[Numpy-discussion] numpy and roundoff(?)
Mon Mar 3 11:52:42 CST 2008
Damian Eads wrote:
> At work we noticed a significant difference in results occurring in two
> versions of our code, an earlier version written in C++, and a later
> version written in Python/numpy. The algorithms were structured about
> the same. My colleague found the cause of the discrepancy; it turned out
> to be a difference in the way numpy and the C++ program were compiled.
> One used -mfpmath=sse, and the other, -mfpmath=387. Keeping them both
> the same cleared the discrepancy.
Was it really a "significant" difference, or just noticeable? I hope
not, that would be pretty scary!
Christopher Barker, Ph.D.
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