On Tue, 01 Jun 2010 02:05:35 +0200, Christopher O'Brien <cjobrien at ncsu.edu> wrote: > Perhaps the most disturbing were those involving simple SCF calculations > such as: >> Checking atom-pbe...discrepancy in pressure detected >> Reference: -14.44, You got: -14.43 >> Checking atom-sigmapbe...discrepancy in pressure detected >> Reference: -15.02, You got: -15.03
Dear Christopher, I wouldn't worry about such a discrepancy. Those test involve isolated atoms, where pressure is not really meaningful. In general, different optimized algebraic libraries (ATLAS, MKL, ACML...) use different tricks to increase performance but, as a trade-off, they are not alway consistent. This introduces some noise in the parts of the code that are more sensible to it, especially pressure. 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/
