help with error in coding

I have a for loop which continually assigns values into a cell array and i keep getting an error. "Subscripted assignment dimension mismatch."

the correct values come up for the first two "m" values but an error shows when its running for "m = 3"

here is the code for that error:

for m = 1:1:3
  for n = 1:1:3
          B = A((A(:,1) - C{2,m}(n,1)).^2 + (A(:,2) - C{2,m}(n,2)).^2 == C{1,m}(1,1)^2,:);
          D{1,m}(n,:) = B;
      end
end

Answer 1

[Iain]

Change D{1,m}(n,:) = B;

To:

D{1,m}{n} = B;