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Topic: MTIMESX when Inner matrix dimensions are not agree.
Replies: 11   Last Post: Apr 18, 2013 2:19 PM

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ghasem

Posts: 79
Registered: 4/13/13
Re: MTIMESX when Inner matrix dimensions are not agree.
Posted: Apr 18, 2013 8:28 AM
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> No you didn't, since you ask about "matrix dimension must agree" error.
>
> And you start over again with mmx.
>
> Bruno

=================================
yes,I know,but you don't understand my question.
in fact,my question was as follow:
if I want to use from MTIMESX for fast opertaion,but second dimension of A is not equal with first diemnsion of B,but second and third dimensions in both A and B are same,is a good choice MTIMESX?
for example:
a=rand(33,32,32);
b=rand(33,32,32);
I konw that : c = mtimesx(a,b) => is false!
also,I know that simply : c =a.*b
but I want to use from:
c = permute(mtimesx(permute(a,[2 3 1]),permute(b,[2 3 1])),[3 1 2]);
NOW,my question was:
between " .* " operator and " mtimesx (or mmx)" , which is faster?
ghasem



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