MATLAB: Counting up starting from first row of zeros in a matrix, then 1’s.

binarycountingforfor loopifif statementmatrixrowssimplezeros

This should be relatively easy.
Given a binary matrix, i want to start counting up (starting at 1) at the first zero until the last zero. Then i want to continue counting from the top row at the first 1. Like so:
[0 1 0;1 1 0;0 0 1] becomes [1 6 2;7 8 3; 4 5 9]
Prefereably with an If and/or for statement, but im open to solutions.

Best Answer

>> a = [1,6,2;7,8,3;4,5,9] % what you want
a =
   1   6   2
   7   8   3
   4   5   9
>> m = [0,1,0;1,1,0;0,0,1]
m =
   0   1   0
   1   1   0
   0   0   1
Method one:
>> v = reshape(m.',1,[]);
>> [~,b] = sort(v);
>> [~,b] = sort(b);
>> b = reshape(b,size(m,2),[]).'
b =
   1   6   2
   7   8   3
   4   5   9
Method two:
>> b = m.';
>> v = reshape(b,1,[]);
>> [~,x] = sort(v);
>> b(x) = 1:numel(m);
>> b = b.'
b =
   1   6   2
   7   8   3
   4   5   9
Note that these will work for any number of values, not just binary matrices.
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