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Topic: Matrix row elements manipulation
Replies: 4   Last Post: Feb 2, 2014 4:25 AM

 Messages: [ Previous | Next ]
 Milos Milenkovic Posts: 189 Registered: 4/4/09
Re: Matrix row elements manipulation
Posted: Feb 2, 2014 4:24 AM

Bruno,
thank you!

"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <lcl01p\$5jr\$1@newscl01ah.mathworks.com>...
> A=[-1 -1 -1 0 0 0 0 0 0 0 0 0 -1 -1 -1 0 0 0 0 0 0 0 0 0;
> -1 -1 -1 0 0 0 0 0 0 0 0 0 -1 -1 -1 0 0 0 0 0 0 0 0 0;
> -1 -1 -1 0 0 0 0 0 0 0 0 0 -1 -1 -1 0 0 0 0 0 0 0 0 0;
> -1 -1 -1 0 0 0 0 0 0 0 0 0 -1 -1 -1 0 0 0 0 0 0 0 0 0];
>
> % Engine
> [m, n]=size(A);
> [I, J] = ndgrid(1:m,1:n);
> J = bsxfun(@minus, J, 3*(0:m-1)'); % "3" means shift 3 positions every row
> B = zeros(size(A));
> b = J>0;
> K = sub2ind(size(B),I(b),J(b));
> B(b) = A(K)
>
> % Bruno

Date Subject Author
2/1/14 Milos Milenkovic
2/1/14 dpb
2/2/14 Milos Milenkovic
2/2/14 Bruno Luong
2/2/14 Milos Milenkovic