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NNTP-Posting-Date: Tue, 06 May 2008 11:11:53 -0500
From: richardstartz@comcast.net
Newsgroups: comp.soft-sys.matlab
Subject: Speeding up sum of squares
Date: Tue, 06 May 2008 09:11:51 -0700
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I have a problem where most of the computational time is spent
computing

sum(x.^2)

where x is a vector of length between 100 and 10,000.

It seems I can speed up computation some by using 

x'*x

instead.

Any thoughts or suggestions on further speed improvement?
Thanks.
-Dick Startz

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