Getting rid of zeros in matrix

I need to find solutions to right triangles when I run my code I get the answers but it is separated by rows of all zeros like this:

     0     0     0
     0     0     0
     0     0     0
     0     0     0
     3     4     5
     0     0     0
     0     0     0
     0     0     0
     0     0     0
     6     8    10
     0     0     0
     0     0     0
     5    12    13

and so on. Here is my code:

for a=1:50;
  for b=a:50;
      c=sqrt(a^2+b^2);
      if c<=50 && c==floor(c)
          matrix=[a,b,c];
          mat(c,:)=matrix

        end
    end
end
mat

Any suggestions on how to fix this? Thank you! :)

Answer 1

[Jan]

index = 0;
for a=1:50;
  for b=a:50;
    c = sqrt(a^2+b^2);
    if c<=50 && c==floor(c)
        index = index + 1;
        mat(index,:)=[a,b,c];
      end
  end
end

[Katrina]

Thank you!!