th>\n",
       "      <td>중앙선</td>\n",
       "      <td>원덕</td>\n",
       "      <td>273</td>\n",
       "      <td>249</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>599 rows × 5 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "          노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "사용일자                                        \n",
       "20210201  중앙선   용문    1282    1259  20210204\n",
       "20210201  중앙선   지평      48      43  20210204\n",
       "20210201  중앙선   아신     415     413  20210204\n",
       "20210201  중앙선   양수    1463    1466  20210204\n",
       "20210201  중앙선  운길산     495     463  20210204\n",
       "...       ...  ...     ...     ...       ...\n",
       "20210201  경원선   도봉    5561    5396  20210204\n",
       "20210201  1호선  서울역   35821   33113  20210204\n",
       "20210201  중앙선   신원     166     134  20210204\n",
       "20210201  8호선   산성    6122    6090  20210204\n",
       "20210201  중앙선   원덕     273     249  20210204\n",
       "\n",
       "[599 rows x 5 columns]"
      ]
     },
     "execution_count": 68,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 로우 값로 선택\n",
    "df2.loc[20210201]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 69,
   "id": "acc4d5b7-283c-448c-a941-969b3e865e22",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0        False\n",
       "1        False\n",
       "2        False\n",
       "3        False\n",
       "4        False\n",
       "         ...  \n",
       "16746    False\n",
       "16747    False\n",
       "16748    False\n",
       "16749    False\n",
       "16750    False\n",
       "Name: 노선명, Length: 16751, dtype: bool"
      ]
     },
     "execution_count": 69,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 조건에 맞는 컬럼명 선택\n",
    "df['노선명'] == '2호선'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 70,
   "id": "84ac1b2f-4cdf-4694-b3b0-663da8ffdb2b",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>532</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>용두(동대문구청)</td>\n",
       "      <td>2365</td>\n",
       "      <td>2430</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>533</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>신정네거리</td>\n",
       "      <td>9269</td>\n",
       "      <td>9599</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>534</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>양천구청</td>\n",
       "      <td>6318</td>\n",
       "      <td>6738</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>535</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>도림천</td>\n",
       "      <td>1434</td>\n",
       "      <td>1469</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>536</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>신설동</td>\n",
       "      <td>3046</td>\n",
       "      <td>3110</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16207</th>\n",
       "      <td>20210228</td>\n",
       "      <td>2호선</td>\n",
       "      <td>신설동</td>\n",
       "      <td>2806</td>\n",
       "      <td>2830</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16208</th>\n",
       "      <td>20210228</td>\n",
       "      <td>2호선</td>\n",
       "      <td>도림천</td>\n",
       "      <td>480</td>\n",
       "      <td>477</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16209</th>\n",
       "      <td>20210228</td>\n",
       "      <td>2호선</td>\n",
       "      <td>양천구청</td>\n",
       "      <td>3234</td>\n",
       "      <td>3281</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16210</th>\n",
       "      <td>20210228</td>\n",
       "      <td>2호선</td>\n",
       "      <td>신정네거리</td>\n",
       "      <td>4814</td>\n",
       "      <td>4805</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16211</th>\n",
       "      <td>20210228</td>\n",
       "      <td>2호선</td>\n",
       "      <td>용두(동대문구청)</td>\n",
       "      <td>1069</td>\n",
       "      <td>1029</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>1400 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명         역명  승차총승객수  하차총승객수      등록일자\n",
       "532    20210201  2호선  용두(동대문구청)    2365    2430  20210204\n",
       "533    20210201  2호선      신정네거리    9269    9599  20210204\n",
       "534    20210201  2호선       양천구청    6318    6738  20210204\n",
       "535    20210201  2호선        도림천    1434    1469  20210204\n",
       "536    20210201  2호선        신설동    3046    3110  20210204\n",
       "...         ...  ...        ...     ...     ...       ...\n",
       "16207  20210228  2호선        신설동    2806    2830  20210303\n",
       "16208  20210228  2호선        도림천     480     477  20210303\n",
       "16209  20210228  2호선       양천구청    3234    3281  20210303\n",
       "16210  20210228  2호선      신정네거리    4814    4805  20210303\n",
       "16211  20210228  2호선  용두(동대문구청)    1069    1029  20210303\n",
       "\n",
       "[1400 rows x 6 columns]"
      ]
     },
     "execution_count": 70,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 조건에 맞는 로우로만 구성해서 출력\n",
    "# 2중 쿼리라고 생각하면 될듯\n",
    "df[df['노선명'] == '2호선']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 71,
   "id": "9b61de52-f5db-4d38-b019-45b6af482de4",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>550</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>구로디지털단지</td>\n",
       "      <td>57932</td>\n",
       "      <td>58583</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>552</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>신림</td>\n",
       "      <td>57124</td>\n",
       "      <td>56022</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>560</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>77926</td>\n",
       "      <td>76056</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>562</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>선릉</td>\n",
       "      <td>53457</td>\n",
       "      <td>46468</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>566</th>\n",
       "      <td>20210201</td>\n",
       "      <td>2호선</td>\n",
       "      <td>잠실(송파구청)</td>\n",
       "      <td>56357</td>\n",
       "      <td>56358</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14994</th>\n",
       "      <td>20210226</td>\n",
       "      <td>2호선</td>\n",
       "      <td>구로디지털단지</td>\n",
       "      <td>61720</td>\n",
       "      <td>61649</td>\n",
       "      <td>20210301</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15001</th>\n",
       "      <td>20210226</td>\n",
       "      <td>2호선</td>\n",
       "      <td>홍대입구</td>\n",
       "      <td>54628</td>\n",
       "      <td>58375</td>\n",
       "      <td>20210301</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15579</th>\n",
       "      <td>20210227</td>\n",
       "      <td>2호선</td>\n",
       "      <td>잠실(송파구청)</td>\n",
       "      <td>56574</td>\n",
       "      <td>53383</td>\n",
       "      <td>20210302</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15585</th>\n",
       "      <td>20210227</td>\n",
       "      <td>2호선</td>\n",
       "      <td>강남</td>\n",
       "      <td>57464</td>\n",
       "      <td>57150</td>\n",
       "      <td>20210302</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15602</th>\n",
       "      <td>20210227</td>\n",
       "      <td>2호선</td>\n",
       "      <td>홍대입구</td>\n",
       "      <td>56129</td>\n",
       "      <td>60023</td>\n",
       "      <td>20210302</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>109 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명        역명  승차총승객수  하차총승객수      등록일자\n",
       "550    20210201  2호선   구로디지털단지   57932   58583  20210204\n",
       "552    20210201  2호선        신림   57124   56022  20210204\n",
       "560    20210201  2호선        강남   77926   76056  20210204\n",
       "562    20210201  2호선        선릉   53457   46468  20210204\n",
       "566    20210201  2호선  잠실(송파구청)   56357   56358  20210204\n",
       "...         ...  ...       ...     ...     ...       ...\n",
       "14994  20210226  2호선   구로디지털단지   61720   61649  20210301\n",
       "15001  20210226  2호선      홍대입구   54628   58375  20210301\n",
       "15579  20210227  2호선  잠실(송파구청)   56574   53383  20210302\n",
       "15585  20210227  2호선        강남   57464   57150  20210302\n",
       "15602  20210227  2호선      홍대입구   56129   60023  20210302\n",
       "\n",
       "[109 rows x 6 columns]"
      ]
     },
     "execution_count": 71,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 승차총승객수 50000 이상인 로우만 출력\n",
    "df[df['승차총승객수'] >= 50000]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 72,
   "id": "0c92e9d4-17d4-4f2c-a7b0-e5345d8a43d1",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array(['구로디지털단지', '신림', '강남', '선릉', '잠실(송파구청)', '역삼', '홍대입구', '삼성(무역센터)'],\n",
       "      dtype=object)"
      ]
     },
     "execution_count": 72,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df[df['승차총승객수'] > 50000]['역명'].unique() "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 73,
   "id": "47d63248-3b0d-47eb-b7db-eeeb67eedd21",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "88904"
      ]
     },
     "execution_count": 73,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2['승차총승객수'].max()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 74,
   "id": "e312dabe-00c3-4eda-981f-7aef38e007bd",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "20210226"
      ]
     },
     "execution_count": 74,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2['승차총승객수'].idxmax()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 75,
   "id": "e729d90d-1129-42de-a646-30548b8bef4c",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "14984"
      ]
     },
     "execution_count": 75,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2['승차총승객수'].argmax()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "28187dfa-3456-4748-bd6d-3764cf006321",
   "metadata": {},
   "source": [
    "## 삭제"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 76,
   "id": "d0160d7d-4390-4812-a8e6-962309346ee1",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>팔당</td>\n",
       "      <td>687</td>\n",
       "      <td>662</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16746</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>오빈</td>\n",
       "      <td>216</td>\n",
       "      <td>236</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16747</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양평</td>\n",
       "      <td>3299</td>\n",
       "      <td>3187</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16748</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>원덕</td>\n",
       "      <td>322</td>\n",
       "      <td>304</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16749</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1899</td>\n",
       "      <td>1716</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16750</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>30</td>\n",
       "      <td>31</td>\n",
       "      <td>20210303</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>16750 rows × 6 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "1      20210201  중앙선   지평      48      43  20210204\n",
       "2      20210201  중앙선   아신     415     413  20210204\n",
       "3      20210201  중앙선   양수    1463    1466  20210204\n",
       "4      20210201  중앙선  운길산     495     463  20210204\n",
       "5      20210201  중앙선   팔당     687     662  20210204\n",
       "...         ...  ...  ...     ...     ...       ...\n",
       "16746  20210228  중앙선   오빈     216     236  20210303\n",
       "16747  20210228  중앙선   양평    3299    3187  20210303\n",
       "16748  20210228  중앙선   원덕     322     304  20210303\n",
       "16749  20210228  중앙선   용문    1899    1716  20210303\n",
       "16750  20210228  중앙선   지평      30      31  20210303\n",
       "\n",
       "[16750 rows x 6 columns]"
      ]
     },
     "execution_count": 76,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 0번 인덱스 삭제\n",
    "df.drop(0)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 77,
   "id": "b2c0e5f9-33e4-46f6-bb91-9d01c20c1b20",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
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       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
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       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
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       "      <td>415</td>\n",
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       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
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       "      <td>495</td>\n",
       "      <td>463</td>\n",
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       "    <tr>\n",
       "      <th>...</th>\n",
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       "    </tr>\n",
       "    <tr>\n",
       "      <th>16746</th>\n",
       "      <td>20210228</td>\n",
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       "      <td>216</td>\n",
       "      <td>236</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16747</th>\n",
       "      <td>20210228</td>\n",
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       "      <td>3299</td>\n",
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       "    <tr>\n",
       "      <th>16748</th>\n",
       "      <td>20210228</td>\n",
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       "    <tr>\n",
       "      <th>16749</th>\n",
       "      <td>20210228</td>\n",
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       "      <td>용문</td>\n",
       "      <td>1899</td>\n",
       "      <td>1716</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16750</th>\n",
       "      <td>20210228</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>30</td>\n",
       "      <td>31</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>16751 rows × 5 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명   역명  승차총승객수  하차총승객수\n",
       "0      20210201  중앙선   용문    1282    1259\n",
       "1      20210201  중앙선   지평      48      43\n",
       "2      20210201  중앙선   아신     415     413\n",
       "3      20210201  중앙선   양수    1463    1466\n",
       "4      20210201  중앙선  운길산     495     463\n",
       "...         ...  ...  ...     ...     ...\n",
       "16746  20210228  중앙선   오빈     216     236\n",
       "16747  20210228  중앙선   양평    3299    3187\n",
       "16748  20210228  중앙선   원덕     322     304\n",
       "16749  20210228  중앙선   용문    1899    1716\n",
       "16750  20210228  중앙선   지평      30      31\n",
       "\n",
       "[16751 rows x 5 columns]"
      ]
     },
     "execution_count": 77,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 해당 컬럼 삭제\n",
    "df.drop(['등록일자'], axis=1)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "9011a748-767a-444e-b442-193bbaa82303",
   "metadata": {},
   "source": [
    "## 연산 - 산술연산"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 82,
   "id": "99e23870-ac1e-445e-b7ac-e83f0c1dfeae",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "      <td>20210201</td>\n",
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       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
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       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
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       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
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       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
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      ],
      "text/plain": [
       "       사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자\n",
       "0  20210201  중앙선   용문    1282    1259  20210204\n",
       "1  20210201  중앙선   지평      48      43  20210204\n",
       "2  20210201  중앙선   아신     415     413  20210204\n",
       "3  20210201  중앙선   양수    1463    1466  20210204\n",
       "4  20210201  중앙선  운길산     495     463  20210204"
      ]
     },
     "execution_count": 82,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 해당 컬럼의 모든 값을 2씩 증가시키기\n",
    "df['승차총승객수'] + 2\n",
    "df.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 84,
   "id": "0ba5ceaa-202c-4887-9ec6-dd2c3edae26b",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "      <th>2</th>\n",
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       "      <td>415</td>\n",
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       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
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       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "      <td>-3</td>\n",
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       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
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       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "      <td>32</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자  승하차총승객수차이\n",
       "0  20210201  중앙선   용문    1282    1259  20210204         23\n",
       "1  20210201  중앙선   지평      48      43  20210204          5\n",
       "2  20210201  중앙선   아신     415     413  20210204          2\n",
       "3  20210201  중앙선   양수    1463    1466  20210204         -3\n",
       "4  20210201  중앙선  운길산     495     463  20210204         32"
      ]
     },
     "execution_count": 84,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 컬럼 간 차이 계산한 값을 저장하여\n",
    "# 새로운 컬럼 생성\n",
    "df['승하차총승객수차이'] = df['승차총승객수'] - df['하차총승객수']\n",
    "df.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 85,
   "id": "33f85494-d1fc-4bc6-96e3-474c9d8ef859",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "30.870276401408873"
      ]
     },
     "execution_count": 85,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 평균 계산하기\n",
    "df['승하차총승객수차이'].mean()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "6c832245-f742-423e-a3b5-8435ba660268",
   "metadata": {},
   "source": [
    "## 연산 - 샘플링"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 140,
   "id": "c7f31b2b-090f-4976-9a60-b1d1b28c10a2",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>2802</th>\n",
       "      <td>20210205</td>\n",
       "      <td>7호선</td>\n",
       "      <td>먹골</td>\n",
       "      <td>9573</td>\n",
       "      <td>9532</td>\n",
       "      <td>20210208</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2059</th>\n",
       "      <td>20210204</td>\n",
       "      <td>5호선</td>\n",
       "      <td>올림픽공원(한국체대)</td>\n",
       "      <td>4017</td>\n",
       "      <td>3519</td>\n",
       "      <td>20210207</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12061</th>\n",
       "      <td>20210221</td>\n",
       "      <td>분당선</td>\n",
       "      <td>선정릉</td>\n",
       "      <td>1917</td>\n",
       "      <td>2012</td>\n",
       "      <td>20210224</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7434</th>\n",
       "      <td>20210213</td>\n",
       "      <td>7호선</td>\n",
       "      <td>뚝섬유원지</td>\n",
       "      <td>5315</td>\n",
       "      <td>4933</td>\n",
       "      <td>20210216</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2728</th>\n",
       "      <td>20210205</td>\n",
       "      <td>9호선</td>\n",
       "      <td>샛강</td>\n",
       "      <td>5695</td>\n",
       "      <td>5848</td>\n",
       "      <td>20210208</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9055</th>\n",
       "      <td>20210216</td>\n",
       "      <td>경춘선</td>\n",
       "      <td>강촌</td>\n",
       "      <td>278</td>\n",
       "      <td>237</td>\n",
       "      <td>20210219</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12343</th>\n",
       "      <td>20210221</td>\n",
       "      <td>7호선</td>\n",
       "      <td>도봉산</td>\n",
       "      <td>4859</td>\n",
       "      <td>7295</td>\n",
       "      <td>20210224</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10299</th>\n",
       "      <td>20210218</td>\n",
       "      <td>2호선</td>\n",
       "      <td>용두(동대문구청)</td>\n",
       "      <td>2169</td>\n",
       "      <td>2229</td>\n",
       "      <td>20210221</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12882</th>\n",
       "      <td>20210222</td>\n",
       "      <td>경부선</td>\n",
       "      <td>용산</td>\n",
       "      <td>28885</td>\n",
       "      <td>29448</td>\n",
       "      <td>20210225</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10992</th>\n",
       "      <td>20210219</td>\n",
       "      <td>6호선</td>\n",
       "      <td>연신내</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>20210222</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           사용일자  노선명           역명  승차총승객수  하차총승객수      등록일자\n",
       "2802   20210205  7호선           먹골    9573    9532  20210208\n",
       "2059   20210204  5호선  올림픽공원(한국체대)    4017    3519  20210207\n",
       "12061  20210221  분당선          선정릉    1917    2012  20210224\n",
       "7434   20210213  7호선        뚝섬유원지    5315    4933  20210216\n",
       "2728   20210205  9호선           샛강    5695    5848  20210208\n",
       "9055   20210216  경춘선           강촌     278     237  20210219\n",
       "12343  20210221  7호선          도봉산    4859    7295  20210224\n",
       "10299  20210218  2호선    용두(동대문구청)    2169    2229  20210221\n",
       "12882  20210222  경부선           용산   28885   29448  20210225\n",
       "10992  20210219  6호선          연신내       1       0  20210222"
      ]
     },
     "execution_count": 140,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#비복원추출\n",
    "sample_df = df.sample(n=10)\n",
    "sample_df"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "79dfb857-75e3-4d5b-860a-a4e6e3b7c4fd",
   "metadata": {},
   "source": [
    "## 연산 - 값 치환"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 141,
   "id": "78e5bef1-e945-4606-9e53-e8ae0112bd91",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "2802       7호선\n",
       "2059       5호선\n",
       "12061      분당선\n",
       "7434       7호선\n",
       "2728       9호선\n",
       "9055       경춘선\n",
       "12343      7호선\n",
       "10299    line2\n",
       "12882      경부선\n",
       "10992      6호선\n",
       "Name: 노선명, dtype: object"
      ]
     },
     "execution_count": 141,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "sample_df['노선명'].replace(['1호선', '2호선', '3호선', '4호선'], ['line1', 'line2', 'line3', 'line4'])"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "8a9dd541-4174-4fbd-8266-d1f79cd9495a",
   "metadata": {},
   "source": [
    "## 연산 - 함수 적용"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 90,
   "id": "23720e4f-d4de-4076-81d6-6be1b7941cac",
   "metadata": {},
   "outputs": [],
   "source": [
    "# 날짜 타입으로 형 변환\n",
    "def getDate(data):\n",
    "    data = str(data)\n",
    "    year = data[0:4]\n",
    "    month = data[4:6]\n",
    "    day = data[6:8]\n",
    "    return year+'-'+month+'-'+day"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 91,
   "id": "2cefda32-d89e-411e-9439-2f44a3d5448d",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'2021-02-01'"
      ]
     },
     "execution_count": 91,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "d = 20210201\n",
    "getDate(d)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 92,
   "id": "85a2ca8f-db8a-46a4-812a-93c018e275ef",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0        2021-02-01\n",
       "1        2021-02-01\n",
       "2        2021-02-01\n",
       "3        2021-02-01\n",
       "4        2021-02-01\n",
       "            ...    \n",
       "16746    2021-02-28\n",
       "16747    2021-02-28\n",
       "16748    2021-02-28\n",
       "16749    2021-02-28\n",
       "16750    2021-02-28\n",
       "Name: 사용일자, Length: 16751, dtype: object"
      ]
     },
     "execution_count": 92,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df['사용일자'].apply(getDate)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 93,
   "id": "fd8dec2d-0b57-4f1d-979d-32dc5ced8dc9",
   "metadata": {},
   "outputs": [],
   "source": [
    "df['사용일자1'] =  df['사용일자'].apply(getDate)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 94,
   "id": "8554af61-ad76-486a-9927-0b0b46fe98c4",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>노선명</th>\n",
       "      <th>역명</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "      <th>승하차총승객수차이</th>\n",
       "      <th>사용일자1</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>용문</td>\n",
       "      <td>1282</td>\n",
       "      <td>1259</td>\n",
       "      <td>20210204</td>\n",
       "      <td>23</td>\n",
       "      <td>2021-02-01</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>지평</td>\n",
       "      <td>48</td>\n",
       "      <td>43</td>\n",
       "      <td>20210204</td>\n",
       "      <td>5</td>\n",
       "      <td>2021-02-01</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>아신</td>\n",
       "      <td>415</td>\n",
       "      <td>413</td>\n",
       "      <td>20210204</td>\n",
       "      <td>2</td>\n",
       "      <td>2021-02-01</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>양수</td>\n",
       "      <td>1463</td>\n",
       "      <td>1466</td>\n",
       "      <td>20210204</td>\n",
       "      <td>-3</td>\n",
       "      <td>2021-02-01</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>20210201</td>\n",
       "      <td>중앙선</td>\n",
       "      <td>운길산</td>\n",
       "      <td>495</td>\n",
       "      <td>463</td>\n",
       "      <td>20210204</td>\n",
       "      <td>32</td>\n",
       "      <td>2021-02-01</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       사용일자  노선명   역명  승차총승객수  하차총승객수      등록일자  승하차총승객수차이       사용일자1\n",
       "0  20210201  중앙선   용문    1282    1259  20210204         23  2021-02-01\n",
       "1  20210201  중앙선   지평      48      43  20210204          5  2021-02-01\n",
       "2  20210201  중앙선   아신     415     413  20210204          2  2021-02-01\n",
       "3  20210201  중앙선   양수    1463    1466  20210204         -3  2021-02-01\n",
       "4  20210201  중앙선  운길산     495     463  20210204         32  2021-02-01"
      ]
     },
     "execution_count": 94,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 96,
   "id": "19d13ffa-9596-49c4-855f-468af9f38251",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0       2021-02-01\n",
       "1       2021-02-01\n",
       "2       2021-02-01\n",
       "3       2021-02-01\n",
       "4       2021-02-01\n",
       "           ...    \n",
       "16746   2021-02-28\n",
       "16747   2021-02-28\n",
       "16748   2021-02-28\n",
       "16749   2021-02-28\n",
       "16750   2021-02-28\n",
       "Name: 사용일자1, Length: 16751, dtype: datetime64[ns]"
      ]
     },
     "execution_count": 96,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# datetime64 형식으로 형변환 완료\n",
    "df['사용일자1'].astype('datetime64')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 97,
   "id": "13155f2a-c469-4962-b843-07263708a55d",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0        1284\n",
       "1          50\n",
       "2         417\n",
       "3        1465\n",
       "4         497\n",
       "         ... \n",
       "16746     218\n",
       "16747    3301\n",
       "16748     324\n",
       "16749    1901\n",
       "16750      32\n",
       "Name: 승차총승객수, Length: 16751, dtype: int64"
      ]
     },
     "execution_count": 97,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 람다식으로 변환하기\n",
    "df['승차총승객수'].apply(lambda x: x+2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 98,
   "id": "1520b50e-c0a5-440a-a978-567cd71facca",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0        1284\n",
       "1          50\n",
       "2         417\n",
       "3        1465\n",
       "4         497\n",
       "         ... \n",
       "16746     218\n",
       "16747    3301\n",
       "16748     324\n",
       "16749    1901\n",
       "16750      32\n",
       "Name: 승차총승객수, Length: 16751, dtype: int64"
      ]
     },
     "execution_count": 98,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "plus2 = lambda x: x+2\n",
    "df['승차총승객수'].apply(plus2)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "9813de0c-ab8c-418c-a614-b45b72c7a2f0",
   "metadata": {},
   "source": [
    "## 원핫인코딩\n",
    "컬럼 내 모든 요소에 대해서 행열을 생성한 다음,\n",
    "\n",
    "값이 있는 부분에만 1을 주고\n",
    "\n",
    "값이 없는 나머지 부분에는 0을 주는 방법으로\n",
    "\n",
    "연산 가능한 데이터화 하는 것"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 100,
   "id": "ab3fe281-a390-434d-a0de-5787b9059e38",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>노선_2호선</th>\n",
       "      <th>노선_7호선</th>\n",
       "      <th>노선_경부선</th>\n",
       "      <th>노선_경인선</th>\n",
       "      <th>노선_경춘선</th>\n",
       "      <th>노선_분당선</th>\n",
       "      <th>노선_중앙선</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>9072</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5889</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1181</th>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11482</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5422</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9474</th>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5352</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1832</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12328</th>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7968</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       노선_2호선  노선_7호선  노선_경부선  노선_경인선  노선_경춘선  노선_분당선  노선_중앙선\n",
       "9072        0       0       0       1       0       0       0\n",
       "5889        0       0       0       0       1       0       0\n",
       "1181        1       0       0       0       0       0       0\n",
       "11482       0       0       0       0       0       1       0\n",
       "5422        0       0       0       0       0       0       1\n",
       "9474        0       1       0       0       0       0       0\n",
       "5352        0       0       0       0       0       0       1\n",
       "1832        0       0       0       0       0       1       0\n",
       "12328       0       1       0       0       0       0       0\n",
       "7968        0       0       1       0       0       0       0"
      ]
     },
     "execution_count": 100,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 원핫인코딩 메서드 get_dummies()\n",
    "dummies = pd.get_dummies(sample_df['노선명'], prefix='노선')\n",
    "dummies"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "a09efa8b-d38b-4ea0-bf31-d21e7e5a007b",
   "metadata": {},
   "source": [
    "## 결측치 처리"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 101,
   "id": "45672ee3-9b70-410b-afad-e306c1d0c013",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>학번</th>\n",
       "      <th>국어성적</th>\n",
       "      <th>영어성적</th>\n",
       "      <th>수학성적</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>2000</td>\n",
       "      <td>85.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2001</td>\n",
       "      <td>95.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>2002</td>\n",
       "      <td>75.0</td>\n",
       "      <td>100.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>2003</td>\n",
       "      <td>70.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>2004</td>\n",
       "      <td>100.0</td>\n",
       "      <td>80.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>2005</td>\n",
       "      <td>NaN</td>\n",
       "      <td>85.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>2006</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>2007</td>\n",
       "      <td>85.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>2008</td>\n",
       "      <td>80.0</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>2009</td>\n",
       "      <td>85.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>70.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     학번   국어성적   영어성적  수학성적\n",
       "0  2000   85.0   95.0   NaN\n",
       "1  2001   95.0   70.0   NaN\n",
       "2  2002   75.0  100.0   NaN\n",
       "3  2003   70.0   85.0   NaN\n",
       "4  2004  100.0   80.0   NaN\n",
       "5  2005    NaN   85.0   NaN\n",
       "6  2006   95.0   95.0   NaN\n",
       "7  2007   85.0   95.0  95.0\n",
       "8  2008   80.0    NaN   NaN\n",
       "9  2009   85.0   70.0  70.0"
      ]
     },
     "execution_count": 101,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import numpy as np\n",
    "data = {'학번':range(2000,2010),\n",
    "    '국어성적': [85, 95, 75, 70, 100, np.nan, 95, 85, 80, 85],\n",
    "    '영어성적': [95, 70, 100, 85, 80, 85, 95, 95, np.nan, 70],\n",
    "    '수학성적': [np.nan, np.nan, np.nan, np.nan, np.nan, np.nan, np.nan, 95, np.nan, 70],   }\n",
    "df = pd.DataFrame(data)\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 102,
   "id": "b0eb1d6b-8847-4fdd-817d-c1e5ab9d82e8",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "      <td>True</td>\n",
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       "      <th>2</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
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       "      <td>True</td>\n",
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       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "      <td>True</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "      학번   국어성적   영어성적   수학성적\n",
       "0  False  False  False   True\n",
       "1  False  False  False   True\n",
       "2  False  False  False   True\n",
       "3  False  False  False   True\n",
       "4  False  False  False   True\n",
       "5  False   True  False   True\n",
       "6  False  False  False   True\n",
       "7  False  False  False  False\n",
       "8  False  False   True   True\n",
       "9  False  False  False  False"
      ]
     },
     "execution_count": 102,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 결측치 확인\n",
    "df.isna()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 103,
   "id": "3ef20ad9-938f-4b61-af3a-74de54e2cac3",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "학번      0\n",
       "국어성적    1\n",
       "영어성적    1\n",
       "수학성적    8\n",
       "dtype: int64"
      ]
     },
     "execution_count": 103,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 결측치 총합 확인\n",
    "df.isna().sum()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 104,
   "id": "a7a34e86-0ab0-403c-b273-4fd30940fe25",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "      <th>국어성적</th>\n",
       "      <th>영어성적</th>\n",
       "      <th>수학성적</th>\n",
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       "      <th>1</th>\n",
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       "      <th>2</th>\n",
       "      <td>2002</td>\n",
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       "      <td>0.0</td>\n",
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       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>2003</td>\n",
       "      <td>70.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>0.0</td>\n",
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       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>2004</td>\n",
       "      <td>100.0</td>\n",
       "      <td>80.0</td>\n",
       "      <td>0.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>2005</td>\n",
       "      <td>0.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>0.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>2006</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>0.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>2007</td>\n",
       "      <td>85.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>2008</td>\n",
       "      <td>80.0</td>\n",
       "      <td>0.0</td>\n",
       "      <td>0.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>2009</td>\n",
       "      <td>85.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>70.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     학번   국어성적   영어성적  수학성적\n",
       "0  2000   85.0   95.0   0.0\n",
       "1  2001   95.0   70.0   0.0\n",
       "2  2002   75.0  100.0   0.0\n",
       "3  2003   70.0   85.0   0.0\n",
       "4  2004  100.0   80.0   0.0\n",
       "5  2005    0.0   85.0   0.0\n",
       "6  2006   95.0   95.0   0.0\n",
       "7  2007   85.0   95.0  95.0\n",
       "8  2008   80.0    0.0   0.0\n",
       "9  2009   85.0   70.0  70.0"
      ]
     },
     "execution_count": 104,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 결측치에 값 채우기\n",
    "df.fillna(0)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 106,
   "id": "2b69f775-ee61-46cf-b776-95c38412741e",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "      <th>학번</th>\n",
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       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>2002</td>\n",
       "      <td>75.0</td>\n",
       "      <td>100.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>2003</td>\n",
       "      <td>70.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>2004</td>\n",
       "      <td>100.0</td>\n",
       "      <td>80.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>2005</td>\n",
       "      <td>50.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>2006</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>2007</td>\n",
       "      <td>85.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>2008</td>\n",
       "      <td>80.0</td>\n",
       "      <td>50.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>2009</td>\n",
       "      <td>85.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>70.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     학번   국어성적   영어성적  수학성적\n",
       "0  2000   85.0   95.0  50.0\n",
       "1  2001   95.0   70.0  50.0\n",
       "2  2002   75.0  100.0  50.0\n",
       "3  2003   70.0   85.0  50.0\n",
       "4  2004  100.0   80.0  50.0\n",
       "5  2005   50.0   85.0  50.0\n",
       "6  2006   95.0   95.0  50.0\n",
       "7  2007   85.0   95.0  95.0\n",
       "8  2008   80.0   50.0  50.0\n",
       "9  2009   85.0   70.0  70.0"
      ]
     },
     "execution_count": 106,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# inplace= 인자값을 안주면 , 출력값에만 반영함\n",
    "# inplace=True 를 주면 원본에 반영\n",
    "df.fillna(50, inplace=True)\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 108,
   "id": "149e8b13-2ddc-4d7b-895d-1867ab077b71",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>학번</th>\n",
       "      <th>국어성적</th>\n",
       "      <th>영어성적</th>\n",
       "      <th>수학성적</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>2000</td>\n",
       "      <td>85.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2001</td>\n",
       "      <td>95.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>2002</td>\n",
       "      <td>75.0</td>\n",
       "      <td>100.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>2003</td>\n",
       "      <td>70.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>2004</td>\n",
       "      <td>100.0</td>\n",
       "      <td>80.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>2005</td>\n",
       "      <td>50.0</td>\n",
       "      <td>85.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>2006</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>2007</td>\n",
       "      <td>85.0</td>\n",
       "      <td>95.0</td>\n",
       "      <td>95.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>2008</td>\n",
       "      <td>80.0</td>\n",
       "      <td>50.0</td>\n",
       "      <td>50.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>2009</td>\n",
       "      <td>85.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>70.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     학번   국어성적   영어성적  수학성적\n",
       "0  2000   85.0   95.0  50.0\n",
       "1  2001   95.0   70.0  50.0\n",
       "2  2002   75.0  100.0  50.0\n",
       "3  2003   70.0   85.0  50.0\n",
       "4  2004  100.0   80.0  50.0\n",
       "5  2005   50.0   85.0  50.0\n",
       "6  2006   95.0   95.0  50.0\n",
       "7  2007   85.0   95.0  95.0\n",
       "8  2008   80.0   50.0  50.0\n",
       "9  2009   85.0   70.0  70.0"
      ]
     },
     "execution_count": 108,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 결측치가 있는 필드 삭제\n",
    "df.dropna()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "71253e39-72d2-4d34-8077-1eb2e8cf2ec3",
   "metadata": {},
   "source": [
    "## 변형"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 109,
   "id": "b62f9d61-74b4-427d-9019-1ed1b7494f66",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>사용일자</th>\n",
       "      <th>승차총승객수</th>\n",
       "      <th>하차총승객수</th>\n",
       "      <th>등록일자</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>노선명</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>16711.396429</td>\n",
       "      <td>16224.032143</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>20258.510000</td>\n",
       "      <td>20406.605714</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>11563.884739</td>\n",
       "      <td>11542.535752</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>13839.026099</td>\n",
       "      <td>13953.564560</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8774.492588</td>\n",
       "      <td>8727.040431</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>6499.918173</td>\n",
       "      <td>6405.854424</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>10210.968487</td>\n",
       "      <td>10060.233193</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8356.453782</td>\n",
       "      <td>8425.422269</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8110.387143</td>\n",
       "      <td>8246.852857</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9호선2~3단계</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>5238.137363</td>\n",
       "      <td>5156.379121</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>경강선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>1970.116883</td>\n",
       "      <td>1908.357143</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>경부선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8366.500000</td>\n",
       "      <td>8366.444139</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>경원선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>5051.796590</td>\n",
       "      <td>4940.018270</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>경의선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>2962.963365</td>\n",
       "      <td>2910.443691</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>경인선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>10789.323214</td>\n",
       "      <td>10672.037500</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>경춘선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>1462.635338</td>\n",
       "      <td>1409.640977</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>공항철도 1호선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>5076.122449</td>\n",
       "      <td>4643.492347</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>과천선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8984.544643</td>\n",
       "      <td>8827.571429</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>분당선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>7849.137539</td>\n",
       "      <td>8079.867632</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>수인선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>2341.289683</td>\n",
       "      <td>2335.438492</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>안산선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>6966.684066</td>\n",
       "      <td>6926.851648</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>우이신설선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>2559.425824</td>\n",
       "      <td>2508.461538</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>일산선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>8072.929078</td>\n",
       "      <td>7861.592199</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>장항선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>1495.559524</td>\n",
       "      <td>1447.095238</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>중앙선</th>\n",
       "      <td>2.021021e+07</td>\n",
       "      <td>3235.462585</td>\n",
       "      <td>3173.188776</td>\n",
       "      <td>2.021023e+07</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                  사용일자        승차총승객수        하차총승객수          등록일자\n",
       "노선명                                                             \n",
       "1호선       2.021021e+07  16711.396429  16224.032143  2.021023e+07\n",
       "2호선       2.021021e+07  20258.510000  20406.605714  2.021023e+07\n",
       "3호선       2.021021e+07  11563.884739  11542.535752  2.021023e+07\n",
       "4호선       2.021021e+07  13839.026099  13953.564560  2.021023e+07\n",
       "5호선       2.021021e+07   8774.492588   8727.040431  2.021023e+07\n",
       "6호선       2.021021e+07   6499.918173   6405.854424  2.021023e+07\n",
       "7호선       2.021021e+07  10210.968487  10060.233193  2.021023e+07\n",
       "8호선       2.021021e+07   8356.453782   8425.422269  2.021023e+07\n",
       "9호선       2.021021e+07   8110.387143   8246.852857  2.021023e+07\n",
       "9호선2~3단계  2.021021e+07   5238.137363   5156.379121  2.021023e+07\n",
       "경강선       2.021021e+07   1970.116883   1908.357143  2.021023e+07\n",
       "경부선       2.021021e+07   8366.500000   8366.444139  2.021023e+07\n",
       "경원선       2.021021e+07   5051.796590   4940.018270  2.021023e+07\n",
       "경의선       2.021021e+07   2962.963365   2910.443691  2.021023e+07\n",
       "경인선       2.021021e+07  10789.323214  10672.037500  2.021023e+07\n",
       "경춘선       2.021021e+07   1462.635338   1409.640977  2.021023e+07\n",
       "공항철도 1호선  2.021021e+07   5076.122449   4643.492347  2.021023e+07\n",
       "과천선       2.021021e+07   8984.544643   8827.571429  2.021023e+07\n",
       "분당선       2.021021e+07   7849.137539   8079.867632  2.021023e+07\n",
       "수인선       2.021021e+07   2341.289683   2335.438492  2.021023e+07\n",
       "안산선       2.021021e+07   6966.684066   6926.851648  2.021023e+07\n",
       "우이신설선     2.021021e+07   2559.425824   2508.461538  2.021023e+07\n",
       "일산선       2.021021e+07   8072.929078   7861.592199  2.021023e+07\n",
       "장항선       2.021021e+07   1495.559524   1447.095238  2.021023e+07\n",
       "중앙선       2.021021e+07   3235.462585   3173.188776  2.021023e+07"
      ]
     },
     "execution_count": 109,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df = pd.read_csv('CARD_SUBWAY_MONTH_202102.txt', index_col = False)\n",
    "df.groupby(['노선명']).mean()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 110,
   "id": "951788ca-1e22-445f-a1f1-887d7c6a0cd1",
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>성별</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>남자</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>D</td>\n",
       "      <td>남자</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름  성별\n",
       "0  A  남자\n",
       "1  B  여자\n",
       "2  D  남자"
      ]
     },
     "execution_count": 110,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df1 = pd.DataFrame({'이름': ['A', 'B', 'D'],\n",
    "                    '성별':['남자', '여자', '남자']\n",
    "                   })\n",
    "df1"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 111,
   "id": "82bf5800-ffa4-45fc-8fc5-292e3479b945",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>키</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>180</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>160</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>C</td>\n",
       "      <td>150</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름    키\n",
       "0  A  180\n",
       "1  B  160\n",
       "2  C  150"
      ]
     },
     "execution_count": 111,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2 = pd.DataFrame({'이름': ['A', 'B', 'C'],\n",
    "                    '키':[180, 160, 150],\n",
    "                   })\n",
    "df2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 113,
   "id": "46377611-fa5d-4e62-8364-661404f57495",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>성별</th>\n",
       "      <th>키</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>남자</td>\n",
       "      <td>180</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "      <td>160</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름  성별    키\n",
       "0  A  남자  180\n",
       "1  B  여자  160"
      ]
     },
     "execution_count": 113,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 교집합 join\n",
    "pd.merge(df1, df2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 115,
   "id": "67c1b494-313d-4d0a-b0d3-171b8975c41d",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>성별</th>\n",
       "      <th>키</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>남자</td>\n",
       "      <td>180.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "      <td>160.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>D</td>\n",
       "      <td>남자</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름  성별      키\n",
       "0  A  남자  180.0\n",
       "1  B  여자  160.0\n",
       "2  D  남자    NaN"
      ]
     },
     "execution_count": 115,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# left 조인\n",
    "# 좌측 df의 값은 누락없이 모두 join\n",
    "pd.merge(df1, df2, how='left')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 116,
   "id": "3f12776f-f05c-48a8-98d7-e99c94b4131b",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>성별</th>\n",
       "      <th>키</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>남자</td>\n",
       "      <td>180</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "      <td>160</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>C</td>\n",
       "      <td>NaN</td>\n",
       "      <td>150</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름   성별    키\n",
       "0  A   남자  180\n",
       "1  B   여자  160\n",
       "2  C  NaN  150"
      ]
     },
     "execution_count": 116,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# right 조인\n",
    "# 우측 df 값은 누락 없이 모두 join\n",
    "pd.merge(df1, df2, how='right')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 119,
   "id": "0f8f33d8-42c9-425b-90e1-8ae281dd2c4a",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>성별</th>\n",
       "      <th>키</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>남자</td>\n",
       "      <td>180.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "      <td>160.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>D</td>\n",
       "      <td>남자</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>C</td>\n",
       "      <td>NaN</td>\n",
       "      <td>150.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름   성별      키\n",
       "0  A   남자  180.0\n",
       "1  B   여자  160.0\n",
       "2  D   남자    NaN\n",
       "3  C  NaN  150.0"
      ]
     },
     "execution_count": 119,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# outer 조인\n",
    "# 양측의 요소를 모두 누락 없이 반영하는 합집합\n",
    "pd.merge(df1, df2, how='outer')"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "076ecfac-2842-4248-a900-9a35dcf1eab7",
   "metadata": {},
   "source": [
    "### 연습문제"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 120,
   "id": "3f1a86c6-0a77-45f0-a0bc-30235986880b",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "    .dataframe tbody tr th:only-of-type {\n",
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       "\n",
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       "\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>키</th>\n",
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       "  <tbody>\n",
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       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>180</td>\n",
       "      <td>23</td>\n",
       "      <td>서울</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>160</td>\n",
       "      <td>46</td>\n",
       "      <td>부산</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>C</td>\n",
       "      <td>150</td>\n",
       "      <td>33</td>\n",
       "      <td>대전</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>D</td>\n",
       "      <td>170</td>\n",
       "      <td>65</td>\n",
       "      <td>원주</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>E</td>\n",
       "      <td>170</td>\n",
       "      <td>28</td>\n",
       "      <td>제주</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름    키  나이  주소\n",
       "0  A  180  23  서울\n",
       "1  B  160  46  부산\n",
       "2  C  150  33  대전\n",
       "3  D  170  65  원주\n",
       "4  E  170  28  제주"
      ]
     },
     "execution_count": 120,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df1 = pd.DataFrame({'이름': ['A', 'B', 'C', 'D', 'E'],\n",
    "                    '키':[180, 160, 150, 170, 170],\n",
    "                    '나이': [23, 46, 33, 65, 28],\n",
    "                    '주소': ['서울', '부산', '대전', '원주', '제주']\n",
    "                   })\n",
    "df1"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 121,
   "id": "c54ff775-7dfb-4465-bcfe-d182973ed2b1",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "    .dataframe tbody tr th:only-of-type {\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
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       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>F</td>\n",
       "      <td>190</td>\n",
       "      <td>22</td>\n",
       "      <td>전주</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>G</td>\n",
       "      <td>180</td>\n",
       "      <td>18</td>\n",
       "      <td>서울</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>H</td>\n",
       "      <td>150</td>\n",
       "      <td>87</td>\n",
       "      <td>수원</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>I</td>\n",
       "      <td>160</td>\n",
       "      <td>45</td>\n",
       "      <td>부산</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>J</td>\n",
       "      <td>170</td>\n",
       "      <td>74</td>\n",
       "      <td>인천</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름    키  나이  주소\n",
       "0  F  190  22  전주\n",
       "1  G  180  18  서울\n",
       "2  H  150  87  수원\n",
       "3  I  160  45  부산\n",
       "4  J  170  74  인천"
      ]
     },
     "execution_count": 121,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2 = pd.DataFrame({'이름': ['F', 'G', 'H', 'I', 'J'],\n",
    "                    '키':[190, 180, 150, 160, 170],\n",
    "                    '나이': [22, 18, 87, 45, 74],\n",
    "                    '주소': ['전주', '서울', '수원', '부산', '인천']\n",
    "                   })\n",
    "df2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 127,
   "id": "279f23ac-32e6-449e-bbb8-709c2630ab3b",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "<style scoped>\n",
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       "\n",
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       "      <th>주소</th>\n",
       "    </tr>\n",
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       "  <tbody>\n",
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       "      <td>180</td>\n",
       "      <td>23</td>\n",
       "      <td>서울</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>160</td>\n",
       "      <td>46</td>\n",
       "      <td>부산</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>C</td>\n",
       "      <td>150</td>\n",
       "      <td>33</td>\n",
       "      <td>대전</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>D</td>\n",
       "      <td>170</td>\n",
       "      <td>65</td>\n",
       "      <td>원주</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>E</td>\n",
       "      <td>170</td>\n",
       "      <td>28</td>\n",
       "      <td>제주</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>F</td>\n",
       "      <td>190</td>\n",
       "      <td>22</td>\n",
       "      <td>전주</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>G</td>\n",
       "      <td>180</td>\n",
       "      <td>18</td>\n",
       "      <td>서울</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>H</td>\n",
       "      <td>150</td>\n",
       "      <td>87</td>\n",
       "      <td>수원</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>I</td>\n",
       "      <td>160</td>\n",
       "      <td>45</td>\n",
       "      <td>부산</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>J</td>\n",
       "      <td>170</td>\n",
       "      <td>74</td>\n",
       "      <td>인천</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름    키  나이  주소\n",
       "0  A  180  23  서울\n",
       "1  B  160  46  부산\n",
       "2  C  150  33  대전\n",
       "3  D  170  65  원주\n",
       "4  E  170  28  제주\n",
       "0  F  190  22  전주\n",
       "1  G  180  18  서울\n",
       "2  H  150  87  수원\n",
       "3  I  160  45  부산\n",
       "4  J  170  74  인천"
      ]
     },
     "execution_count": 127,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 컬럼명이 모두 동일한 데이터 형태인 경우\n",
    "# 특정 기준값을 기준으로 합치는 것보다는\n",
    "# 로우나 컬럼을 이어서 붙이는 형태로 합치는 것이 좋음\n",
    "# 이어붙일 때 사용하는 메서드 concat()\n",
    "# axis값을 안주면 기본적으로 row를 따라 이어붙인 데이터프레임 반환\n",
    "pd.concat([df1, df2])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 128,
   "id": "333cbbb5-e932-4001-95f5-c12936bb9a36",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>키</th>\n",
       "      <th>나이</th>\n",
       "      <th>주소</th>\n",
       "      <th>이름</th>\n",
       "      <th>키</th>\n",
       "      <th>나이</th>\n",
       "      <th>주소</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>180</td>\n",
       "      <td>23</td>\n",
       "      <td>서울</td>\n",
       "      <td>F</td>\n",
       "      <td>190</td>\n",
       "      <td>22</td>\n",
       "      <td>전주</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>160</td>\n",
       "      <td>46</td>\n",
       "      <td>부산</td>\n",
       "      <td>G</td>\n",
       "      <td>180</td>\n",
       "      <td>18</td>\n",
       "      <td>서울</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>C</td>\n",
       "      <td>150</td>\n",
       "      <td>33</td>\n",
       "      <td>대전</td>\n",
       "      <td>H</td>\n",
       "      <td>150</td>\n",
       "      <td>87</td>\n",
       "      <td>수원</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>D</td>\n",
       "      <td>170</td>\n",
       "      <td>65</td>\n",
       "      <td>원주</td>\n",
       "      <td>I</td>\n",
       "      <td>160</td>\n",
       "      <td>45</td>\n",
       "      <td>부산</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>E</td>\n",
       "      <td>170</td>\n",
       "      <td>28</td>\n",
       "      <td>제주</td>\n",
       "      <td>J</td>\n",
       "      <td>170</td>\n",
       "      <td>74</td>\n",
       "      <td>인천</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름    키  나이  주소 이름    키  나이  주소\n",
       "0  A  180  23  서울  F  190  22  전주\n",
       "1  B  160  46  부산  G  180  18  서울\n",
       "2  C  150  33  대전  H  150  87  수원\n",
       "3  D  170  65  원주  I  160  45  부산\n",
       "4  E  170  28  제주  J  170  74  인천"
      ]
     },
     "execution_count": 128,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# axis=1 값을 주면 컬럼을 따라 이어붙인 데이터프레임 반환\n",
    "pd.concat([df1, df2], axis = 1)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "d4a36e8c-d655-45ae-a99f-a29bf32ddb5c",
   "metadata": {},
   "source": [
    "## 저장"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 129,
   "id": "963344f7-7406-4dc3-ab2b-bccd04947965",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>이름</th>\n",
       "      <th>성별</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>A</td>\n",
       "      <td>남자</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>D</td>\n",
       "      <td>남자</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  이름  성별\n",
       "0  A  남자\n",
       "1  B  여자\n",
       "2  D  남자"
      ]
     },
     "execution_count": 129,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df = pd.DataFrame({'이름': ['A', 'B', 'D'],\n",
    "                    '성별':['남자', '여자', '남자']\n",
    "                   })\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 130,
   "id": "538713ea-eab8-4a43-9cfe-3cd0d64dacf4",
   "metadata": {},
   "outputs": [],
   "source": [
    "df.to_csv('dataframe.csv', encoding='euc-kr')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 131,
   "id": "68e26d0b-32bc-4c12-9a53-082a0491857e",
   "metadata": {},
   "outputs": [],
   "source": [
    "df.to_csv('dataframe.csv', encoding='euc-kr', index = False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 132,
   "id": "1fa6e7af-808f-4109-a733-b5296e3c2a30",
   "metadata": {},
   "outputs": [],
   "source": [
    "df.to_csv('dataframe.csv', encoding='euc-kr', header= False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 133,
   "id": "b2a06a19-9512-4c99-a6a7-26112aabc4b3",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>0</th>\n",
       "      <th>A</th>\n",
       "      <th>남자</th>\n",
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       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
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       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2</td>\n",
       "      <td>D</td>\n",
       "      <td>남자</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   0  A  남자\n",
       "0  1  B  여자\n",
       "1  2  D  남자"
      ]
     },
     "execution_count": 133,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df1 = pd.read_csv('dataframe.csv', encoding='euc-kr')\n",
    "df1"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 134,
   "id": "abdc827b-b6aa-41de-a4e7-c30e9c74de55",
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
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       "\n",
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>A</th>\n",
       "      <th>남자</th>\n",
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       "      <th>0</th>\n",
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       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>B</td>\n",
       "      <td>여자</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>D</td>\n",
       "      <td>남자</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   A  남자\n",
       "0       \n",
       "1  B  여자\n",
       "2  D  남자"
      ]
     },
     "execution_count": 134,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df1 = pd.read_csv('dataframe.csv', encoding='euc-kr', index_col= 0)\n",
    "df1"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "5c8973c1-46eb-4f09-b1ee-3eda58b5b04a",
   "metadata": {},
   "outputs": [],
   "source": []
  }
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