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Topic: Multiplying each colum of my matrix by a constant
Replies: 13   Last Post: Jun 15, 2013 3:54 AM

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Bruno Luong

Posts: 9,822
Registered: 7/26/08
Re: Multiplying each colum of my matrix by a constant
Posted: Jun 15, 2013 3:54 AM
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"Steven_Lord" <> wrote in message
> >
> > If I understand you correctly, this should do what you want:
> >
> > M*diag(v)

> That works in this 3-by-3 case, but you wouldn't want to do this for a very
> large matrix M and a correspondingly long v

Using sparse matrix will work fast in any case

n = size(M,2)
M * spdiags(v(:),0,n,n)

% Bruno

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