how to access elements in a 2D array?

Question

I am new to python and I would like to understand how one goes about manipulating the elements of an array. If I have for example:

a= ( a11 a12 a13 )  and b          


        

Answer 1

If you have this :

a = [[1, 1], [2, 1],[3, 1]]

You can easily access this by using :

print(a[0][2])
a[0][1] = 7
print(a)