Anatoly Yakovenko
https://gist.github.com/aeyakovenko/bf558697a0b3f377f9e8
so i am seeing basically results with N4 that are as good as using sequential computation on my macbook for the matrix multiply algorithm. any idea why?
Thanks, Anatoly
Hi Anatoly, repa is good for things that live on a grid e.g. forward / backward Euler, Crank Nicholson, convolution e.g. of images, multi-grid methods where each cell is updated based on local information (so we are in the world of comonads). I imagine it would also be good for Ising models (but maybe using Swendson-Yang or Wolff). It is not good where the update is based on global information e.g. simulating the solar system. You might compare your results in repa againt yarr https://hackage.haskell.org/package/yarr. Here are some examples of repa / yarr that could be of use https://idontgetoutmuch.wordpress.com/2014/02/10/ laplaces-equation-in-haskell-using-a-dsl-for-stencils-3/ https://idontgetoutmuch.wordpress.com/2013/08/06/ planetary-simulation-with-excursions-in-symplectic-manifolds-6/ https://idontgetoutmuch.wordpress.com/2013/02/10/ parallelising-path-dependent-options-in-haskell-2/ https://readerunner.wordpress.com/2014/04/30/ multigrid-methods-with-repa/ If I knew how to cross-post this to https://mail.haskell.org/cgi-bin/mailman/listinfo/numeric when using gmane I would do so. Dominic.