Re: Not where

[davidf(at)dfanning.com (David Fanning)]

Kenneth P. Bowman (bowman@null.edu) writes:

> I often find myself using WHERE to divide an array into two parts.  I do
> one operation on the first part and a different operation on the second
> part.
> 
> It would be nice to have an auxiliary array containing all the indices
> that are *not* returned by WHERE in i.  For example, it would be nice to
> do
> 
> a = FLTARR(...)
> i = WHERE((a...), count, NOT_WHERE = j, NOT_COUNT = not_count)
> IF (count     GT 0L) THEN a[i] = ...
> IF (not_count GT 0L) THEN a[j] = ...
> 
> Lacking the above changes to WHERE, can anyone suggest a fast and easy way
> to get j=NOT(i) ?

Now *here* is a place where Alex's matrix operations will
really pay off!

I'll leave it to Alex to handle this question. :-)

Cheers,

David

-- 
David Fanning, Ph.D.
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