## [Maxima-bugs] [ maxima-Bugs-1629723 ] bug in limit, asks sign of IND, encountered in integrator

 [Maxima-bugs] [ maxima-Bugs-1629723 ] bug in limit, asks sign of IND, encountered in integrator From: SourceForge.net - 2007-09-22 14:56:10 ```Bugs item #1629723, was opened at 2007-01-07 01:15 Message generated for change (Comment added) made by rtoy You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&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 - Limit Group: None >Status: Open >Resolution: None Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: bug in limit, asks sign of IND, encountered in integrator Initial Comment: quoted from the mailing list: On 12/11/06, Daniel Lakeland wrote: >integrate(abs(sin(x)/x),x,0,inf) asks the seemingly stupid question: >Is ind positive, negative, or zero? > >the user has absolutely no idea what maxima is asking... I'm going to >assume that it has something to do with a change of variable deep >within the integrator... but it's completely opaque to me. This is definitely a bug, and should be reported. Integrate is calling limit, and the bug is actually in the limit routine: limit( abs(sin(x))/x , x , inf) => asks sign of ind IND is supposed to be used by Limit as a return value meaning that the limit set is bounded, e.g. limit(sin(x),x,inf) => ind, but obviously here it's gotten its wires crossed. I suggest you write up the limit bug with a note that definite integration encounters it. ---------------------------------------------------------------------- >Comment By: Raymond Toy (rtoy) Date: 2007-09-22 10:56 Message: Logged In: YES user_id=28849 Originator: NO Why is limit(abs(sin(x))/x, x, inf) ind? Shouldn't it be zero? abs(sin(x))/x is surely bounded between 0 and 1/x. Am I missing something? Reopening. ---------------------------------------------------------------------- Comment By: Dan Gildea (dgildea) Date: 2007-09-22 10:47 Message: Logged In: YES user_id=1797506 Originator: NO Fixed in limit.lisp rev 1.40. (%i3) limit( abs(sin(x))/x , x , inf) ; (%o3) ind ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&group_id=4933 ```

 [Maxima-bugs] [ maxima-Bugs-1629723 ] bug in limit, asks sign of IND, encountered in integrator From: SourceForge.net - 2007-01-07 06:15:59 ```Bugs item #1629723, was opened at 2007-01-06 22:15 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=1629723&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 - Limit Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: bug in limit, asks sign of IND, encountered in integrator Initial Comment: quoted from the mailing list: On 12/11/06, Daniel Lakeland wrote: >integrate(abs(sin(x)/x),x,0,inf) asks the seemingly stupid question: >Is ind positive, negative, or zero? > >the user has absolutely no idea what maxima is asking... I'm going to >assume that it has something to do with a change of variable deep >within the integrator... but it's completely opaque to me. This is definitely a bug, and should be reported. Integrate is calling limit, and the bug is actually in the limit routine: limit( abs(sin(x))/x , x , inf) => asks sign of ind IND is supposed to be used by Limit as a return value meaning that the limit set is bounded, e.g. limit(sin(x),x,inf) => ind, but obviously here it's gotten its wires crossed. I suggest you write up the limit bug with a note that definite integration encounters it. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&group_id=4933 ```
 [Maxima-bugs] [ maxima-Bugs-1629723 ] bug in limit, asks sign of IND, encountered in integrator From: SourceForge.net - 2007-09-22 14:47:38 ```Bugs item #1629723, was opened at 2007-01-07 01:15 Message generated for change (Comment added) made by dgildea You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&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 - Limit Group: None >Status: Closed >Resolution: Fixed Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: bug in limit, asks sign of IND, encountered in integrator Initial Comment: quoted from the mailing list: On 12/11/06, Daniel Lakeland wrote: >integrate(abs(sin(x)/x),x,0,inf) asks the seemingly stupid question: >Is ind positive, negative, or zero? > >the user has absolutely no idea what maxima is asking... I'm going to >assume that it has something to do with a change of variable deep >within the integrator... but it's completely opaque to me. This is definitely a bug, and should be reported. Integrate is calling limit, and the bug is actually in the limit routine: limit( abs(sin(x))/x , x , inf) => asks sign of ind IND is supposed to be used by Limit as a return value meaning that the limit set is bounded, e.g. limit(sin(x),x,inf) => ind, but obviously here it's gotten its wires crossed. I suggest you write up the limit bug with a note that definite integration encounters it. ---------------------------------------------------------------------- >Comment By: Dan Gildea (dgildea) Date: 2007-09-22 10:47 Message: Logged In: YES user_id=1797506 Originator: NO Fixed in limit.lisp rev 1.40. (%i3) limit( abs(sin(x))/x , x , inf) ; (%o3) ind ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&group_id=4933 ```
 [Maxima-bugs] [ maxima-Bugs-1629723 ] bug in limit, asks sign of IND, encountered in integrator From: SourceForge.net - 2007-09-22 14:56:10 ```Bugs item #1629723, was opened at 2007-01-07 01:15 Message generated for change (Comment added) made by rtoy You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&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 - Limit Group: None >Status: Open >Resolution: None Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: bug in limit, asks sign of IND, encountered in integrator Initial Comment: quoted from the mailing list: On 12/11/06, Daniel Lakeland wrote: >integrate(abs(sin(x)/x),x,0,inf) asks the seemingly stupid question: >Is ind positive, negative, or zero? > >the user has absolutely no idea what maxima is asking... I'm going to >assume that it has something to do with a change of variable deep >within the integrator... but it's completely opaque to me. This is definitely a bug, and should be reported. Integrate is calling limit, and the bug is actually in the limit routine: limit( abs(sin(x))/x , x , inf) => asks sign of ind IND is supposed to be used by Limit as a return value meaning that the limit set is bounded, e.g. limit(sin(x),x,inf) => ind, but obviously here it's gotten its wires crossed. I suggest you write up the limit bug with a note that definite integration encounters it. ---------------------------------------------------------------------- >Comment By: Raymond Toy (rtoy) Date: 2007-09-22 10:56 Message: Logged In: YES user_id=28849 Originator: NO Why is limit(abs(sin(x))/x, x, inf) ind? Shouldn't it be zero? abs(sin(x))/x is surely bounded between 0 and 1/x. Am I missing something? Reopening. ---------------------------------------------------------------------- Comment By: Dan Gildea (dgildea) Date: 2007-09-22 10:47 Message: Logged In: YES user_id=1797506 Originator: NO Fixed in limit.lisp rev 1.40. (%i3) limit( abs(sin(x))/x , x , inf) ; (%o3) ind ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&group_id=4933 ```
 [Maxima-bugs] [ maxima-Bugs-1629723 ] bug in limit, asks sign of IND, encountered in integrator From: SourceForge.net - 2007-09-22 16:49:55 ```Bugs item #1629723, was opened at 2007-01-07 01:15 Message generated for change (Comment added) made by dgildea You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&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 - Limit Group: None >Status: Closed >Resolution: Fixed Priority: 5 Private: No Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: bug in limit, asks sign of IND, encountered in integrator Initial Comment: quoted from the mailing list: On 12/11/06, Daniel Lakeland wrote: >integrate(abs(sin(x)/x),x,0,inf) asks the seemingly stupid question: >Is ind positive, negative, or zero? > >the user has absolutely no idea what maxima is asking... I'm going to >assume that it has something to do with a change of variable deep >within the integrator... but it's completely opaque to me. This is definitely a bug, and should be reported. Integrate is calling limit, and the bug is actually in the limit routine: limit( abs(sin(x))/x , x , inf) => asks sign of ind IND is supposed to be used by Limit as a return value meaning that the limit set is bounded, e.g. limit(sin(x),x,inf) => ind, but obviously here it's gotten its wires crossed. I suggest you write up the limit bug with a note that definite integration encounters it. ---------------------------------------------------------------------- >Comment By: Dan Gildea (dgildea) Date: 2007-09-22 12:49 Message: Logged In: YES user_id=1797506 Originator: NO oops, sorry. in limit.lisp rev 1.41: limit(abs(sin(x))/x, x, inf) => 0 however: limit(abs(sin(x))/sin(x), x, inf) => 1 still not correct ---------------------------------------------------------------------- Comment By: Raymond Toy (rtoy) Date: 2007-09-22 10:56 Message: Logged In: YES user_id=28849 Originator: NO Why is limit(abs(sin(x))/x, x, inf) ind? Shouldn't it be zero? abs(sin(x))/x is surely bounded between 0 and 1/x. Am I missing something? Reopening. ---------------------------------------------------------------------- Comment By: Dan Gildea (dgildea) Date: 2007-09-22 10:47 Message: Logged In: YES user_id=1797506 Originator: NO Fixed in limit.lisp rev 1.40. (%i3) limit( abs(sin(x))/x , x , inf) ; (%o3) ind ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=1629723&group_id=4933 ```