Hi All, first - I am using Athena 0.8.054 under Windows XP and Adam 0.8.057 under Linux We have checked this problem at 2 computers. I played a little bit with Analysis function - Difference Spectra - norm(E) It works fine when I work with one group - it plots spectrum, difference and program computes the difference and the integral. Now, I want to do the same for marked groups - it computes and makes as new groups the difference spectra. If I want to compute also integrals for marked groups program does not execute operation. Simply it does nothing, or tries to do something with the first marked group, but without result. the error message from shell window is like that: for Athena 0.8.057 Linux: Tk::Error: Can't upgrade that kind of scalar at /usr/bin/athena line 12950. main::diff_marked at /usr/bin/athena line 12950 main::__ANON__ at /usr/bin/athena line 12614 Tk callback for .frame1.frame1.frame2.button Tk::__ANON__ at /usr/lib/perl5/vendor_perl/5.8.8/i386-linux-thread-multi/Tk.pm line 250 Tk::Button::butUp at /usr/lib/perl5/vendor_perl/5.8.8/i386-linux-thread-multi/Tk/Button.pm line 175 <ButtonRelease-1> (command bound to event) and for Athena 0.8.054 Windows Tk::Error: Can't upgrade that kind of scalar at athena line 12863. main::diff_marked at athena line 12863 main::__ANON__ at athena line 12527 Tk callback for .frame1.frame2.frame2.button Tk::__ANON__ at /PerlApp/Tk.pm line 252 Tk::Button::butUp at /PerlApp/Tk/Button.pm line 111 <ButtonRelease-1> (command bound to event) cheers darek and adam ------------------------------------------------------------------------ dr. Zajac Dariusz A. Deutsches Elektronen-Synchrotron -Hasylab phone: +49-40-8998-2932 Notkestr. 85 fax: +49-40-8998-2787 22607 Hamburg e-mail: dariusz.zajac@desy.de Germany ------------------------------------------------------------------------