How to make arrays from Lists

[bearophileHUGS at lycos.com]

gc_ott:
> How do I change the value of any element to produce (say)
> [[99,0,0],[0,0,0],[0,0,0]] ?
>
> gordc

To create a 2D list, that is a list of lists:
x = [[0] * ncols for i in nrows]
(Don't do what you were doing, because you end with many references to
the same list, and that will give you troubles.)

To set an item you do just:
x[0][0] = 99

Bye,
bearophile