From: SourceForge.net <noreply@so...>  20121031 01:21:23

Bugs item #3577666, was opened at 20121016 08:03 Message generated for change (Comment added) made by rtoy You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3577666&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: Lisp Core  Simplification Group: None >Status: Pending >Resolution: Invalid Priority: 5 Private: No Submitted By: JeanYves (jyoberle) Assigned to: Nobody/Anonymous (nobody) Summary: radcan seems to give nonequvalent function Initial Comment: Hi, When doing radcan((2*x)/(sqrt(1(x^21)^2)*sqrt(1asin(x^21)^2))), the result is 2/(sqrt(2x^2)*sqrt(1asin(x^21))*sqrt(asin(x^21)+1)). But these two expressions are not equivalent. For x = 0.4, (2*x)/(sqrt(1(x^21)^2)*sqrt(1asin(x^21)^2)) gives 20.01585798944382 wheras 2/(sqrt(2x^2)*sqrt(1asin(x^21))*sqrt(asin(x^21)+1)) gives 20.01585798944383. (2*x)/(sqrt(1(x^21)^2)*sqrt(1asin(x^21)^2)) is the result of diff(acos(asin(x^21)),x) if this can help. Build info is build_info("5.28.02","20120827 23:16:48","i686pcmingw32","GNU Common Lisp (GCL)","GCL 2.6.8"). Best regards, JeanYves  >Comment By: Raymond Toy (rtoy) Date: 20121030 18:21 Message: Although the documentation of radcan isn't very clear on this, radcan is expected to produce results like this. I think the idea is if x is very large, then both expressions are equivalent. I think that's true for your expressions. If this is not what you want, use ratsimp or some other combination of expand and factor. Marking as pending/invalid.  Comment By: Valery Lovchikov (lvch) Date: 20121018 23:19 Message: use function factor %i1 factor(sqrt(x^2u*x^4)); %o1 sqrt(1u*x^2)*abs(x) but %i1 radcan(sqrt(x^2u*x^4)); %o1 x*sqrt(1u*x^2)  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3577666&group_id=4933 