Raul,
I tried using the 2 Essays together. But I think I did not work hard enough at them. I think there are some steps not shown, but I can likely get them. In particular, the second tree on the page seems to have tree nodes labeled with their index, their contribution and their accumulation. I guess some hidden steps paste together the three items for each node. It's not worth working about any further. Thank you for your help, ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
