[Numpy-discussion] reshape and ravel methods of arrays now return views or raise error
oliphant at ee.byu.edu
Wed Mar 29 13:14:03 CST 2006
Christopher Barker wrote:
>>> Since fortran-strided arrays happen *all-the-time* (e.g. after a
>>> transpose operation),
> I have to wonder if it's really a good idea to do this. Why not just
> make a re-ordered copy on transpose, rather than making it Fortran
> strided? Is the optimization really that important?
And optimization is important. The _dotblas.c function for example now
works much faster with very common transpose operations because the
underlying blas knows how to deal with striding so it was a complete
wasted to always use C-ordering and get a copy of a Fortran-strided array.
On large arrays, avoiding the unnecessary copy can be very significant.
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