Exercises3_3.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Regiment"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Introduction:\n",
    "\n",
    "Special thanks to: http://chrisalbon.com/ for sharing the dataset and materials.\n",
    "\n",
    "### Step 1. Import the necessary libraries"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [],
   "source": [
    "import pandas as pd"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 2. Create the DataFrame with the following values:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "raw_data = {'regiment': ['Nighthawks', 'Nighthawks', 'Nighthawks', 'Nighthawks', 'Dragoons', 'Dragoons', 'Dragoons', 'Dragoons', 'Scouts', 'Scouts', 'Scouts', 'Scouts'], \n",
    "        'company': ['1st', '1st', '2nd', '2nd', '1st', '1st', '2nd', '2nd','1st', '1st', '2nd', '2nd'], \n",
    "        'name': ['Miller', 'Jacobson', 'Ali', 'Milner', 'Cooze', 'Jacon', 'Ryaner', 'Sone', 'Sloan', 'Piger', 'Riani', 'Ali'], \n",
    "        'preTestScore': [4, 24, 31, 2, 3, 4, 24, 31, 2, 3, 2, 3],\n",
    "        'postTestScore': [25, 94, 57, 62, 70, 25, 94, 57, 62, 70, 62, 70]}"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 3. Assign it to a variable called regiment.\n",
    "#### Don't forget to name each column"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
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   "outputs": [
    {
     "data": {
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       "<div>\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>regiment</th>\n",
       "      <th>company</th>\n",
       "      <th>name</th>\n",
       "      <th>preTestScore</th>\n",
       "      <th>postTestScore</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>1st</td>\n",
       "      <td>Miller</td>\n",
       "      <td>4</td>\n",
       "      <td>25</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>1st</td>\n",
       "      <td>Jacobson</td>\n",
       "      <td>24</td>\n",
       "      <td>94</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Ali</td>\n",
       "      <td>31</td>\n",
       "      <td>57</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Milner</td>\n",
       "      <td>2</td>\n",
       "      <td>62</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>1st</td>\n",
       "      <td>Cooze</td>\n",
       "      <td>3</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>1st</td>\n",
       "      <td>Jacon</td>\n",
       "      <td>4</td>\n",
       "      <td>25</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Ryaner</td>\n",
       "      <td>24</td>\n",
       "      <td>94</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Sone</td>\n",
       "      <td>31</td>\n",
       "      <td>57</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>1st</td>\n",
       "      <td>Sloan</td>\n",
       "      <td>2</td>\n",
       "      <td>62</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>1st</td>\n",
       "      <td>Piger</td>\n",
       "      <td>3</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Riani</td>\n",
       "      <td>2</td>\n",
       "      <td>62</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Ali</td>\n",
       "      <td>3</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "      regiment company      name  preTestScore  postTestScore\n",
       "0   Nighthawks     1st    Miller             4             25\n",
       "1   Nighthawks     1st  Jacobson            24             94\n",
       "2   Nighthawks     2nd       Ali            31             57\n",
       "3   Nighthawks     2nd    Milner             2             62\n",
       "4     Dragoons     1st     Cooze             3             70\n",
       "5     Dragoons     1st     Jacon             4             25\n",
       "6     Dragoons     2nd    Ryaner            24             94\n",
       "7     Dragoons     2nd      Sone            31             57\n",
       "8       Scouts     1st     Sloan             2             62\n",
       "9       Scouts     1st     Piger             3             70\n",
       "10      Scouts     2nd     Riani             2             62\n",
       "11      Scouts     2nd       Ali             3             70"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment = pd.DataFrame(raw_data)\n",
    "regiment"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 4. What is the mean preTestScore from the regiment Nighthawks?  "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
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   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "15.25"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby('regiment')['preTestScore'].mean().loc['Nighthawks']"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 5. Present general statistics by company"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false,
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    {
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       "  <thead>\n",
       "    <tr>\n",
       "      <th></th>\n",
       "      <th colspan=\"8\" halign=\"left\">preTestScore</th>\n",
       "      <th colspan=\"8\" halign=\"left\">postTestScore</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th></th>\n",
       "      <th>count</th>\n",
       "      <th>mean</th>\n",
       "      <th>std</th>\n",
       "      <th>min</th>\n",
       "      <th>25%</th>\n",
       "      <th>50%</th>\n",
       "      <th>75%</th>\n",
       "      <th>max</th>\n",
       "      <th>count</th>\n",
       "      <th>mean</th>\n",
       "      <th>std</th>\n",
       "      <th>min</th>\n",
       "      <th>25%</th>\n",
       "      <th>50%</th>\n",
       "      <th>75%</th>\n",
       "      <th>max</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>company</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
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       "      <th></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>1st</th>\n",
       "      <td>6.0</td>\n",
       "      <td>6.666667</td>\n",
       "      <td>8.524475</td>\n",
       "      <td>2.0</td>\n",
       "      <td>3.00</td>\n",
       "      <td>3.5</td>\n",
       "      <td>4.00</td>\n",
       "      <td>24.0</td>\n",
       "      <td>6.0</td>\n",
       "      <td>57.666667</td>\n",
       "      <td>27.485754</td>\n",
       "      <td>25.0</td>\n",
       "      <td>34.25</td>\n",
       "      <td>66.0</td>\n",
       "      <td>70.0</td>\n",
       "      <td>94.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2nd</th>\n",
       "      <td>6.0</td>\n",
       "      <td>15.500000</td>\n",
       "      <td>14.652645</td>\n",
       "      <td>2.0</td>\n",
       "      <td>2.25</td>\n",
       "      <td>13.5</td>\n",
       "      <td>29.25</td>\n",
       "      <td>31.0</td>\n",
       "      <td>6.0</td>\n",
       "      <td>67.000000</td>\n",
       "      <td>14.057027</td>\n",
       "      <td>57.0</td>\n",
       "      <td>58.25</td>\n",
       "      <td>62.0</td>\n",
       "      <td>68.0</td>\n",
       "      <td>94.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "        preTestScore                                                      \\\n",
       "               count       mean        std  min   25%   50%    75%   max   \n",
       "company                                                                    \n",
       "1st              6.0   6.666667   8.524475  2.0  3.00   3.5   4.00  24.0   \n",
       "2nd              6.0  15.500000  14.652645  2.0  2.25  13.5  29.25  31.0   \n",
       "\n",
       "        postTestScore                                                       \n",
       "                count       mean        std   min    25%   50%   75%   max  \n",
       "company                                                                     \n",
       "1st               6.0  57.666667  27.485754  25.0  34.25  66.0  70.0  94.0  \n",
       "2nd               6.0  67.000000  14.057027  57.0  58.25  62.0  68.0  94.0  "
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby('company').describe()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 6. What is the mean of each company's preTestScore?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {
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   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "company\n",
       "1st     6.666667\n",
       "2nd    15.500000\n",
       "Name: preTestScore, dtype: float64"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby('company').mean().loc[:, 'preTestScore']"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 7. Present the mean preTestScores grouped by regiment and company"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "regiment    company\n",
       "Dragoons    1st         3.5\n",
       "            2nd        27.5\n",
       "Nighthawks  1st        14.0\n",
       "            2nd        16.5\n",
       "Scouts      1st         2.5\n",
       "            2nd         2.5\n",
       "Name: preTestScore, dtype: float64"
      ]
     },
     "execution_count": 23,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby(['regiment', 'company']).mean().loc[:, 'preTestScore']"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 8. Present the mean preTestScores grouped by regiment and company without heirarchical indexing"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {
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    "jupyter": {
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    }
   },
   "outputs": [
    {
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>company</th>\n",
       "      <th>preTestScore</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>regiment</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>Dragoons</th>\n",
       "      <td>1st</td>\n",
       "      <td>3.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Dragoons</th>\n",
       "      <td>2nd</td>\n",
       "      <td>27.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Nighthawks</th>\n",
       "      <td>1st</td>\n",
       "      <td>14.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Nighthawks</th>\n",
       "      <td>2nd</td>\n",
       "      <td>16.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Scouts</th>\n",
       "      <td>1st</td>\n",
       "      <td>2.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Scouts</th>\n",
       "      <td>2nd</td>\n",
       "      <td>2.5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           company  preTestScore\n",
       "regiment                        \n",
       "Dragoons       1st           3.5\n",
       "Dragoons       2nd          27.5\n",
       "Nighthawks     1st          14.0\n",
       "Nighthawks     2nd          16.5\n",
       "Scouts         1st           2.5\n",
       "Scouts         2nd           2.5"
      ]
     },
     "execution_count": 33,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby(['regiment', 'company']).mean().loc[:, 'preTestScore'].reset_index(level=1)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 9. Group the entire dataframe by regiment and company"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 55,
   "metadata": {
    "collapsed": false,
    "jupyter": {
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   },
   "outputs": [
    {
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>regiment</th>\n",
       "      <th>company</th>\n",
       "      <th>name</th>\n",
       "      <th>preTestScore</th>\n",
       "      <th>postTestScore</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>1st</td>\n",
       "      <td>Miller</td>\n",
       "      <td>4</td>\n",
       "      <td>25</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>1st</td>\n",
       "      <td>Jacobson</td>\n",
       "      <td>24</td>\n",
       "      <td>94</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Ali</td>\n",
       "      <td>31</td>\n",
       "      <td>57</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Milner</td>\n",
       "      <td>2</td>\n",
       "      <td>62</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>1st</td>\n",
       "      <td>Cooze</td>\n",
       "      <td>3</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>1st</td>\n",
       "      <td>Jacon</td>\n",
       "      <td>4</td>\n",
       "      <td>25</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Ryaner</td>\n",
       "      <td>24</td>\n",
       "      <td>94</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>Dragoons</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Sone</td>\n",
       "      <td>31</td>\n",
       "      <td>57</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>1st</td>\n",
       "      <td>Sloan</td>\n",
       "      <td>2</td>\n",
       "      <td>62</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>1st</td>\n",
       "      <td>Piger</td>\n",
       "      <td>3</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Riani</td>\n",
       "      <td>2</td>\n",
       "      <td>62</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>Scouts</td>\n",
       "      <td>2nd</td>\n",
       "      <td>Ali</td>\n",
       "      <td>3</td>\n",
       "      <td>70</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "      regiment company      name  preTestScore  postTestScore\n",
       "0   Nighthawks     1st    Miller             4             25\n",
       "1   Nighthawks     1st  Jacobson            24             94\n",
       "2   Nighthawks     2nd       Ali            31             57\n",
       "3   Nighthawks     2nd    Milner             2             62\n",
       "4     Dragoons     1st     Cooze             3             70\n",
       "5     Dragoons     1st     Jacon             4             25\n",
       "6     Dragoons     2nd    Ryaner            24             94\n",
       "7     Dragoons     2nd      Sone            31             57\n",
       "8       Scouts     1st     Sloan             2             62\n",
       "9       Scouts     1st     Piger             3             70\n",
       "10      Scouts     2nd     Riani             2             62\n",
       "11      Scouts     2nd       Ali             3             70"
      ]
     },
     "execution_count": 55,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby(['regiment', 'company']).head()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 10. What is the number of observations in each regiment and company"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 51,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
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   "outputs": [
    {
     "data": {
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>preTestScore</th>\n",
       "      <th>postTestScore</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>regiment</th>\n",
       "      <th>company</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
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       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th rowspan=\"2\" valign=\"top\">Dragoons</th>\n",
       "      <th>1st</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2nd</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th rowspan=\"2\" valign=\"top\">Nighthawks</th>\n",
       "      <th>1st</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2nd</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th rowspan=\"2\" valign=\"top\">Scouts</th>\n",
       "      <th>1st</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2nd</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                    name  preTestScore  postTestScore\n",
       "regiment   company                                   \n",
       "Dragoons   1st         2             2              2\n",
       "           2nd         2             2              2\n",
       "Nighthawks 1st         2             2              2\n",
       "           2nd         2             2              2\n",
       "Scouts     1st         2             2              2\n",
       "           2nd         2             2              2"
      ]
     },
     "execution_count": 51,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.groupby(['regiment', 'company']).count()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Step 11. Iterate over a group and print the name and the whole data from the regiment"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 58,
   "metadata": {
    "collapsed": false,
    "jupyter": {
     "outputs_hidden": false
    }
   },
   "outputs": [
    {
     "data": {
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>regiment</th>\n",
       "      <th>company</th>\n",
       "      <th>name</th>\n",
       "      <th>preTestScore</th>\n",
       "      <th>postTestScore</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>1st</td>\n",
       "      <td>Miller</td>\n",
       "      <td>4</td>\n",
       "      <td>25</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Nighthawks</td>\n",
       "      <td>1st</td>\n",
       "      <td>Jacobson</td>\n",
       "      <td>24</td>\n",
       "      <td>94</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     regiment company      name  preTestScore  postTestScore\n",
       "0  Nighthawks     1st    Miller             4             25\n",
       "1  Nighthawks     1st  Jacobson            24             94"
      ]
     },
     "execution_count": 58,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "regiment.loc[0:1, :]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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