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From: SourceForge.net <noreply@so...>  20091113 23:27:30

Bugs item #2836410, was opened at 20090812 21:07 Message generated for change (Comment added) made by crategus You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2836410&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: Works For Me Priority: 5 Private: No Submitted By: itayperl (itayperl) Assigned to: Nobody/Anonymous (nobody) Summary: won't factor complex polynomials? Initial Comment: I can't get maxima to factor some complex polynomials: (%i1) p1:expand((t+1%i)*(t%i)); (%o1) t^22*%i*t+t%i1 (%i2) p2:expand((t+2%i)*(t+1%i)*(t%i)); (%o2) t^33*%i*t^2+3*t^26*%i*tt%i3 (%i3) factor(p1); (%o3) t^22*%i*t+t%i1 (%i4) factor(p2); (%o4) t^33*%i*t^2+3*t^26*%i*tt%i3 (%i5) factor(solve(p2)); (%o5) [t = ((1)^(1/6)*%i+%i(1)^(1/6))/(1)^(1/6), t = ((1)^(1/6)*%i%i(1)^(1/6))/(1)^(1/6),t = %i1]  >Comment By: Dieter Kaiser (crategus) Date: 20091114 00:27 Message: It is not clear what the desired result should look like. Perhaps the function gfactor does what is needed: (%i17) gfactor(p1); (%o17) (t%i)*(t%i+1) (%i18) gfactor(p2); (%o18) (t%i)*(t%i+1)*(t%i+2) This seems to be not a bug report, but a support request. This might be out of date. Setting the status to pending and the resolution to "works for me". Dieter Kaiser  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2836410&group_id=4933 
From: SourceForge.net <noreply@so...>  20091113 21:50:36

Bugs item #2840634, was opened at 20090820 00:05 Message generated for change (Comment added) made by crategus You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2840634&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: Pending >Resolution: Works For Me Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: CLIENT: Lost socket connection Initial Comment: I have the following file (see attached). Whenever I open wxMaxima and open the file, I get the following error after the line algsys(...) : CLIENT: Lost socket connection ...Restart maxima with 'Maxima>Restart maxima'. Sometimes, after restarting maxima, it manages to automatically continue. This also happens if I introduce the algsys(...) line within maxima (not wxmaxima). I am running ubuntu 9.04  >Comment By: Dieter Kaiser (crategus) Date: 20091113 22:50 Message: I am running Maxima on Ubuntu 9.10. That is the info from the Maxima function build_info(): Maxima version: 5.19post Maxima build date: 20:9 11/13/2009 Host type: i686pclinuxgnu Lisp implementation type: CLISP Lisp implementation version: 2.44.1 (20080223) (built 3436700604) (memory 3467128190) I have no problems with the attached wxm file. There is not enough information to confirm a bug. Changing the status to pending and the resolution to works for me. Dieter Kaiser  Comment By: Robert Dodier (robert_dodier) Date: 20090821 23:04 Message: Hmm. Not observed w/ Maxima 5.19.0 + Windows. What do you see if you try batch("sin_nombre.wxm"); in command line Maxima? What does build_info(); say?  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2840634&group_id=4933 
From: SourceForge.net <noreply@so...>  20091113 20:54:09

Bugs item #2871658, was opened at 20091002 05:01 Message generated for change (Settings changed) made by crategus You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2871658&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: Wont Fix Priority: 5 Private: No Submitted By: dsimcha (dsimcha) Assigned to: Nobody/Anonymous (nobody) Summary: expr, simp=false; : simp=false has no effect. Initial Comment: (%i1) x/x, simp:false; (%o1) 1 (%i2) simp : false; (%o2) false (%i3) x/x; (%o3) x/x (%i4) x/x, simp : true; (%o4) 1 (%i5) x/x; (%o5) x/x  >Comment By: Dieter Kaiser (crategus) Date: 20091113 21:54 Message: A comment about the usage of simp as an evflag has been added to the documentation. Closing this bug report as "Wont fix". Dieter Kaiser  Comment By: Dieter Kaiser (crategus) Date: 20091110 20:07 Message: My last comment on this thread is wrong or at least not complete. The simplification of an expression cannot be suppressed by setting the SIMP flag locally in the routine EV. This is due to the design of Maxima. The SIMP flag as an evflag to the function EV can only suppress the simplification during the evaluation of an expression, but not the simplification which occurs after returning from the evaluation. The calling scheme is: meval > meval1 > simplifya meval1 recursively evaluates and simplifies all arguments of an expression. During this phase the value true or false of the SIMP flag is valid. When meval1 has finished its work, the function simplifya is called again. The expression is simplified, but the value of the SIMP flag is no longer valid. Here another example, when tracing meval, meval1, and simplifya: (%i3) x:sin(1.0),simp:false; 1. Trace: (MEVAL '(($EV) ((MSETQ) $X ((%SIN) 1.0)) ((MSETQ) $SIMP NIL))) 2. Trace: (MEVAL1 '(($EV) ((MSETQ) $X ((%SIN) 1.0)) ((MSETQ) $SIMP NIL))) Evaluate and simplify the argument ((msetq) $simp nil) 3. Trace: (MEVAL 'NIL) 4. Trace: (MEVAL1 'NIL) 4. Trace: MEVAL1 ==> NIL 4. Trace: (SIMPLIFYA 'NIL 'NIL) 4. Trace: SIMPLIFYA ==> NIL 3. Trace: MEVAL ==> NIL 3. Trace: (MEVAL '((MLOCAL))) 4. Trace: (MEVAL1 '((MLOCAL))) 5. Trace: (MEVAL '(($LOCAL))) 6. Trace: (MEVAL1 '(($LOCAL))) 6. Trace: MEVAL1 ==> $DONE 6. Trace: (SIMPLIFYA '$DONE 'NIL) 6. Trace: SIMPLIFYA ==> $DONE 5. Trace: MEVAL ==> $DONE 4. Trace: MEVAL1 ==> $DONE 4. Trace: (SIMPLIFYA '$DONE 'NIL) 4. Trace: SIMPLIFYA ==> $DONE 3. Trace: MEVAL ==> $DONE Evaluate and simplify the argument ((%sin) 1.0). Because the SIMP flag is set to false the result of meval1 is the unsimplified expression ((%sin) 1.0). During the evaluation the simplification is suppressed. Therefore the variable x has an unsimplified expression as its value. 3. Trace: (MEVAL1 '1.0) 3. Trace: MEVAL1 ==> 1.0 3. Trace: (MEVAL1 '((MSETQ) $X ((%SIN) 1.0))) 4. Trace: (SIMPLIFYA '$X 'NIL) 4. Trace: SIMPLIFYA ==> $X 4. Trace: (MEVAL '((%SIN) 1.0)) 5. Trace: (MEVAL1 '((%SIN) 1.0)) 6. Trace: (MEVAL '1.0) 7. Trace: (MEVAL1 '1.0) 7. Trace: MEVAL1 ==> 1.0 7. Trace: (SIMPLIFYA '1.0 'NIL) 7. Trace: SIMPLIFYA ==> 1.0 6. Trace: MEVAL ==> 1.0 5. Trace: MEVAL1 ==> ((%SIN) 1.0) 5. Trace: (SIMPLIFYA '((%SIN) 1.0) 'NIL) 5. Trace: SIMPLIFYA ==> ((%SIN) 1.0) 4. Trace: MEVAL ==> ((%SIN) 1.0) 3. Trace: MEVAL1 ==> ((%SIN) 1.0) 3. Trace: (SIMPLIFYA '((%SIN) 1.0) 'NIL) 3. Trace: SIMPLIFYA ==> ((%SIN) 1.0) 2. Trace: MEVAL1 ==> ((%SIN) 1.0) We have finished the evaluation of meval1. Now the simplifier is called again and the result of meval1 simplifies at this point: 2. Trace: (SIMPLIFYA '((%SIN) 1.0) 'NIL) 3. Trace: (SIMPLIFYA '1.0 'NIL) 3. Trace: SIMPLIFYA ==> 1.0 2. Trace: SIMPLIFYA ==> 0.8414709848078965 1. Trace: MEVAL ==> 0.8414709848078965 The expression simplifies to a numerical result: (%o3) .8414709848078965 But the variable x has an unsimplified value, because the value was assigned during the evaluation phase: (%i5) :lisp $x ((%SIN) 1.0) The only possibility to suppress the simplification is to set the global value of the option variable SIMP to false: (%i6) simp:false; (%o6) false (%i7) x; (%o7) sin(1.0) Therefore, I think we have not a bug, but the expected behaviour of Maximas evaluation and simplification scheme. I think we should add a comment to the documentation about this topic and close this bug report. Dieter Kaiser  Comment By: Dieter Kaiser (crategus) Date: 20091009 19:15 Message: The evaluator and the simplifier do it correct. We can see it at the Lisp level: The output is wrong: (%i1) a:x/x,simp:false; (%o1) 1 But internally the expression is not simplified: (%i2) :lisp $a ((MQUOTIENT) $X $X) Therefore we have to look into the display routines. The expression is again simplified. Dieter Kaiser  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2871658&group_id=4933 
From: SourceForge.net <noreply@so...>  20091113 15:26:39

Bugs item #2880886, was opened at 20091017 02:13 Message generated for change (Comment added) made by dgildea You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2880886&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: Robert Marik (robertmarik) Assigned to: Nobody/Anonymous (nobody) Summary: definite integral  bad answer Initial Comment: This bug has been reported at Sage forum http://groups.google.cz/group/sagedevel/t/c9c147c4dd4ea840 integrate(cos(x)^2 * (1 + sin(x)^2)^3,x,0,%pi/2) returns a value wich is numericaly about 1.4.... but the correct value is close to 0.49 This is my bug_report(), but according to the discussion, the same problem is in the CVS version. Maxima version: 5.18.1 Maxima build date: 13:5 5/3/2009 host type: i686pclinuxgnu lispimplementationtype: CMU Common Lisp lispimplementationversion: CVS 19d 19drelease (19D)  >Comment By: Dan Gildea (dgildea) Date: 20091113 10:26 Message: Fixed in defint.lisp rev 1.67 with a simpler version of the patch below.  Comment By: Dieter Kaiser (crategus) Date: 20091112 10:49 Message: For the record: This bug is related to the bugs: ID: 2890315  integrate(cot(x)^4,x,%pi/6,%pi/2) ID: 2880797  bad answer in integrate(sqrt(sin(t)^2+cos(t)^2),t,0,2*%pi) Again we get wrong poles for an atan expression. The suggested patch in the thread to the bug report ID: 2890315  integrate(cot(x)^4,x,%pi/6,%pi/2) does not help for this examle. Dieter Kaiser  Comment By: Andrej Vodopivec (andrejv) Date: 20091018 09:05 Message: I think the error comes from samesheetsubs (defint.lisp). The function substitutes the limits of integration into expressions which look like atan(something). It substitutes the limits plus it adds contributions from poles of something between the limits. The error is that it also adds contributions from poles on the limits, which I think should be ignored. The patch below fixes this behavior and with the patch applied we get (%i3) integrate(cos(x)^2 * (1 + sin(x)^2)^3,x,0,%pi/2); (%o3) 7*%pi/2^(11/2) (%i4) %, numer; (%o4) 0.485940321361071 Index: defint.lisp =================================================================== RCS file: /cvsroot/maxima/maxima/src/defint.lisp,v retrieving revision 1.66 diff u r1.66 defint.lisp  defint.lisp 6 Sep 2009 13:50:43 0000 1.66 +++ defint.lisp 18 Oct 2009 12:19:35 0000 @@ 938,7 +938,7 @@ ((not (equal (sratsimp ipart) 0)) ()) (t (let ((pole (polesininterval (let (($algebraic t)) (sratsimp (cadr exp)))  var ll ul))) + var ll ul :onboundary nil))) (cond ((and pole (not (or (eq pole '$unknown) (eq pole '$no)))) (do ((l pole (cdr l)) (llist ())) @@ 3259,7 +3259,7 @@ ;;; Returns $no $unknown or a list of poles in the interval (ll ul) ;;; for exp w.r.t. var. ;;; Form of list ((pole . multiplicity) (pole1 . multiplicity) ....) (defun polesininterval (exp var ll ul) +(defun polesininterval (exp var ll ul &key (onboundary t)) (let* ((denom (cond ((mplusp exp) ($denom (sratsimp exp))) ((and (mexptp exp) @@ 3290,7 +3290,7 @@ (t '$no))) (let* ((soltn (caar dummy)) ;; (multiplicity (cdar dummy)) (not used?  cwh)  (rootinllul (ininterval soltn ll ul))) + (rootinllul (ininterval soltn ll ul :onboundary onboundary))) (cond ((eq rootinllul '$no) '$no) ((eq rootinllul '$yes) (let ((limans (isapole exp soltn))) @@ 3365,7 +3365,7 @@ 'epsilon)) 'epsilon 0 '$plus)) (defun ininterval (place ll ul) +(defun ininterval (place ll ul &key (onboundary t)) ;; real values for ll and ul; place can be imaginary. (let ((order (askgreateq ul ll))) (cond ((eq order '$yes)) @@ 3374,8 +3374,8 @@ (list '(mlist simp) ll ul))))) (if (not (equal ($imagpart place) 0)) '$no  (let ((lessequl (askgreateq ul place))  (greateqll (askgreateq place ll))) + (let ((lessequl (askgreateq ul place :onboundary onboundary)) + (greateqll (askgreateq place ll :onboundary onboundary))) (if (and (eq lessequl '$yes) (eq greateqll '$yes)) '$yes '$no)))) (defun realroots (exp var) @@ 3401,7 +3401,7 @@ (cadr dummy)) rootlist))))))))))) (defun askgreateq (x y) +(defun askgreateq (x y &key (onboundary t)) ;;; Is x > y. X or Y can be $MINF or $INF, zeroA or zeroB. (let ((x (cond ((among 'zeroa x) (subst 0 'zeroa x)) @@ 3432,8 +3432,10 @@ ((eq y '$minf) '$yes) (t (let ((ans ($asksign (m+ x (m y)))))  (cond ((member ans '($zero $pos) :test #'eq) + (cond ((eq ans '$pos) '$yes) + ((eq ans '$zero) + (if onboundary '$yes '$no)) ((eq ans '$neg) '$no) (t '$unknown)))))))  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2880886&group_id=4933 
From: SourceForge.net <noreply@so...>  20091113 15:25:02

Bugs item #2890315, was opened at 20091101 10:54 Message generated for change (Comment added) made by dgildea You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2890315&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  Integration Group: None >Status: Closed >Resolution: Fixed Priority: 5 Private: No Submitted By: mitreuden (mitreude) Assigned to: Nobody/Anonymous (nobody) Summary: integrate(cot(x)^4,x,%pi/6,%pi/2) answer Initial Comment: The first time integrate(cot(x)^4,x,%pi/6,%pi/2) is executed, the answer of %pi/3 returned is correct. However, when the integral is computed again, an incorrect answer of 4*%pi/3 is returned.  >Comment By: Dan Gildea (dgildea) Date: 20091113 10:25 Message: Fixed in defint.lisp rev 1.67 with a simpler version of the patch below *** defint.lisp.~1.66.~ Fri Nov 13 10:09:07 2009  defint.lisp Fri Nov 13 10:09:25 2009 *************** *** 944,950 **** (do ((l pole (cdr l)) (llist ())) ((null l) llist) (cond ! ((eq (caar l) ll) t) ;Skip this one by definition. (t (let ((lowlim ($limit (cadr exp) var (caar l) '$minus)) (uplim ($limit (cadr exp) var (caar l) '$plus))) (cond ((and (not (eq lowlim uplim))  944,951  (do ((l pole (cdr l)) (llist ())) ((null l) llist) (cond ! ((zerop1 (m (caar l) ll)) t) ; don't worry about discontinuity ! ((zerop1 (m (caar l) ul)) t) ; at boundary of integration (t (let ((lowlim ($limit (cadr exp) var (caar l) '$minus)) (uplim ($limit (cadr exp) var (caar l) '$plus))) (cond ((and (not (eq lowlim uplim))  Comment By: Dieter Kaiser (crategus) Date: 20091112 10:36 Message: I think the routine atanpoles does not work correctly for expressions like atan(tan(x)). It does not take into account the cases where we have more than one pole in the interval and it add extra poles which are not present. With triginverses set to ALL these bugs in atanpoles do not occur, because atan(tan(x)) is always simplified to x. The routine atanpoles therefore is never called. This error in atanpoles is responsible for both bugs: ID: 2890315  integrate(cot(x)^4,x,%pi/6,%pi/2) ID: 2880797  bad answer in integrate(sqrt(sin(t)^2+cos(t)^2),t,0,2*%pi) I have no idea what can be done in the routine atanpoles, but we can add a test in the routine intsubs. We simplify look for a atan(tan(x)) expression, simplify it and call limitsubs to go on: (t (setq rpart (sratsimp rpart)) (cond ((limitsubs rpart a b)) > ((eq (caar (cadr rpart)) '%tan) > ;; We have atan(tan(x)). We simplify it to x. > (limitsubs (cadr (cadr rpart)) a b)) (t (samesheetsubs rpart a b))))))))) With this extension we avoid to set the flag $triginverses. All works fine. The testsuite has no problems and the reported examples are correct: (%i5) integrate(sin(x)^2+cos(x)^2,x,0,2*%pi); (%o5) 2*%pi (%i6) integrate(cot(x)^4,x,%pi/6,%pi/2); (%o6) %pi/3 Remark: It does not help to avoid the usage of trigsimp in the routine samesheetsubs. I have replaced the call with the following function: (defun substtansin/cos (expr) (let (old new) (cond ((not (setq old (isinop expr '%tan))) expr) (t (let* ((arg (cadr old)) (new (div (simplify (list '(%sin) arg)) (simplify (list '(%cos) arg))))) (setq expr (maximasubstitute new old expr))) (substtansin/cos expr))))) This is the change in the function samesheetsubs: (defun samesheetsubs (exp ll ul &aux ans) (let* (;(exp (mfuncall '$trigsimp exp)) > (exp (substtansin/cos exp)) (poles (atanpoles exp ll ul))) With this replacement I always get wrong result for the integral integrate(cot(x)^4,x,%pi/6,%pi/2). This way I found that we have no problem with trigsimp, but with atanpoles. Dieter Kaiser  Comment By: Raymond Toy (rtoy) Date: 20091109 10:19 Message: Some simple tests show that just applying the rule tan(a)=sin(a)/cos(a) in samesheetsubs is enough to fix this problem. I do not know why running trigsimp itself causes problems or why, as mitreude says, changing the order of the rules in trgsmp makes it work. Especially in this case since the expression is atan(tan(x+%pi/6)).  Comment By: Raymond Toy (rtoy) Date: 20091106 11:45 Message: Just to note that trgsmp gets loaded because samesheetsubs (in defint.lisp) calls trigsimp. The whole purpose (based on the comments) is to convert tan to sin/cos. Also, on the first integrate, samesheetsubs is called just once on atan(tan(x+%pi/6)) for x=0,%pi/3, and returns 4*%pi/3. On the second integration, samesheetsubs is called twice with the same arguments and same results. Have not figured out anything more.  Comment By: mitreuden (mitreude) Date: 20091104 15:45 Message: OK, I examined the file trgsmp.mac and found that if I changed the order of simplification rules in the definition of the function trigsimp(),I can consistently get the correct answer. Here is what I did: load(trgsmp)$ defrule(trigrule1,sec(a),1/cos(a))$ defrule(trigrule2,csc(a),1/sin(a))$ defrule(trigrule3,tan(a),sin(a)/cos(a))$ defrule(trigrule4,cot(a),cos(a)/sin(a))$ defrule(htrigrule1,sech(a),1/cosh(a))$ defrule(htrigrule2,csch(a),1/sinh(a))$ defrule(htrigrule3,tanh(a),sinh(a)/cosh(a))$ defrule(htrigrule4,coth(a),cosh(a)/sinh(a))$ trigsimp(x):=trigsimp3(ratsimp(apply1(x,trigrule4,trigrule1,trigrule2,trigrule3,trigrule4, htrigrule1,htrigrule2,htrigrule3,htrigrule4)))$ integrate(cot(x)^4,x,%pi/6,%pi/2); It seems that the tangent simplification should not come first. Why this works on this particular problem, I don't have a clue. Also, might changing the simplification order cause a problem in an integral where Maxima previously found the correct answer? I have more questions than answers. Mike Treuden  Comment By: Raymond Toy (rtoy) Date: 20091104 12:01 Message: Sorry, you are correct. My working tree had a fix for Bug 2880797. Why this makes a difference, I don't know.  Comment By: Dieter Kaiser (crategus) Date: 20091103 17:21 Message: I can see this bug too with CLISP 2.44 and Maxima 5.19post on my Linux system: (%i2) integrate(cot(x)^4,x,%pi/6,%pi/2); (%o2) %pi/3 (%i3) integrate(cot(x)^4,x,%pi/6,%pi/2); (%o3) 4*%pi/3 Evaluating this integral the package trgsmp is loaded: (%i5) functions; (%o5) [trigonometricp(exp),trigsimp(x),trigsimp3(expn),trigsimp1(expn), improve(expn,subsofar,listoftrigsq),listoftrigsq(expn), specialunion(list1,list2),update(form,complement),expnlength(expr), argslength(args)] When I kill the functions defined by this package the integral is correct again: (%i6) kill(functions); (%o6) done (%i7) integrate(cot(x)^4,x,%pi/6,%pi/2); (%o7) %pi/3 And the next evaluation is wrong again: (%i8) integrate(cot(x)^4,x,%pi/6,%pi/2); (%o8) 4*%pi/3 When I preload the package trgsmp I get the error immediately: (%i11) kill(functions); (%o11) done (%i12) load(trgsmp); (%o12) "/usr/local/share/maxima/5.19post/share/trigonometry/trgsmp.mac" (%i13) integrate(cot(x)^4,x,%pi/6,%pi/2); (%o13) 4*%pi/3 Reopening the bug report. Dieter Kaiser  Comment By: Raymond Toy (rtoy) Date: 20091102 11:25 Message: Neat bug. But current cvs returns %pi/3 both times. Do not know what has changed, but it seems current CVS has fixed this issue. Marking as pending/worksforme  Comment By: mitreuden (mitreude) Date: 20091101 22:46 Message: This problem occurs with version 5.19.2 of Maxima.  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=2890315&group_id=4933 