On Mon, Mar 2, 2009 at 09:34, Ravi <lists_r...@lavabit.com> wrote: > On Monday 02 March 2009 01:58:27 Robert Kern wrote: >> > for i in range(len(vals)): >> > flattened[idx[i]]+=vals[i] >> >> flattened[idx] = vals > > Assuming 'idx' and 'vals' are one-dimensional arrays, that should be > flattened[ idx[:numpy.size(vals)] ] += vals > or > flattened[ idx ] += vals > if 'vals' and 'idx' have the same size.
Oops. I missed the +. Actually, neither of these will work when idx has repeated indices. Instead, use: flattened += np.bincount(idx, vals) -- 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 _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
