Hi, do you know what is the splus command equivalent to the R command contour(...,method = .flattest.) or contour(..., method = .edge.), thank you very much for your help, best regards... -- Eric J. Alfaro Escuela de Fisica Universidad de Costa Rica 2060-Ciudad Universitaria Rodrigo Facio San Jose, Costa Rica fax: (506) 207-5619, 234-2703 tel: (506) 207-5320, 207-4134, 207-5096 e-mail: ejalfaro at cariari.ucr.ac.cr ealfaro at cosmos.ucr.ac.cr, eric_alfaro at yahoo.com