Page 357 - Computer Science Class 11 With Functions
P. 357

Let's Summarise


              Ø   A list comprises a sequence of objects enclosed in square brackets [].

              Ø   A pair of square brackets [] denotes an empty list.
              Ø   The len() function returns the number of objects in a list.
              Ø   (+) operator is used to concatenates a pair of list.
              Ø   (*) operator produces a list, concatenated with itself a specified number of times.
              Ø   Traversing a list means accessing each element of a list. This can be  done by using looping statement, either
                  for or while.
              Ø   List Methods: Methods are defined for list objects. These methods are as follows:
                    append(elem): inserts the object elem, passed as an argument, at the end of the list.

                     insert(index,  elem): inserts the object elem, passed as an argument, at the specified index and
                    shifts the existing objects to the right.

                     extend(lst): inserts the elements in the list lst, passed as an argument, at the end of the elements
                    of the list lst.
                    index(elem): returns the index of the first occurrence of the element elem in the list.
                    reverse(): reverses the order of the elements in the list.
                    sort(): arranges the elements of the list in the ascending order.
                    remove(element): searches for the first instance of the element in the list lst and removes it.
                     pop(index): removes the element from the specified index and returns the element removed from
                    the list.
              Ø   The operator  in  checks  for  the  membership  of  a  data  object  in  the  list  and  returns  True or  False,
                  depending on whether the specified object is included in the list or not.
              Ø   The membership operator not in is used to check the membership of an element in a list. It returns True
                  if the specific element being looked for is not present in the list,  otherwise, False.
              Ø   There are various other methods available like: lem(), mean(), max(), min(), sum().
              Ø   A tuple is a sequence of elements, separated by commas and usually enclosed between parentheses().
              Ø   An empty pair of parentheses defines an empty tuple.

              Ø   A function tuple() is used to convert a sequence of elements to a tuple.
              Ø   Tuple Methods: Python provides several methods for manipulating the tuples.
                    count(element): returns the number of times the given element appears in a tuple.
                    index(element): returns the index of the first occurrence of an element in a tuple.
                    sorted(t): sorts the tuple elements in ascending order by default.






















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