On Mon, Jan 04, 2010 at 10:24:01PM +0100, Garth N. Wells wrote: > > > Anders Logg wrote: > > On Sun, Jan 03, 2010 at 03:38:19PM +0100, Garth N. Wells wrote: > >> It would be useful to have an efficient and simple data structure for > >> small and large dense matrices with lots of functionality. We have > >> uBLAS, but I'm not convinced of its efficiency for small matrices, and > >> it doesn't interface to LAPACK, which is why LAPACKMatrix was added. > >> > >> There are a few libraries around that provide expression templates (for > >> nice syntax) and LAPACK/ATLAS interfaces, see for example > >> > >> http://arma.sourceforge.net/ > >> > >> I think that wrapping such a library would be very useful and could be > >> better that having LAPACKMatrix, etc. > >> > >> Garth > > > > Agree. I was thinking of wrapping a suitable library before adding > > LAPACKMatrix, but it was too much effort at the time. > > > > Even less effort for your solvers would be to use Armadillo directly. > It's available as a package through apt-get.
Yes, we should use the solvers also. That's one of the major points to get all LAPACK functionality for free, not just bits of it. > > Incidentally, I also looked at Armadillo as the main candidate for > > wrapping. > > > > I converted the fenics-plasticity solve from uBLASDenseMatrix to > Armadillo yesterday, and got a total solve time speed up of 100%. This > includes assembly, etc, so I expect the code that uses dense matrices is > an order of magnitude faster. From some simple tests, matrix inversion > in Armadillo was about 35 times faster that uBLASDenseMatrix, and the > syntax is nicer than uBLAS. Addition, etc, was also much faster with > Armadillo. Impressive. -- Anders
signature.asc
Description: Digital signature
_______________________________________________ Mailing list: https://launchpad.net/~dolfin Post to : dolfin@lists.launchpad.net Unsubscribe : https://launchpad.net/~dolfin More help : https://help.launchpad.net/ListHelp
