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Topic: subtract vector from matrix rows without for loop
Replies: 13   Last Post: Jun 14, 2017 7:34 AM

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Posts: 5
Registered: 7/31/11
Re: subtract vector from matrix rows without for loop
Posted: Dec 6, 2012 11:49 PM
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"Matt J" wrote in message <hesupb$i07$>...
> "Patrick Diviacco" <> wrote in message <hesm3s$3sn$>...
> > hi,
> >
> > can I subtract the same vector to each row of a matrix without using a for loop ?
> > thanks

> For loops may be optimal (looping along the smallest dimension of the matrix), when the smallest dimension is small enough.

I like Matt's answer... here is another way of doing it, slightly more efficient.

A = magic(3);
B = [ 1 2 3];
C = A-diag(B)*ones(size(A));

In essence is the same thing.

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