Create a loop which fills numbers 1-7 into matrix until matrix length reached

This is gonna be an easy fix I'm sure. I have a matrix(21,4), and in colum 2 I would like to insert the numbers 1-7 so that they repeat until the end of the column (which is 21 rows long). So I probably need a loop of some sort I'm guessing.

Tried this, which obviously doesn't work:

for rowNumber = 1:21

      for oneToSeven = 1:7

          imageinformation(rowNumber, 2) = oneToSeven;

      end

end

Answer 1

[Andrei Bobrov]

A - your matrix with size <21 x 4 >

A(:,2) = rem((0:size(A,1)-1)',7)+1;

Answer 2

[Matt Fig]

Andrei has shown you a preferred method. However, in answer to your original question, here is one way to solve it with a double loop (as you were attempting to do):

A = zeros(21,4);  % Starting matrix.

for ii = 1:3
    for jj = 1:7
        A((ii-1)*7 + jj,2) = jj;
    end
end