python declare list of size n code example

Example 1: python initialize list length n

Creating an empty list:

>>> l = [None] * 10
>>> l
[None, None, None, None, None, None, None, None, None, None]

Example 2: create a list of a certain length python

# 2.X only. Use list(range(10)) in 3.X.
>>> l = range(10)
>>> l
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Example 3: python declare array of size n

>>> n = 5                     #length of list
>>> list = [None] * n         #populate list, length n with n entries "None"
>>> print(list)
[None, None, None, None, None]

>>> list.append(1)            #append 1 to right side of list
>>> list = list[-n:]          #redefine list as the last n elements of list
>>> print(list)
[None, None, None, None, 1]

>>> list.append(1)            #append 1 to right side of list
>>> list = list[-n:]          #redefine list as the last n elements of list
>>> print(list)
[None, None, None, 1, 1]

>>> list.append(1)            #append 1 to right side of list
>>> list = list[-n:]          #redefine list as the last n elements of list
>>> print(list)
[None, None, 1, 1, 1]

Example 4: python list of size

li = [None] * 5 # [None, None, None, None, None]
li = [0] * 5 # [0, 0, 0, 0, 0]