[Numpy-discussion] Selecting columns of a matrix

[Johannes Loehnert]

Hi,

> I'm not sure why bool arrays cannot be used as indices.
> The "natural" solution to the original problem seemed to be:
> M[:,V>0]
> but this is not allowed.

I started a thread on this earlier this year. Try searching the archive for 
"boolean indexing" (if it comes back online somewhen).

Travis had some reason for not implementing this, but unfortunately I do not 
remember what it was. The corresponding message might still linger on my home 
PC, which I can access this evening....

Johannes