From: Riccardo Rossi (rrossi_at_[hidden])
Date: 2007-02-16 02:03:56
if i may drop in ... this (in attachment) is the code i use for
doing the operation you want to do. I am not really a ublas expert so i
can not guarantee it is the optimal way, nevertheless it works and it is
the drawback is that it is needed to precalculate the zero pattern of
the "output matrix"