maximum-forward-difference.ipynb

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  "signature": "sha256:5f7441bf657e6751ef6992211a1fb7940d0c49ce2b58fb2a244a35a9f16292ba"
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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import random\n",
      "\n",
      "def maxForwardDiff1(alist):\n",
      "    maxDiff = 0\n",
      "    for i in xrange(len(alist)):\n",
      "        for j in xrange(i+1, len(alist)):\n",
      "            if (alist[i] - alist[j]) > maxDiff:\n",
      "                maxDiff = alist[i] - alist[j]\n",
      "                \n",
      "    return maxDiff\n",
      "\n",
      "def maxForwardDiff2(alist):\n",
      "    sorted_alist = sorted(alist)\n",
      "    maxDiff = 0\n",
      "    for i in xrange(0, len(alist) - 1):\n",
      "        sorted_alist.remove(alist[i])\n",
      "        if (alist[i] - sorted_alist[0]) > maxDiff:\n",
      "            maxDiff = alist[i] - sorted_alist[0]\n",
      "            \n",
      "    return maxDiff\n",
      "\n",
      "N = 1000\n",
      "alist = [random.random() for _ in xrange(N)]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%%timeit\n",
      "maxForwardDiff1(alist)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "10 loops, best of 3: 50.4 ms per loop\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%%timeit\n",
      "maxForwardDiff2(alist)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "100 loops, best of 3: 4.5 ms per loop\n"
       ]
      }
     ],
     "prompt_number": 3
    }
   ],
   "metadata": {}
  }
 ]
}