Thank you for your response. My explanation of the problem was
incomplete. I had hoped that excel had a program that would plot stair
steps.

My problem is illustrated by the following example. Z can have any
length, but its entries are always 0 or 1. (X,Y) are the coordinates of
points in a scatter plot.

Z X Y
0 1 0
1 2 0
0 2 1
1 3 1
4 1
4 2

Can excel compute X and Y for any given Z?

John Adams
Bethlehem, PA