[Numpy-discussion] inplace dot products
Fri Feb 20 05:41:12 CST 2009
2009/2/20 David Warde-Farley <email@example.com>:
> Hi Olivier,
> There was this idea posted on the Scipy-user list a while back:
> but it doesn't look like he got anywhere with it, or even got a
> I just tried it and I observe the same behaviour. A quick look at the
> SciPy sources tells me there is something fishy.
> ! c = gemm(alpha,a,b,beta=0,c=0,trans_a=0,trans_b=0,overwrite_c=0)
> ! Calculate C <- alpha * op(A) * op(B) + beta * C
> I don't read Fortran very well, but it seems to me as though the
> Fortran prototype doesn't match the python prototype.
> I'll poke around a little more, but in summary: there's no numpy-
> sanctioned way to specify an output array for a dot(), AFAIK. This is
> a bit of an annoyance, I agree, though I seem to remember Robert Kern
> offering a fairly compelling argument why it's hard. I just don't know
> what that argument is :)
Alright, thanks for the reply.
Is there a canonical way /sample code to gain low level access to blas / lapack
atlas routines using ctypes from numpy / scipy code?
I don't mind fixing the dimensions and the ndtype of my array if it can
decrease the memory overhead.
BTW, Robert if your insight on this topic would be very much appreciated.
More information about the Numpy-discussion