MATLAB: How to make a matrix with all possible combination

MATLABmatrix

Hi everyone!
I would like to make a script that, for number n I can make a matrix M((2*n+1)^2,2).
The entry of this matrix must be all the combinations of n number. For example, for n=2, the matrix would contain:
p=[-2 -2;-2 -1;-2 0; -2 1;-2 2;-1 -2;-1 -1;-1 0;-1 1;-1 2;0 -2;0 -1;0 0;0 1;0 2;1 -2;1 -1;1 0;1 1;1 2;2 -2;2 -1;2 0;2 1;2 2];
I have tried to make a for loop but, instead of getting all the combinations of number, I get the same number repeated five time.
This was the code I was using:
    % code
  n=2; m=n; s=zeros((2*n+1)^2,2);
for i=-n:1:n
    h=[s(:,1)+i,s(:,2)+i]  
end
Thanks.

Best Answer

>> [A,B] = ndgrid(-2:2);
>> [A(:),B(:)]
ans =
  -2  -2
  -1  -2
   0  -2
   1  -2
   2  -2
  -2  -1
  -1  -1
   0  -1
   1  -1
   2  -1
  -2   0
  -1   0
   0   0
   1   0
   2   0
  -2   1
  -1   1
   0   1
   1   1
   2   1
  -2   2
  -1   2
   0   2
   1   2
   2   2
For a general solution, try this:
>> n = 3;
>> C = cell(1,n);
>> [C{:}] = ndgrid(-n:n);
>> C = cellfun(@(m)m(:),C,'uni',0);
>> [C{:}]
ans =
  -3  -3  -3
  -2  -3  -3
  -1  -3  -3
   0  -3  -3
   1  -3  -3
   2  -3  -3
   3  -3  -3
  -3  -2  -3
  -2  -2  -3
  -1  -2  -3
... lots of lines here
   2   2   3
   3   2   3
  -3   3   3
  -2   3   3
  -1   3   3
   0   3   3
   1   3   3
   2   3   3
   3   3   3
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