Re: [ublas] poor vector/matrix-proxy performance

From: Gunter Winkler (gunter.winkler_at_[hidden])
Date: 2005-08-26 08:43:33

On Wednesday 24 August 2005 23:33, Christophe Prud'homme wrote:
> on a 2 years old pentium m I get these times with ublas/cvs
> and gcc version 4.0.2 20050821 (prerelease) (Debian 4.0.1-6)
>
> 1570: 1.41535e+13 (deco: 5.08 sec) (prod: 24.27 sec) 1600
> 1570: 1.41535e+13 (deco: 8.07 sec) (prod: 7.54 sec) 1600
> 0: 0 (deco: 0.22 sec) (prod: 0.07 sec) 1600
>
> Something is fishy as you can see with ublas/cvs for 1600 but otherwise the
> timings don't look too bad. Comparing with ublas/lapack binding would be
> interesting.

The matrix was too ill conditioned - I fixed this. The updated examples run 
well with gcc-3.3 and gcc-4.0. The new compiler creates much faster code and 
gives slightly more accurate results, too.

see: http://www.bauv.unibw-muenchen.de/~winkler/ublas/examples/

mfg
Gunter