{
 "metadata": {
  "name": "ch15"
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": "Chapter 15 : File Input/Output and apmatrixes"
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": "example 15.1 page no : 162\n"
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": "'''\nexample 15.1 page no : 162\n'''\ntry:\n    fileName = \"a.txt\"\n    f = open(fileName,\"r\")\nexcept:\n    print \"Unable to open the file named \" , fileName;\n    import sys\n    sys.exit(0)\n\n# reading file line by line\n    \nfor i in f.readlines():\n    print i\n\nf.close()    ",
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "ename": "SystemExit",
       "evalue": "0",
       "output_type": "pyerr",
       "traceback": [
        "An exception has occurred, use %tb to see the full traceback.\n",
        "\u001b[1;31mSystemExit\u001b[0m\u001b[1;31m:\u001b[0m 0\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": "Unable to open the file named  a.txt\n"
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": "To exit: use 'exit', 'quit', or Ctrl-D.\n"
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": "example 15.2 page no : 163\n"
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": "'''\nexample 15.2 page no : 163\n'''\n\ntry:\n    fileName = \"a.txt\"\n    outputFile = \"b.txt\"\n    f = open(fileName,\"r\")\n    w = open(outputFile,\"w\")\nexcept:\n    print \"Unable to open the file named \" , fileName;\n    import sys\n    sys.exit(0)\n\n# reading file line by line\n    \nfor i in f.readlines():\n    w.write(i)\n    print i\n    \nf.close()\nw.close()    ",
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "ename": "SystemExit",
       "evalue": "0",
       "output_type": "pyerr",
       "traceback": [
        "An exception has occurred, use %tb to see the full traceback.\n",
        "\u001b[1;31mSystemExit\u001b[0m\u001b[1;31m:\u001b[0m 0\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": "Unable to open the file named  a.txt\n"
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": "To exit: use 'exit', 'quit', or Ctrl-D.\n"
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": "example 15.3 page no : 167\n"
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": "'''\nexample 15.3 page no : 167\n'''\n\nclass Set:\n    def __init__(self,n):\n        self.elements = []\n        self.numElements = 0\n\n    def getNumElements(self):\n        return self.numElements\n\n    def getElement(self,i):\n        if (i < self.numElements):\n            return slef.elements[i];\n        else:\n            print \"Set index out of range.\" \n            import sys\n            sys.exit(0)\n\n    def find(self,s):\n        for i in range(self.numElements):\n            if (self.elements[i] == s): \n                return i;\n        return -1;\n\n    def add(self,s):\n        # if the element is already in the set, return its index\n        index = self.find(s);\n        if (index != -1):\n            return index;\n        # if the apvector is full, double its size\n        # add the new elements and return its index\n        self.elements.append(s)\n        self.numElements += 1\n        return self.numElements - 1;\n\ncities= Set (2);\ncity1 = 'ahmedabad'\ncity2 = 'rajkot'\nindex1 = cities.add(city1);\nindex2 = cities.add(city2)\nprint index1, index2",
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": "0 1\n"
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": "",
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": "",
     "language": "python",
     "metadata": {},
     "outputs": []
    }
   ],
   "metadata": {}
  }
 ]
}