From: SourceForge.net <no...@so...> - 2007-04-26 18:13:41
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Bugs item #1708293, was opened at 2007-04-26 11:13 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1708293&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: Open Resolution: None Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: Wrong solution of system Initial Comment: I was trying to calculate the equation of a hyperbola of the type x^2/a^2 - y^2/b^2 = 1, given two points. Maxima finds, among others, also a wrong solution [a=0,b=0]. (%i4) hyp:x^2/a^2-y^2/b^2=1$ (%i4) eq1:hyp,x=-5/2,y=-3/4$ (%i4) eq2:hyp,x=10/3,y=4/3$ (%i4) solve([eq1,eq2],[a,b]); (%o4) [[a=2,b=-1],[a=-2,b=-1],[a=2,b=1],[a=-2,b=1],[a=0,b=0]] F. Buratti (Italy) bu...@ho... Maxima version: 5.11.99rc2 Maxima build date: 20:46 4/19/2007 host type: i686-pc-mingw32 lisp-implementation-type: GNU Common Lisp (GCL) lisp-implementation-version: GCL 2.6.8 ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1708293&group_id=4933 |
From: SourceForge.net <no...@so...> - 2007-05-01 18:57:38
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Bugs item #1708293, was opened at 2007-04-26 14:13 Message generated for change (Comment added) made by macrakis You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1708293&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 - Solving equations Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: Wrong solution of system Initial Comment: I was trying to calculate the equation of a hyperbola of the type x^2/a^2 - y^2/b^2 = 1, given two points. Maxima finds, among others, also a wrong solution [a=0,b=0]. (%i4) hyp:x^2/a^2-y^2/b^2=1$ (%i4) eq1:hyp,x=-5/2,y=-3/4$ (%i4) eq2:hyp,x=10/3,y=4/3$ (%i4) solve([eq1,eq2],[a,b]); (%o4) [[a=2,b=-1],[a=-2,b=-1],[a=2,b=1],[a=-2,b=1],[a=0,b=0]] F. Buratti (Italy) bu...@ho... Maxima version: 5.11.99rc2 Maxima build date: 20:46 4/19/2007 host type: i686-pc-mingw32 lisp-implementation-type: GNU Common Lisp (GCL) lisp-implementation-version: GCL 2.6.8 ---------------------------------------------------------------------- >Comment By: Stavros Macrakis (macrakis) Date: 2007-05-01 14:57 Message: Logged In: YES user_id=588346 Originator: NO Yes, this is a bug. Here is a simpler example: solve([1/a-1/b=1,a=b],[a,b]) => [[a=0,b=0]] ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1708293&group_id=4933 |