newbie : array initialization, anyone ?

[arcege at shore.net]

Gerson Kurz <gerson.kurz at t-online.de> wrote:
: you can initialize a fixed-size array using something like

:   array = [0] * 10

: now, one would think that you can initialize a multidimensional array
: like this:

:   multidim = [ [0] * 10 ] * 3

: but now, all 3 elements in multidim are references to the same single
: array, so that if you type

:   multidim[0][0] = 1
:   print multidim 

: you actually get three 1 in all those 0s. Where did my thinking go
: wrong along these lines ?

This is in the FAQ (#4.50).  You will want to create each inner dimension
individually:

>>> multidim = [ None ] * 3
>>> for i in range(3):
...   multidim[i] = [ 0 ] * 10
...
>>>

  -Arcege