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From: Fernando P. <Fer...@co...> - 2006-01-18 22:51:43
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David M. Cooke wrote: > I've done a little bit of work along these lines. I have a module I > call vector3 [*] which has 2- and 3-dimensional immutable vectors, > using either ints or doubles. It's as fast as I could make it, while > keeping it all written in Pyrex. I find it very convenient for > anything vector-related. Konrad Hinsen has something similiar in the > development version of his ScientificPython package. > > [*] http://arbutus.mcmaster.ca/dmc/software/vector3.html > > Also, I've also done some playing around with a n-dimensional vector > type (restricted to doubles). My best attempts make it ~4-5x faster > than numpy (and 2x faster than Numeric) for vectors of dimension 10 > on simple ops like + and *, 2x faster than numpy for dimension 1000, > and approaching 1x as you make the vectors larger. Indexing is about > 3x faster than numpy, and 1.4x faster than Numeric. So that gives I > think some idea of the maximum speed-up possible. > > I think the speedups mostly come from the utter lack of any > polymorphism: it handles vectors of doubles only, and only as > contiguous vectors (no strides). This is excellent, thanks for the pointer. I can see uses for vectors (still 1-d, no strides, etc) with more than 3 elements, and perhaps fixed-size (no reshaping, no striding) 2-d arrays (matrices), but this looks like a good starting point. Sandbox material? Cheers, f |