Repeat vectors within a matrix multiple times

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Hi, I am looking for an efficient approach (without a for loop) to repeat a vector multiple times within a matrix.
For e.g. x = [1 2; 3 4; 5 6]
I want to repeat each row n times:
if n = 2: x = [1 2; 1 2; 3 4; 3 4; 5 6; 5 6]. The important point is that the repeated rows should be together.
I was thinking of using repmat, but that allows me to repeat the matrix and not vectors within the matrix..as far as I know, any help would be great!

Answers (3)

Azzi Abdelmalek
Azzi Abdelmalek on 14 Jul 2013
Edited: Azzi Abdelmalek on 14 Jul 2013
n=3
out=reshape(repmat(x',n,1),size(x,2),[])'

Andrei Bobrov
Andrei Bobrov on 14 Jul 2013
Edited: Andrei Bobrov on 14 Jul 2013
x(ones(n,1)*(1:size(x,1)),:);
or
x(kron(1:size(x,1),ones(1,n)),:);

Jan
Jan on 14 Jul 2013
Edited: Jan on 14 Jul 2013
n = 2;
kron(x, ones(n, 1))

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