Calculate the remaining index of my data

If i have

   x= 1 2       
      3 4
      2 5
      1 5

is the index of my data. i want to get on remaining of these index but not need index that have i=j i.e [ (1 1) (2 2) (3 3)(4 4)(5 5) and not need fliplr of x i.e [(2 1)(4 3)(5 2)(5 1)]. so i want to the result

   result=
       1 3
       1 4
       2 3
       2 4
       3 5
       4 5

that should not contain fliplr of any index.

[Rik]

It is not clear what your question is. It sounds like you could solve your problem with logical indexing, or even find (and maybe a call to ismember(fliplr(A),A)), but without understanding your problem better I can't help you with actual code.

Answer 1

[the cyclist]

Here is one way.

x= [1 2       
    3 4
    2 5
    1 5];

result = zeros(5*2,2);

ri = 1;
for ii=1:5
    for jj = ii+1:5
        result(ri,:) = [ii jj];
        ri = ri+1;
    end
end

isRowToRemove = ismember(result,x,'rows');

result(isRowToRemove,:) = [];

There is certainly a better way to pre-populate the array result with all possible row values than using the loops, but I got lazy.

[muhammad ismat]

Thank you very much,the cyclist

Answer 2

[OCDER]

%Getting index of an arbitrary matrix
[x, y] = find(ones(5, 'logical'));
x = [x y];

%Remove index i == j
x(x(:,1) == x(:,2), :) = [];

%Get unique x,y and not those that are y,x
x = unique(sort(x, 2), 'rows');

x =
   1     2
   1     3
   1     4
   1     5
   2     3
   2     4
   2     5
   3     4
   3     5
   4     5