[Numpy-discussion] python numpy code many times slower than c++

Robert Kern robert.kern@gmail....
Thu Jan 22 01:52:32 CST 2009

On Thu, Jan 22, 2009 at 01:46, Hanni Ali <hanni.ali@gmail.com> wrote:
> I have been using your profiler extensively and it has contributed to my
> achieving significant improvements in the application I work on largely due
> to the usefulness of the line by line breakdown enabling me to easily select
> the next part of code to work on optimizing. So firstly many thanks for
> writing it.

My pleasure.

> However back to my point, Wes, I have also experienced timing oddities, in
> particular on Virtual machines (MS Hyper-V has very poor processor timings,
> the older MS VM works fine though). I believe the negative timings arise
> when the CPU (be it virtual or possibly physical) deviates from its standard
> performance or rather the initial timer unit taken, would this make sense to
> you Robert?

Can you try using cProfile with lots of calls to empty functions? I'm
using the same timer functions as cProfile.

Robert Kern

"I have come to believe that the whole world is an enigma, a harmless
enigma that is made terrible by our own mad attempt to interpret it as
though it had an underlying truth."
  -- Umberto Eco

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