replace deepest level of nested list

[Michael Spencer]

David Isaac wrote:
> Thanks to both Roberto and George.
> I had considered the recursive solution
> but was worried about its efficiency.
> I had not seen how to implement the numpy
> solution, which looks pretty nice.
> 
> Thanks!
> Alan
> 
> 
You could also use pyarray, which mimics numpy's indexing, but uses native 
python lists as the data store.

So...

 >>> from pyarray import ndlist
 >>> source = 
ndlist([[['r00','g00','b00'],['r01','g01','b01']],[['r10','g10','b10'],['r11','g11'
... ,'b11']]])
 >>> source
array([[[r00, g00, b00],
         [r01, g01, b01]],

        [[r10, g10, b10],
         [r11, g11, b11]]])
 >>> source[...,0]  # note elipsis means skip all but the last dimension
array([[r00, r01],
        [r10, r11]])
 >>> _.tolist()
[['r00', 'r01'], ['r10', 'r11']]
 >>>

pyarray (single pure-python module) can be downloaded from:

http://svn.brownspencer.com/pyarray/trunk/

Regards

Michael