Re: [ublas] faster inplace_solve implementation (triangular.hpp)

Subject: Re: [ublas] faster inplace_solve implementation (triangular.hpp)
From: Jörn Ungermann (j.ungermann_at_[hidden])
Date: 2010-03-17 17:33:46

Hi Nasos!

On Wed, 2010-03-17 at 20:59 +0100, Nasos Iliopoulos wrote:
> I did a quick run and I wonder if you run the tests with optimization
> flags on (although with them on I get the same speedup but about 10
> times faster overall), usually I use:
> -O2 -DNDEBUG -msse3 -mfpmath=sse -ftree-vectorize
> -ftree-vectorizer-verbose=1
We use similar flags for our production code, but I compiled the test
without any flags. It should just show that the algorithm itself is
superior. The actual speedup itself is highly dependent on the problem
size and the amount of non-zeros, i.e. my proposal gets better the
larger and/or non-sparse the matrix gets.

> There are tests in boost-trunk/libs/numeric/ublas/test, but I think
> they will need a rewrite some time in the future. An assertion over an
> L-n norm (like you have) would probably be a good candidate for such
> tests.
Thanks for the hint, I didn't look in the libs directory for the
tests...

Kind regards,
Jörn

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