# [PYTHON MATRIX-SIG] Find/where function

**Jim Hugunin
**
hugunin@mit.edu

*Mon, 28 Oct 1996 13:05:37 -0500*

>* I would like to see the following convenience function added for
*>* returning the indices of nonzero array elements. I would prefer to
*>* call this "where" instead of "find" but "where" is already taken.
*>*
*>* def find(a):
*>* return compress(a.flat,arange(product(a.shape)))
*>*
*>* Example,
*>*
*>* b = reshape(arange(24),(2,3,4))
*>* find(b%2)
*
This is almost equivalent to the current behavior of nonzero (the only
difference is that your version works on non-flattened arrays). I'm a
little bit confused as to how this can possibly make sense for
multi-dimensional arrays, but if it does, I think it should involve an
extension of the existing nonzero function, rather than adding a new
function.
-Jim
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