You can use repmat()
x = [2 0.25 3 1 7];
n_rows = 4;
M = repmat(x, n_rows, 1)
Result
>> M
M =
2.0000 0.2500 3.0000 1.0000 7.0000
2.0000 0.2500 3.0000 1.0000 7.0000
2.0000 0.2500 3.0000 1.0000 7.0000
2.0000 0.2500 3.0000 1.0000 7.0000
Or automatic array expansion
x = [2 0.25 3 1 7];
n_rows = 4;
M = x.*ones(n_rows,1);
Both are equivalent.
