positional_or_keyword.ipynb

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   "cell_type": "markdown",
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   "source": [
    "__In the below function definition, a & b are positional parameters and c is the keyword parameter with a default value of 30.__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "def func(a, b, c=30):\n",
    "    print(f\"a:{a}, b:{b}, c:{c}\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "__In the function call `func(10, 20)`, arguments `10` and `20` are mapped to `a` & `b` by position. Since `c` isn't passed as an argument, it gets the default value i.e. `30`.__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "a:10, b:20, c:30\n"
     ]
    }
   ],
   "source": [
    "func(10, 20)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "__Similarly, `func(20, 10)` works the same as above but the values of `a` & `b` are interchanged as expected.__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "a:20, b:10, c:30\n"
     ]
    }
   ],
   "source": [
    "func(20, 10)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "__`a` & `b` can also be passed as keyword arguments. Hence `func(a=10, b=20, c=30)` works without any errors.__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "a:10, b:20, c:30\n"
     ]
    }
   ],
   "source": [
    "func(a=10, b=20, c=30)"
   ]
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   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "a:10, b:20, c:30\n"
     ]
    }
   ],
   "source": [
    "func(b=20, a=10)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "__The call `func(a=20)` gives an error because the function expects 2 positional arguments (`a` & `b`), but we are only passing one argument `a`.__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "func() missing 1 required positional argument: 'b'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-6-58396073df84>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mfunc\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0ma\u001b[0m\u001b[1;33m=\u001b[0m\u001b[1;36m10\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m: func() missing 1 required positional argument: 'b'"
     ]
    }
   ],
   "source": [
    "func(a=10)"
   ]
  }
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