How to get image for each and every iteration?

I need to demonstrate arnold's cat map.

if true
  % code
while t<T2
  for i= 1 : rows
    for j= 1 : columns
      r = mod(i+j,N)+1;
      c = mod(i+(2*j)+1,N)+1;
       *imscram(i,j)=iscram(r,c);*
    end
  end
end

In this imscram(i,j)=iscram(r,c);, I would like to capture image for each and every iteration.I tried with imwrite function.But its not working.

[Image Analyst]

If your image has a megapixel, surely you don't want to save a million image files onto disk with the current state of the image you're building up.

Answer 1

[Image Analyst]

See my attached Arnold's cat map demo: