## maxima-bugs

 [Maxima-bugs] [ maxima-Bugs-2604950 ] rats with keepfloat From: SourceForge.net - 2009-02-21 20:52:34 ```Bugs item #2604950, was opened at 2009-02-16 04:50 Message generated for change (Comment added) made by dgildea You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2604950&group_id=4933 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None >Status: Closed >Resolution: Fixed Priority: 5 Private: No Submitted By: stan (schymans) >Assigned to: Dan Gildea (dgildea) >Summary: rats with keepfloat Initial Comment: Dear all, This is a bug detected using maxima through SAGE: sage: sage: var('a b c') (a, b, c) sage: ((a*b - 0.5*a*(b - c))/a).simplify_radical() 0 Here is what Robert Dodier wrote about this (http://groups.google.com/group/sage-devel/browse_thread/thread/5613095ef16c9ead/d67dfbb9b8465397?lnk=gst&q=radcan#d67dfbb9b8465397): I guess Sage has keepfloat=true somewhere. That seems to trigger a bug in Maxima. (%i7) radcan ((a*b - 0.5*a*(b - c))/a), keepfloat=true; (%o7) 0 (%i8) radcan ((a*b - 0.5*a*(b - c))/a), keepfloat=false; `rat' replaced -0.5 by -1/2 = -0.5 (%o8) (c+b)/2 In any case, the simplification yielding 0 is a clearly undesired behaviour, so it would be great if the simplify code could be changed to deal with floats. Thanks! ---------------------------------------------------------------------- >Comment By: Dan Gildea (dgildea) Date: 2009-02-21 15:52 Message: src/rat3a.lisp rev 1.17: o cquotient: use / rather than truncate bug introduced by replacing quotient -> truncate in rat3a.lisp rev 1.9 ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2604950&group_id=4933 ```