Dave, I think BrowserUK's point was functional efficiency as opposed to operators. The matrices in question had values that were zeroes and ones only, probably connectivity matrices from some kind of graph. As such they can be implemented within regular Perl via bit-vectors, and such an implementation is both space efficient and fast.
PDL, and I may be wrong here, is optimized for floating point efficiency. I'd be happy to be proven wrong in this, but I think, if you get past all the extraneous questions about operators in PDL, that the compact expression of 0 & 1 only matrices as bit-vectors was at the heart of UK's comments. That you could count bit wise operations with something like this one liner my $count = sum ($poweroftwo & $My_PDL_Matrix ) >> $power; Is yet another issue. Sincerely, David Myers (dwm042@perlmonks). CPAN ID DWMYERS _______________________________________________ Perldl mailing list [email protected] http://mailman.jach.hawaii.edu/mailman/listinfo/perldl
