looping trough paired examples and compare in conditional statement.

i want to loop trough a data table where I extract the IDs and the values for one attribute time. I want to be able to compare the IDs and compare the attribute values using a conditional statement and then  under certain condition change the valuse of the example and append to a new data table. When I try using the loop for examples that seemed to bring in every example and I had to add on new column as the ID and unfiltered on that column based on the number of iterations.

Why can't I use the value of the loop example is the row number and loop attribute is column number and read the  corresponding cell value inside the two loops?