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Topic: partial matrix operations without memory copying
Replies: 2   Last Post: Dec 2, 2012 6:30 AM

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Posts: 54
Registered: 5/19/10
partial matrix operations without memory copying
Posted: Dec 1, 2012 7:27 PM
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I would like to do operations on vectors of a matrix efficiently, without memory copying.
For example, say V is KxK, A is Nxp p>k
I want to do X(:,1:K)*V efficiently. As it is currently written, matlab makes a temporary copy of the first K colomns of X and does the multiplication. The primitive BLAS routines can handle this without memory copying: just give it the same pointer to X with different number of columns as input. I would like to realize this speedup without having to go to mex. Is this possible?

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