array manipulation without for loops

[Sheldon]

Hi Gary,

I am really trying to cut the time down as I have 600+ arrays with
dimensions (1215,1215) to compare and I do a lot more things with the
arrays. If I understand you correctly, there is no way around a for
loop?


/Sheldon

Gary Herron wrote:

> Sheldon wrote:
> > Hi,
> >
> > I have two arrays that are of the same dimension but having 3 different
> > values: 255, 1 or 2.
> > I would like to set all the positions in both arrays having 255 to be
> > equal, i.e., where one array has 255, I set the same elements in the
> > other array to 255 and visa versa. Does anyone know how to do this
> > without using for loops?
> >
> > Sincerely,
> > Sheldon
> >
> >
> Whatever for?  Have you got something against for loops?
>
> However...
>
> You could roll you own loop:
> i=0
> while i < whatever:
>     # ... do something with i
>     i += 1
>
> But what's the point?  This does the same as a for loop but slower.
>
> If you don't want any kind of a loop (again, What's the point?) you
> could write something recursive:
>
> def proc(i, ...):
>     # ... do something with i
>     if i < whatever:
>         proc(i+1, ...)
> 
> But this would be even slower.
> 
> Gary Herron