Re: indexing expression performance

[Francesco Potortì]

>You may also be interested in the most recent indexing improvements:
>http://hg.savannah.gnu.org/hgweb/octave/rev/ad3afaaa19c1
>http://www.nabble.com/lazy-contiguous-subrange-indexing-td21458811.html
>
>this will cheat your first loop to run in almost zero time...

This is very interesting.  In fact, I routinely extract (usually memory
contiguous) 2-d slices from a big multidim matrix to sum them, without
ever writing to the matrix.  To work around the slow indexing problem, I
resorted to the linear indexin trick, followed by resizing.  I think the
above improvements will significantly speed up my code, which is
important to me as I extract a big number of slices to make Montecarlo
computations.

Thanks again :)

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