how to check each value of matrix

let

 a = [1,2,3;4,5,6;7,8,9]
 b = 1
 c = b-a

if an element of 'a' becomes 0 after c operation it should be fixed i.e. on first operation

 c = [0,1,2;3,4,5;6,7,8]

now output should be , 1 of first output should be fixed and

 c = [1,2,3;4,5,6;7,8,9]
 c = [1,1,2;3,4,5;6,7,8]
 c = [1,1,1;2,3,4;5,6,7]
 ............... and so on

Answer 1

[Walter Roberson]

c = a;
while any(c ~= 1)
  c = max(1, c-b)
end

Answer 2

[Stephen23]

Note that you can generate every output of your example in one command, where each row corresponds to one output:

>> toeplitz(ones(1,9),1:9)
ans =
   1   2   3   4   5   6   7   8   9
   1   1   2   3   4   5   6   7   8
   1   1   1   2   3   4   5   6   7
   1   1   1   1   2   3   4   5   6
   1   1   1   1   1   2   3   4   5
   1   1   1   1   1   1   2   3   4
   1   1   1   1   1   1   1   2   3
   1   1   1   1   1   1   1   1   2
   1   1   1   1   1   1   1   1   1