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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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 Alan Weiss Posts: 1,374 Registered: 11/27/08
Re: Multiplying each colum of my matrix by a constant
Posted: Jun 12, 2013 10:48 AM

On 6/11/2013 4:59 PM, Wanderson wrote:
> Hello there,
>
> I'm trouble here, I'm sure that the solution isn't too hard to my
> problem, but I'm really stucked here and I can't see the light in end
> of the tunnel right now.
>
> I have matrix 3x3 and a vector 1x3 and I want to multiply each column
> of my matrix by each element of my vector, for example:
>
> If my matrix 3x3 is called M and my vector v is a 1x3 dimension:
> M(:,1) = M(:,1).*v(1);
> M(:,2) = M(:,2).*v(2);
> M(:,3) = M(:,3).*v(3);
>
> Ofc, I want to avoid use 'for loops'.
>
> Thx.

If I understand you correctly, this should do what you want:

M*diag(v)

Alan Weiss
MATLAB mathematical toolbox documentation

Date Subject Author
6/11/13 Wanderson
6/11/13 dpb
6/11/13 Wanderson
6/11/13 dpb
6/11/13 Wanderson
6/11/13 dpb
6/12/13 dpb
6/12/13 Wanderson
6/12/13 Wanderson
6/12/13 dpb
6/12/13 Alan Weiss
6/12/13 dpb
6/13/13 Steven Lord
6/15/13 Bruno Luong