Fill matrix with values from other, smaller matrix

Question

I have a matrix A:

A = [-10 10];

And I'd like to create B like this:

with d rows.

I tried:

B(1:d)=A(:);

to fill rows from 1 to d with A and a few other combinations, but I can't make it work. How can I achive this?

use the [`repmat`](http://www.mathworks.com/help/matlab/ref/repmat.html) function — Dan, Aug 12 '14 at 12:09
Also, consider skipping creating `B`. Depending on what you want to do with `B`, you may find you can do it with the original `A`, which is smaller. [`bsxfun`](http://www.mathworks.es/es/help/matlab/ref/bsxfun.html) may be handy — Luis Mendo, Aug 12 '14 at 12:11

score 1 · Accepted Answer · answered Aug 12 '14 at 12:13

Many options, the simplest is to use the built in repmat function:

repmat(A, n, 1)

Or you could use linear algebra:

ones(n,1)*A

Or you can use indexing:

A([ones(n,1), ones(n,1)*2])

Or as Luis Mendo points out, you might not even need to replicate it depending on your end goal as linear algebra or bsxfun might prove more efficient solutions.

Fill matrix with values from other, smaller matrix

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