On Fri, Jun 11, 2010 at 22:06, <jordan@math.ucsb.edu> wrote:

Hi all,

I recently needed to a simple array procedure that I assumed would be supported (and almost is) but was surprised to find some limitations.

I've got two arrays, A and B, and some array of indices, I, and I want to perform the operation

A[I] += B

where I and B have the same dimensions.

This works fine provided there are no repeated indices in I, but otherwise only the last of each repeated index is used. I've written a C function I call PutSum that does what I want, but I figured there must something already lying around. Is there?

numpy.bincount() -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco