Comparing updated array from two consecutive iterations

Hi, I need to create a while loop for a for loop which iterates until the difference between the array c of the current iteration and the array c of the previous iteration is small. Any suggestions on how I could save the updated array for each iteration and then compare the 2 consecutive iterations?

Answer 1

[Stephen23]

Like this:

 prv = 0; % pick first previous value
 for ...
      new = ...
      ...compare prv & new, do whatever
      prv = new;
 end

Answer 2

[Roger Stafford]

Use a while loop that is sure to make at least two trips through.

   old = all NaNs so as to surely fail 1st test 
   b = false;
   while ~b
     new = ...
     b = old and new difference is sufficiently small
     old = new;
   end