On Saturday, June 16, 2018 at 12:05:48 PM UTC-7, Robert Dodier wrote: > Hi, > > for the record I've tried this problem with a translation of the > script to pure Maxima and I can't reproduce the error. I'm working > with a recent Maxima build (post-5.41) and ECL 16.1.3 on Linux x86. I > tried it with SBCL 1.4.8 and Clisp 2.49 and those also don't show the > error. > > I think we have a proper maxima error now. It seems to be a bad interaction between "domain:complex" and "assume(...>0)", so it's hard to blame maxima for it, but perhaps a little bit of debugging in maxima allows a fix.
Consider the following script: domain:complex; assume(m1>0,m2>0); A : (-((((-r23^2)+r13^2+r12^2)*(r23^2-r13^2+r12^2))/((m2+m1)*r12^2*r13*r23)+(2*((-r23^2)-r13^2+r12^2))/(m3*r13*r23))^2/(4*((4*(m3+m1))/(m1*m3)-(m2*((-r23^2)+r13^2+r12^2)^2)/(m1*(m2+m1)*r12^2*r13^2))))-(m1*(r23^2-r13^2+r12^2)^2)/(4*m2*(m2+m1)*r12^2*r23^2)+(m3+m2)/(m2*m3); is(equal(A,0)); With: $ sage --maxima ;;; Loading #P"/local-scratch/sage/sage/local/lib/ecl/sb-bsd-sockets.fas" ;;; Loading #P"/local-scratch/sage/sage/local/lib/ecl/sockets.fas" ;;; Loading #P"/local-scratch/sage/sage/local/lib/ecl/defsystem.fas" ;;; Loading #P"/local-scratch/sage/sage/local/lib/ecl/cmp.fas" Maxima 5.39.0 http://maxima.sourceforge.net using Lisp ECL 16.1.2 I get [....] ;;; ;;; Detected access to protected memory, also kwown as 'bus or segmentation fault'. ;;; Jumping to the outermost toplevel prompt ;;; ;;; ;;; Detected access to protected memory, also kwown as 'bus or segmentation fault'. ;;; Jumping to the outermost toplevel prompt ;;; Segmentation fault (core dumped) with $ maxima Maxima 5.41.0 http://maxima.sourceforge.net using Lisp SBCL 1.4.2-1.fc27 I get ... INFO: Binding stack guard page unprotected Binding stack guard page temporarily disabled: proceed with caution Maxima encountered a Lisp error: Binding stack exhausted. PROCEED WITH CAUTION. Automatically continuing. To enable the Lisp debugger set *debugger-hook* to nil. INFO: Binding stack guard page reprotected Both seem consistent with some infinite recursion happening somewhere. > Not sure what might be going on. I didn't try any other Maxima > versions. It's possible that the bug might have been fixed in Maxima, > or in ECL, or that the script I tried isn't exactly the same as the > original so it doesn't trigger the bug. > > I've attached the Maxima script and its output for ECL. > > best, > Robert Dodier > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
