matlabmatrixrowsrepeattiling

Building a matrix by merging the same row vector multiple times

Is there a matlab function which allows me to do the following operation?

x = [1 2 2 3];

and then based on x I want to build the matrix m = [1 2 2 3; 1 2 2 3; 1 2 2 3; 1 2 2 3]

Solution

  • You are looking for the REPMAT function:

    x = [1 2 2 3];
m = repmat(x,4,1);

    You can also use indexing to repeat the rows:

    m = x(ones(4,1),:);

    or even outer-product:

    m = ones(4,1)*x;

    and also using BSXFUN:

    m = bsxfun(@times, x, ones(4,1))