From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Why is sparse * 3D full array allowed?
Date: Fri, 16 Oct 2009 13:56:18 +0000 (UTC)
Organization: Boeing
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References: <hb948j$28q$> <hb96n9$5og$>
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"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <hb96n9$5og$>...
> "James Tursa" <> wrote in message <hb948j$28q$>...
> > I noticed that if a sparse matrix is multiplied by a full nD matrix that can be squeezed to a 2D matrix, the multiplication takes place by doing the squeeze. 
> To be more precise, the right (multi-dimensional) array F will be reshaped as
> F = reshape(F, size(F,1), []) 
> before the product S*F takes place.
> The same reshaped is carried out with left product full/sparse. F*S is done as following:
> F = reshape(F, size(F,1), [])  * S
> Bruno

Thanks for the correction. It looked like a squeeze last night but I now realize it was just my screen display wrapping around.

James Tursa