From: SourceForge.net <noreply@so...>  20070324 11:06:17

Bugs item #1685361, was opened at 20070321 11:48 Message generated for change (Comment added) made by willisbl You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1685361&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 Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Stavros Macrakis (macrakis) Assigned to: Nobody/Anonymous (nobody) Summary: inverse of matrix with taylorexprs wrong Initial Comment: matrix([ 1, taylor(x,x,0,1)], [taylor(y,y,0,1), 1 ]) ^^ 1 => matrix([ 1/(y^21) , y/(y^21) ], [ y/(y^21) , 1/(y^21) ]) which is very wrong (it has apparently conflated variables x and y  depending on the previous session history, it may return a result in x or in y). This happens both with ratmx=false and ratmx=true. To calculate the correct answer: subst([a=taylor(x,x,0,1),b=taylor(y,y,0,1)], matrix([1,a],[b,1])^^1 ) => matrix([1+x*y+...,x+...],[y+...,1+x*y+...]) Not sure whether this is a problem in the matrix code or the taylor code.  >Comment By: Barton Willis (willisbl) Date: 20070324 06:06 Message: Logged In: YES user_id=895922 Originator: NO A related bug is 939022.  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1685361&group_id=4933 