Cython averaging test

cython_test.ipynb

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  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%load_ext cythonmagic"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%%cython\n",
      "cimport numpy as cnp\n",
      "import numpy as np\n",
      "\n",
      "ctypedef cnp.float64_t FLOAT_t\n",
      "\n",
      "\n",
      "cpdef FLOAT_t cython_sum(cnp.ndarray[FLOAT_t, ndim=1] A):\n",
      "   cdef double [:] x = A\n",
      "   cdef double sum = 0\n",
      "   cdef unsigned int N = A.shape[0]\n",
      "   for i in xrange(N):\n",
      "     sum += x[i]\n",
      "   return sum\n",
      "\n",
      "cpdef FLOAT_t cython_avg(cnp.ndarray[FLOAT_t, ndim=1] A):\n",
      "   cdef double [:] x = A\n",
      "   cdef double sum = 0\n",
      "   cdef unsigned int N = A.shape[0]\n",
      "   for i in xrange(N):\n",
      "     sum += x[i]\n",
      "   return sum/N\n",
      "\n",
      "\n",
      "cpdef FLOAT_t cython_silly_avg(cnp.ndarray[FLOAT_t, ndim=1] A):\n",
      "   cdef unsigned int N = A.shape[0]\n",
      "   return cython_avg(A)*N"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 8
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "A = np.random.random(100000)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 11
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%timeit A.mean()"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "10000 loops, best of 3: 143 \u00b5s per loop\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%timeit cython_avg(A)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "10000 loops, best of 3: 120 \u00b5s per loop\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "%timeit cython_sum(A)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "10000 loops, best of 3: 119 \u00b5s per loop\n"
       ]
      }
     ],
     "prompt_number": 14
    }
   ],
   "metadata": {}
  }
 ]
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