Peter Pearson wrote:
On Wed, 25 Aug 2010 06:59:36 -0700 (PDT), Carlos Grohmann wrote:
        >
I'd like to hear from you on the benefits of using numpy.power(x,y)
over (x*x*x*x..)


Using the "dis" package under Python 2.5, I see that
computing x_to_the_16 = x*x*x*x*x*x*x*x*x*x*x*x*x*x*x*x uses
15 multiplies.  I hope that numpy.power does it with 4.

Right. Square/multiply algorithm takes something like 2*(log2(y)) multiplies worst case.

That should not only be faster, but quite likely more accurate, at least for non-integer x values and large enough integer y.

DaveA
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