Week-02-02-Loops

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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 3\n",
      "for i in range(5):\n",
      "    print i\n",
      "    print i**2\n",
      "    print i*i*i"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 4\n",
      "n = input(\"How many numbers do you have? \")\n",
      "summ = 0.0\n",
      "for i in range(n):\n",
      "    x = input(\"Enter a number >> \")\n",
      "    summ = summ + x\n",
      "print(\"\\nThe average of the numbers is\", summ / n)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 5\n",
      "for x in range(0, 4, 2):\n",
      "    print \"This is index %d\" % (x)\n",
      "for x in range(7, 0, -3):\n",
      "    print \"This is index %d\" % (x)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 6\n",
      "for x in xrange(0, 5):\n",
      "    for y in xrange(0, 5):\n",
      "        print '%d * %d = %d' % (x, y, x*y)\n",
      "\n",
      "for x in xrange(300000):\n",
      "    print x\n",
      "    if x == 11:\n",
      "        break"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 7\n",
      "# ****** Do this in spyder ******\n",
      "# Create a text file iand save it in the same folder where your prgrams are\n",
      "# The text file containss three lines and is called myfile.txt\n",
      "# Hello\n",
      "# Hi\n",
      "# OK\n",
      "\n",
      "f = open(\u201cmyfile.txt\")\n",
      "for line in f: \n",
      "    print \">\", line\n",
      "\n",
      "mystring = \"Hello there\"\n",
      "for x in mystring:\n",
      "    print x\n",
      "\n",
      "# iterating through a list\n",
      "mycollection = ['Hello', True, 5, 5.0, (2,3)]\n",
      "for x in mycollection:\n",
      "    print x\n",
      "    \n",
      "# iterating through a dictionary\n",
      "d = { 'a': 1, 'b': 2, 'c': 3, }\n",
      "for v in d:\n",
      "    print v\n",
      "# Note the strange order!"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 8\n",
      "i = 0\n",
      "while i <= 10:\n",
      "    print(i)\n",
      "    i = i + 1\n",
      "\n",
      "for i in\n",
      "range(11):\n",
      "    print(i)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 9\n",
      "summ = 0.0\n",
      "count = 0\n",
      "x = int(raw_input(\"Enter an integer (negative to quit) >> \"))\n",
      "while x >= 0:\n",
      "    summ = summ + x\n",
      "    count = count + 1\n",
      "    x = int(raw_input(\"Enter an integer (negative to quit) >> \"))\n",
      "print(\"\\nThe average of the numbers is\", summ / count)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 10\n",
      "# ****** Do this in spyder ******\n",
      "# Create file with one number on each line. \n",
      "fileName = raw_input(\"What file are the numbers in? \")\n",
      "infile = open(fileName,'r')\n",
      "sum = 0.0\n",
      "count = 0\n",
      "for line in infile.readlines():\n",
      "    sum = sum + float(line)\n",
      "    count = count + 1\n",
      "print(\"\\nThe average of the numbers is\", sum / count)\n",
      "close(infile)\n",
      "\n",
      "# ****** Do this in spyder ******\n",
      "# Create file with one number on each line. The last line should be blank.\n",
      "# That is the sentinak character. The while statement checks for that\n",
      "fileName = raw_input(\"What file are the numbers in? \")\n",
      "infile = open(fileName,'r')\n",
      "sum = 0.0\n",
      "count = 0\n",
      "line = infile.readlines()\n",
      "while line != \"\":                  # This is the check for the sentinel character\n",
      "    sum = sum + float(line)\n",
      "    count = count + 1\n",
      "    line = infile.readlines()\n",
      "print(\"\\nThe average of the numbers is\", sum / count)\n",
      "close(infile)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 11\n",
      "# Create file with one number on each line. The last line should be blank.\n",
      "# That is the sentinak character. The if statement checks for that\n",
      "fileName = raw_input(\"What file are the numbers in? \")\n",
      "infile = open(fileName,'r')\n",
      "sum = 0.0\n",
      "count = 0\n",
      "line = infile.readline()\n",
      "while line != \"\":\n",
      "    for xStr in line.split(\",\"):\n",
      "        sum = sum + float(xStr)\n",
      "        count = count + 1\n",
      "    line = infile.readline()\n",
      "print(\"\\nThe average of the numbers is\", sum / count)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 12\n",
      "# First Example\n",
      "for letter in 'Python': \n",
      "if letter == 'h':\n",
      "      break\n",
      "   print 'Current Letter :', letter\n",
      "\n",
      "# Second Example\n",
      "var = 10                    \n",
      "while var > 0:              \n",
      "   print 'Current variable value :', var\n",
      "   var = var -1\n",
      "   if var == 5:\n",
      "      break\n",
      "print \"Good bye!\"\n",
      "mycollection = ['Hello', True, 5, 5.0, (2,3)]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 13\n",
      "# First Example\n",
      "for letter in 'Python':\n",
      "   if letter == 'h':\n",
      "      continue\n",
      "   print 'Current Letter :', letter\n",
      "\n",
      "# Second Example\n",
      "var = 10\n",
      "while var > 0:              \n",
      "   var = var -1\n",
      "   if var == 5:\n",
      "      continue\n",
      "   print 'Current variable value :', var\n",
      "print \"Good bye!\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Slide 15\n",
      "mylist = [1,2,4,3,5,6]\n",
      "for anelement in mylist:\n",
      "    if anelement % 2 == 0:\n",
      "        print \"list contains an even number\"\n",
      "        break\n",
      "else:\n",
      "    print \"list does not contain an even number\" "
     ],
     "language": "python",
     "metadata": {},
     "outputs": []
    }
   ],
   "metadata": {}
  }
 ]
}