hpc gfortran

[vincent habchi]

> Thanks for the tip, I'll have a look.

You’re welcome. BTW, atlas defaults now to clang-mp-3.3 for AVX-enabled computers (from mid-2011 on) since it is the only compiler with full AVX support available on MacOS. Gfortran is plagued, as well as GCC, by a dependency on the outdated version of the system as(1), and prior versions of clang are buggy. 

Using AVX instead of SSE doubles throughput on some core matrix operations, which is a substantial gain.

Vincent