Page 239 - Computer Science Class 11 With Functions
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Note that the function call range(30, 10) returns an empty sequence as we cannot count up from 30 to 10.
              Similarly, the function call range(10, 30, -2) returns an empty sequence because we cannot count down from
              10 to 30 (in steps of -2).

                                                   Table 10.1: Use of range()
                   Function call                Sequence                               Explanation
             range(2, 10, 1)          [2, 3, 4, 5, 6, 7, 8, 9] start value is 2
                                                                     last value is 9 (=10-1)
                                                                     step value is +1

             range(-3, 3)             [-3, -2, -1, 0, 1, 2]          start value is -3
                                                                     last value is 2 (=3-1)
                                                                     step value is +1 (default)
             range(10, 20, 2)         [10, 12, 14, 16, 18]           start value is 10
                                                                     last value is 18 (last in sequence before 20)

                                                                     step value is +2
             range(20, 14, -1)        [20, 19, 18, 17, 16,  start value is 20
                                      15]                            last value is 15 (last in sequence before 14)
                                                                     step value is -1

             range(20, 10)            []                             start value is 20
                                                                     Unable to count from 10 up to 10 (default step value
                                                                     is +1)

             range(7)                 [0, 1, 2, 3, 4, 5, 6]          start value is 0 (default)
                                                                     last value is 6 (=7-1),
                                                                     step up is +1(default)
             range(5, 10, 0)          Value error                    For counting, step value must be a non-zero integer.
             range(10, 30, 0.5)       Value error                    For counting, step value must be a non-zero integer.



                    Write the sequence of values that the following function call will return:
                    1.  range(1,14,3)
                    2.  range(100,85,5)
                    3.  range(100,85,-5)
                    4.  range(5)
                    5.  range(5,8)



            10.3 for Statement

            Now we are ready to illustrate how we can use Python's for statement to shorten Program 10.1 and its extensions
            to compute the average marks of a large number of students (see Program 10.2). This program accepts the number
            of students (nStudents) as a variable (line 10). So, there is no need to modify the program when the number of
            students changes. Suppose, the user enters the number 6 as the value of nStudents. The for statement in the
            program comprises:
              A header part (line 11), i.e.,

              for count in range(0, nStudents):

                                                                                              Looping in Python  237
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