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




partial matrix operations without memory copying
Posted:
Dec 1, 2012 7:27 PM


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?



