On 1/28/07, Fernando Perez <[EMAIL PROTECTED]> wrote: > On 1/28/07, Keith Goodman <[EMAIL PROTECTED]> wrote: > > On 1/28/07, Fernando Perez <[EMAIL PROTECTED]> wrote: > > > [snip] The test code uses double arrays, and SSE2 has double > > > precision support but it's purely 64-bit doubles. SSE is > > > single-precision only, which means that for a double computation, > > > ATLAS isn't used and the Intel FPU does the computation instead. > > > > So since I use N.float64, ATLAS SSE won't help me? > > Well, the SSE part won't, but you're still better off with ATLAS than > with the default reference BLAS implementation. I think even an ATLAS > SSE has special code for double (not using any SSE-type engine) that's > faster than the reference BLAS which is pure generic Fortran. Someone > who knows the ATLAS internals please correct me if that's not the > case.
That makes sense. Unfortunately my simulation gives different results with and without ATLAS SSE even though the test script I made doesn't detect the difference. _______________________________________________ Numpy-discussion mailing list [email protected] http://projects.scipy.org/mailman/listinfo/numpy-discussion
