mat ops to locate values and place into new matrix

column width should be length of longest row of 9s. I can do this by loops and placing the values into a preallocated zeroes matrix but its slow. The actual matrix is very very large.

 if true
   a = [1 9 3 5 2 7;
        9 9 9 9 1 2;
        6 5 0 3 9 9;
        6 2 1 7 8 7;  
        4 9 9 9 9 9]
out =  [9 0 0 0 0 0;
        9 9 9 9 0 0;
        9 9 0 0 0 0;
        0 0 0 0 0 0;
        9 9 9 9 9 0] 
  end

Answer 1

[Jos (10584)]

b = sort(a.*(a==9), 2, 'descend')