Lists

Question

If I create a list and, let's say, I want to add a few more integers in the list, how should I do that?
For eg: a="Babu"
a=list(a)
now let's say I want to insert the integer 3 in the list. How do I do that?

Answer 1

There are actually 3 methods of adding elements to a list:

list.append(elem) -- adds a single element to the end of the list. Common error: does not return the new list, just modifies the original.

list.insert(index, elem) -- inserts the element at the given index, shifting elements to the right.

list.extend(list2) adds the elements in list2 to the end of the list. Using + or += on a list is similar to using extend().

a = "Babu"
a = list(a)
print(a)
['B', 'a', 'b', 'u']
a.insert(1,"X")
print(a)
['B', 'X', 'a', 'b', 'u']
a.extend(["L", "M", "N"])
print(a)
['B', 'X', 'a', 'b', 'u', 'L', 'M', 'N']

Answer 2

a.append(3)

this will add the number 3 at the end of your list

Answer 3

In fact, there's a fourth way of adding elements to list: the list concanetation ability trough the use of the simple '+' operator...

mylist = [1,2,3,4]
mylist = mylist + [5,6,7]

... after what 'mylist' is equal to [1,2,3,4,5,6,7]

Obviously, you can use it with list litteral as with list variable names ^^