http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume en-us 2026 Maplesoft, A Division of Waterloo Maple Inc. Maplesoft Document System Fri, 12 Jun 2026 14:50:36 GMT Fri, 12 Jun 2026 14:50:36 GMT The latest comments added to the Post, Surprise behavior with assume http://www.mapleprimes.com/images/mapleprimeswhite.jpg http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume?ref=Feed:MaplePrimes:Surprise behavior with assume:Comments#comment80655 The procedure <code>assume</code> assigns a local variable named (say) <code>a~</code> to the global variable <code>a</code>. However, the assignment statement does not evaluate its left-side symbol (for good reason), so following the assignment statement, the global <code>a</code> is assigned 0 (etc). However, the Matrix A has the local variable <code>a~</code>, so there is no effect on it. To assign values to the assumed variables you could replace the line <code>a:=0; b:=1/2; c:=0</code> with <code>assume(a=0,b=1/2,c=0)</code>. That works because, unlike the assignment statement, the procedure <code>assume</code> evaluates the variables. The latest comments added to the Post, Surprise behavior with assume 80655 Sun, 28 Aug 2005 01:27:01 Z Joe Riel Joe Riel http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume?ref=Feed:MaplePrimes:Surprise behavior with assume:Comments#comment86858 Thanks, Joe Riel. I understand better what is happening. This led me to think of with(RealDomain), but this did not do the trick. Somehow, I don't remember now how I came to it, I found that the following is just what I want. > restart: > with(LinearAlgebra): > A:=Matrix([[a,b],[b,c]]); > BilinearForm(Vector([x,y]),Vector([u,v]),A,conjugate=false): > expand(%); Your suggest let to this better idea. It is better in ways to complicated to explain here. However, see five lines from the bottom of page 302 in the Maple Conference 2005 Proceedings. The latest comments added to the Post, Surprise behavior with assume 86858 Sun, 28 Aug 2005 03:10:01 Z jherod jherod http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume?ref=Feed:MaplePrimes:Surprise behavior with assume:Comments#comment86850 It should be <code>assign(a=0,b=1/2,c=0)</code> because <code>assign</code> evaluates the variables. The latest comments added to the Post, Surprise behavior with assume 86850 Tue, 30 Aug 2005 09:38:42 Z alec alec http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume?ref=Feed:MaplePrimes:Surprise behavior with assume:Comments#comment90231 Thanks, alec. At least I knew what I meant 8-). The latest comments added to the Post, Surprise behavior with assume 90231 Tue, 30 Aug 2005 17:42:47 Z Joe Riel Joe Riel http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume?ref=Feed:MaplePrimes:Surprise behavior with assume:Comments#comment90232 I just noticed that yesterday - I din't notice that when I read that first time. That's another example when comment editing possibility would be very helpful. The latest comments added to the Post, Surprise behavior with assume 90232 Tue, 30 Aug 2005 17:47:56 Z Alec Mihailovs Alec Mihailovs http://www.mapleprimes.com/posts/43670-Surprise-Behavior-With-Assume?ref=Feed:MaplePrimes:Surprise behavior with assume:Comments#comment90233 if you hadn't replied 8-). My preference would be to allow edits regardless whether there is a response. At least that way comments could get corrected at the source, rather than in the responses. The thorough poster would mention that the comment had been changed as a result of the following feedback. The latest comments added to the Post, Surprise behavior with assume 90233 Tue, 30 Aug 2005 18:07:54 Z Joe Riel Joe Riel