Re: uBLAS Observation: terrible execution speed for prod(matrix,prod(matrix,pro

From: tknapen (toon.knapen_at_[hidden])
Date: 2002-08-02 04:25:20

--- In Boost-Users_at_y..., Walter Bowen <yg-boost-users_at_m...> wrote:

<snip comparison performance ublas and Roguewave math.h++ >

I find it surprising that ublas can outperform math++. Nevertheless, I
think that, once you're handling matrices larger than 10x10 you should
consider calling BLAS (preferably vendor-tuned BLAS or ATLAS). During
the review, there was some discussion on the performance. Martin
Weiser for instance made this graph :
http://www.zib.de/weiser/ublas_review.gif.

Of course you need to take into account that much emphasis has been on
the interface, I figure performance optimisation will now (after the
review) be looked at in greater detail (I can't speak for Joerg and
Mathias of course but I figure they're on vacation so I wanted to give
you this feedback already anyhow). Also, you can use the BLAS-bindings
for ublas that are in the sandbox. I've only added a few BLAS-calls up
till now but will extend this to cover all of BLAS in the future. I
use these bindings myself in my projects and this provides me the rich
functionality of ublas with the performance of ATLAS.

toon