How to add a value, remove a value and emptying a list???

 List has many operations to perform. The basic operations like creating a list, changing a value, displaying a list, searching an element in a list and finding length of a variable is explained in part 1.

https://www.blogger.com/blog/post/edit/5251857942821229/7649420483850529537

In part 2, the remaining operations are listed below.

  • Adding a value
  • Removing a value
  • Empty a list
  • Usage of constructor
 The operations are explained below.

  =>Adding a value:  

            This can be achieved by two ways. First one is adding a value in the end of the list. Second one  deals with adding in a specified index.

    Method1:Adding a value in the end of the list:

    colorlist=["Red", "Green", "Yellow" ]
    colorlist.append( "Orange")
    print(colorlist)

    While executing this code, you get the following output.
    [ 'Red', 'Green', 'Yellow', 'Orange' ]

    Method2: Adding an item at a specified index:

    colorlist=["Red", "Green", "Yellow" ]
    colorlist.insert( 1,"Orange")
    print(colorlist)

    The output is
     [ 'Red', 'Orange', 'Green', 'Yellow' ]   

=>Removing a value:

      When you want to delete an item, there are two method.Either ,you can delete the last item or you           can delete a specified item.

      Method1 : Remove last item:
       
      colorlist=["Red", "Green", "Yellow" ]
      colorlist.pop()
     
       It displays the output as : ['Yellow']

      Method2 : Remove a item by specified value:

      colorlist= ["Red" ,"Yellow", "Green"]
      colorlist.remove("Yellow")
      print(colorlist)

      The output is : ['Red' ,' Green' ]
       
       Method3: Remove a item by index value:

       colorlist= ["Red" ,"Yellow", "Green"]
       del colorlist[0]

       it displays [ 'Yellow', 'Green' ]    

  => Empty a list:

        When you want to clear the data in the list, use the following code.

       colorlist = ["Red", "Yellow", "Green"]
       colorlist.clear()
       print(colorlist)
 
       It clears all data in the list and prints [].

 => Usage of constructor:

        Constructor is a simple method to initialize an object. 

         colorlist= list(("Red","Green", "Yellow" ))
         print(colorlist)
     
         The output is   ['Red' ,'Green', 'Yellow']

These are second level of list operations in python.

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