Repeating one loop without adding data to the array

Hi all,

I've got a for-loop that randomises the '1's in one of the columns in a 10-by-6 matrix each of 6 loops. In another function I have a measure for nestedness of the matrix (nestedloop2), which can be somewhere from 1-to-100. I check nestedness before randomising the ones in a column, and after (oldnest vs. newnest).

The problem I have is that I only want the for-loop to continue if nestedness decreases. In other words, I only want to add 'newnest' to the 'nest'-array if 'newnest < oldnest'. I have tried using an if-statement or a while-loop, but I'm doing something wrong. Script:

for i=1:6;

    oldnest=nestedloop2(H)
    COLNOW=find(COL==i);
    ii=H(:,COLNOW);
    ii(randperm(10))=ii;
    H(:,COLNOW)=ii;
    newnest=nestedloop2(H)
    nest=[nest,newnest];

end

I hope my description is a bit clear. Thanks in forward.

Cheers, T.

Answer 1

[Matt Fig]

From your description, you only want the variable 'nest' to grow and the FOR loop to continue if newnest is less than oldnest.

for i=1:6;
    oldnest=nestedloop2(H)
    COLNOW=find(COL==i);
    ii=H(:,COLNOW);
    ii(randperm(10))=ii;
    H(:,COLNOW)=ii;
    newnest=nestedloop2(H)

      if newnest<oldnest
      nest=[nest,newnest];
      else
      break
      end
  end

[Tim]

Thanks, but I might have formulated it incorrectly then.

I just want the loop to repeat the same 'i' (if 'newnest >= oldnest'), without adding to the array, until 'newnest<oldnest'.

[Matt Fig]

Then you do not want a FOR loop.

cnt = 1;
while cnt<=6
  oldnest=nestedloop2(H)
  COLNOW=find(COL==cnt);
  ii=H(:,COLNOW);
  ii(randperm(10))=ii;
  H(:,COLNOW)=ii;
  newnest=nestedloop2(H)

      if newnest<oldnest
         nest=[nest,newnest];
         cnt = cnt + 1;
      end
end

[Tim]

Thanks!