17 - Lambda Functions.ipynb

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    "# Anonymous / Lambda Function"
   ]
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   "source": [
    "In Python, anonymous function is a function that is defined without a name.\n",
    "\n",
    "While normal functions are defined using the def keyword, in Python anonymous functions are defined using the lambda keyword.\n",
    "\n",
    "Lambda functions are used extensively along with built-in functions like filter(), map()"
   ]
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   "source": [
    "syntax:\n",
    "    \n",
    "    lambda arguments: expression"
   ]
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   "source": [
    "# Example:"
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      "10\n"
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    "double = lambda x: x*2\n",
    "\n",
    "print(double(5))\n"
   ]
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      "10\n"
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   "source": [
    "def double(x):\n",
    "    return x * 2\n",
    "\n",
    "print(double(5))\n"
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      "[2, 4]\n"
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   "source": [
    "#Example use with filter()\n",
    "lst = [1, 2, 3, 4, 5]\n",
    "even_lst = list(filter(lambda x: (x%2 == 0), lst))\n",
    "print(even_lst)\n"
   ]
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      "[1, 4, 9, 16, 25]\n"
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   "source": [
    "#Example use with map()\n",
    "lst = [1, 2, 3, 4, 5]\n",
    "new_lst = list(map(lambda x: x ** 2, lst))\n",
    "print(new_lst)\n"
   ]
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     "text": [
      "120\n"
     ]
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   "source": [
    "#Example use with reduce()\n",
    "from functools import reduce\n",
    "\n",
    "lst = [1, 2, 3, 4, 5]\n",
    "product_lst = reduce(lambda x, y: x*y, lst)\n",
    "print(product_lst)\n"
   ]
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