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Subject: Re: Minor disappointment with Matlab
Date: Tue, 8 Sep 2009 18:52:02 +0000 (UTC)
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"James Tursa" <aclassyguy_with_a_k_not_a_c@hotmail.com> wrote in message <h8688g$bm8$1@fred.mathworks.com>...
> >> tic;a'*b;toc
> Elapsed time is 0.302599 seconds.
> >> tic;dot(a,b);toc
> Elapsed time is 0.774087 seconds.

P.S. I should mention that the main reason for this speed difference seems to be that the BLAS calls behind the matrix multiply are multi-threaded (at least in later versions of MATLAB) whereas the simple loop used in the dot function is not. 

James Tursa