Iterate through matrix until no more possible calculations.

I have an array that shortens up every time i do an iteration. But how do i know when there are no more possible calculations to be done and the size of the array cannot be shortened up any more. i'm thinking using while loop but don't know how to check it. Any help please.

Suppose i have a matrix

a=[1,2; 
   1,3;
   1,4;
   2,12;
   2,15;
   5,7;
   5,8;
   6,98;
   6,99;
   7,8;
   7,9;
   7,11;
   9,14;
   9,16;
   12,18;
   14,20;
   20,35;
   98,102;
   99,204;
  204,300;
  301,305;
  308,400];

every time i do an iteration i remove the elements of one of the arrays below. first

b=[1,2,3,4,12,15,18],

then

c=[5,7,8,9,14,16,20,35],

then

d=[6,98,99,102,204,300] and i'm left with 

a=[301,305;308,400].

So how do i know there are no more iterations to go?

Answer 1

[Thorsten]

Store the b, c, d arrays as cell elements in cell b. Then insert the i'th row of a into anew if its not element of any list in b.

anew = [];
for i = 2:size(a, 1)
  bi = 1;
  while bi <= numel(b) && isempty(intersect(a(i,:), b{bi}))
    bi = bi + 1;
  end
  if bi > numel(b) % a(i,:) not member of any b{bi}
    anew(end+1,:) = a(i,:);
  end
end

disp('anew')
disp(anew)