Page 312 - AI Ver 1.0 Class 9
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Creating a list of students with roll no  students = [21, "Gunjan", 94.5, 34, "Rohit",
           and percentage (list of mixed values)  91.3]
           Creating a list within another list    section = ["A", 25, "English", ["B",34], ["C",37],
                                                  56.7]
           Creating a list with repeated values   L1 = [10] * 5   # L1 will have [10, 10, 10, 10,

                                                  10]
           Creating  a  list  from  another  sequence  alpha = list("hello") #string converted to a
           or string using list( ) function       list #output will [‘h’, ‘e’, ‘l’, ‘l’, ‘o’]
           Values input from the user in a list   L1 = list(input("enter numbers :"))


        Accessing the Elements of a List

        The elements of a list can be accessed by using its index number starts with 0 (zero). There are two different
        ways of using the index number:

           • Forward Indexing: The index number begins with 0 till length-1 and we refer the elements from left to right.
           • Negative/Backward Indexing: The index number begins with -1 till -length and we refer the elements from
           right to left. For example,
                    L1 = ['P', 'Y', 'T', 'H', 'O', 'N']


                     Forward Indexing         0     1    2     3    4    5
                                              P     Y    T    H     O    N

                                              –6   –5    –4   –3   –2    –1      Backward Indexing

        Each element can be accessed by using:

           listname[index number]
                                          Commands                                Output

                        print(L1[0])                                     P
                        print(L1[3])                                     H
                        print(L1[-3])                                    H
                        print(L1[-1])                                    N

                        print(L1)      #print complete list              ['P', 'Y', 'T', 'H', 'O', 'N']
                        print(L1[0], L1[4])                              P O

        Traversing a List

        Traversing means visiting each element and processing it as required by a program. We use a loop to traverse a
        list. There are different ways of visit each element as shown below:

                                           Commands                                         Output

              L1=['P', 'Y', 'T', 'H', 'O', 'N']                                     P ! Y ! T ! H ! O ! N !
              for eachvalue in L1:

                  print(eachvalue, end="!")





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