On Wed, 13 Jan 2010 16:51:20 +0100, Iain Bethune <ibethune at staffmail.ed.ac.uk> wrote: > Any idea what might be causing this?
Hi Iain, are you using "vanilla" FFTW libraries or architecture optimized ones? (e.g. ACML, ESSL) Some high performance libraries can trade a little of accuracy for speed, and to be honest. I'm not even sure that perfect matching (whatever the definition of perfect) is guaranteed even with the standard open-source FFTW libraries. best regards -- Lorenzo Paulatto *** Note: my affiliation has changed! please send future correspondence to: <Lorenzo.Paulatto at impmc.upmc.fr> *** post-doc @ IMPMC/UPMC - Universit? Paris 6 phone: +33 (0)1 44 27 74 89 www: http://www-int.impmc.upmc.fr/~paulatto/ previously: phd student @ SISSA & DEMOCRITOS (Trieste) phone: +39 040 3787 511 www: http://people.sissa.it/~paulatto/
