Enumerate.ipynb

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    "#enumerate()\n",
    "\n",
    "In this lecture we will learn about an extremely useful built-in function: enumerate(). Enumerate allows you to keep a count as you iterate through an object. It does this by returning a tuple in the form (count,element). The function itself is equivalent to:\n",
    "\n",
    "    def enumerate(sequence, start=0):\n",
    "        n = start\n",
    "        for elem in sequence:\n",
    "            yield n, elem\n",
    "            n += 1\n",
    "\n",
    "##Example"
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      "0\n",
      "a\n",
      "1\n",
      "b\n",
      "2\n",
      "c\n"
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   "source": [
    "lst = ['a','b','c']\n",
    "\n",
    "for number,item in enumerate(lst):\n",
    "    print number\n",
    "    print item"
   ]
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   "source": [
    "enumerate() becomes particularly useful when you have a case where you need to have some sort of tracker. For example:"
   ]
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      "a\n",
      "b\n"
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   "source": [
    "for count,item in enumerate(lst):\n",
    "    if count >= 2:\n",
    "        break\n",
    "    else:\n",
    "        print item"
   ]
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   "source": [
    "Great! You should now have a good understanding of enumerate and its potential use cases."
   ]
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