15 - Functions Basics - Part 3.ipynb

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   "source": [
    "# Function Arguments\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello satish , Good Morning\n"
     ]
    }
   ],
   "source": [
    "def greet(name, msg):\n",
    "    \"\"\"\n",
    "    This function greets to person with the provided message\n",
    "    \"\"\"\n",
    "    print(\"Hello {0} , {1}\".format(name, msg))\n",
    "\n",
    "#call the function with arguments\n",
    "greet(\"satish\", \"Good Morning\")\n"
   ]
  },
  {
   "cell_type": "code",
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   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "greet() missing 1 required positional argument: 'msg'",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-3-b48ea98044bf>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;31m#suppose if we pass one argument\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      2\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 3\u001b[0;31m \u001b[0mgreet\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"satish\"\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;31m#will get an error\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mTypeError\u001b[0m: greet() missing 1 required positional argument: 'msg'"
     ]
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   ],
   "source": [
    "#suppose if we pass one argument\n",
    "\n",
    "greet(\"satish\") #will get an error\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Different Forms of Arguments"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 1. Default Arguments"
   ]
  },
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   "cell_type": "markdown",
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   "source": [
    "We can provide a default value to an argument by using the assignment operator (=). "
   ]
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   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello satish , Good Night\n"
     ]
    }
   ],
   "source": [
    "def greet(name, msg=\"Good Morning\"):\n",
    "    \"\"\"\n",
    "    This function greets to person with the provided message\n",
    "    if message is not provided, it defaults to \"Good Morning\"\n",
    "    \"\"\"\n",
    "    print(\"Hello {0} , {1}\".format(name, msg))\n",
    "\n",
    "greet(\"satish\", \"Good Night\")\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello satish , Good Morning\n"
     ]
    }
   ],
   "source": [
    "#with out msg argument\n",
    "greet(\"satish\")\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Once we have a default argument, all the arguments to its right must also have default values."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "def greet(msg=\"Good Morning\", name)   \n",
    "\n",
    "#will get a SyntaxError : non-default argument follows default argument"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 2. Keyword Arguments"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "kwargs allows you to pass keyworded variable length of arguments to a function. You should use **kwargs if you want to handle named arguments in a function"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello satish , Good Morning\n"
     ]
    }
   ],
   "source": [
    "def greet(**kwargs):\n",
    "    \"\"\"\n",
    "    This function greets to person with the provided message\n",
    "    \"\"\"\n",
    "    if kwargs:\n",
    "        print(\"Hello {0} , {1}\".format(kwargs['name'], kwargs['msg']))\n",
    "greet(name=\"satish\", msg=\"Good Morning\")\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 3. Arbitary Arguments"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Sometimes, we do not know in advance the number of arguments that will be passed into a function.Python allows us to handle this kind of situation through function calls with arbitrary number of arguments."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "('satish', 'murali', 'naveen', 'srikanth')\n",
      "Hello,  satish \n",
      "Hello,  murali \n",
      "Hello,  naveen \n",
      "Hello,  srikanth \n"
     ]
    }
   ],
   "source": [
    "def greet(*names):\n",
    "    \"\"\"\n",
    "    This function greets all persons in the names tuple \n",
    "    \"\"\"\n",
    "    print(names)\n",
    "    \n",
    "    for name in names:\n",
    "        print(\"Hello,  {0} \".format(name))\n",
    "\n",
    "greet(\"satish\", \"murali\", \"naveen\", \"srikanth\")\n"
   ]
  },
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   "execution_count": null,
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