2d array of lists in python

Question

I am trying to create a 2d matrix so that each cell contains a list of strings. Matrix dimensions are known before the creation and I need to have access to any element from

Answer 1

Just as you wrote it:

>>> matrix = [["str1", "str2"], ["str3"], ["str4", "str5"]]
>>> matrix
[['str1', 'str2'], ['str3'], ['str4', 'str5']]
>>> matrix[0][1]
'str2'
>>> matrix[0][1] += "someText"
>>> matrix
[['str1', 'str2someText'], ['str3'], ['str4', 'str5']]
>>> matrix[0].extend(["str6"])
>>> matrix[0]
['str1', 'str2someText', 'str6']

Just think about 2D matrix as list of the lists. Other operations also work fine, for example,

>>> matrix[0].append('value')
>>> matrix[0]
[0, 0, 0, 0, 0, 'value']
>>> matrix[0].pop()
'value'
>>>