Opened 3 years ago
Closed 2 years ago
#10914 closed defect (fixed)
Integration involving abs gives wrong result
Reported by: | poeschko | Owned by: | burcin |
---|---|---|---|
Priority: | major | Milestone: | sage-5.0 |
Component: | calculus | Keywords: | |
Cc: | Merged in: | sage-5.0.beta14 | |
Authors: | Michael Orlitzky | Reviewers: | Karl-Dieter Crisman |
Report Upstream: | Fixed upstream, in a later stable release. | Work issues: | |
Branch: | Commit: | ||
Dependencies: | Stopgaps: |
Description (last modified by kcrisman)
Running
sage: integrate(abs(sin(x)),(x,0,2*pi))
gives 0, but the correct result is 4.
This happens in version 4.6.1 . In 4.5.3, the integral was not evaluated at all.
Apply trac_10914.patch.
Attachments (1)
Change History (9)
comment:1 Changed 3 years ago by kcrisman
- Report Upstream changed from N/A to Reported upstream. Little or no feedback.
comment:2 Changed 3 years ago by kcrisman
- Report Upstream changed from Reported upstream. Little or no feedback. to Fixed upstream, but not in a stable release.
Apparently that was a dup - see this bug report instead. Fixed, so when we upgrade we'll need a doctest.
comment:3 Changed 2 years ago by mjo
- Report Upstream changed from Fixed upstream, but not in a stable release. to Fixed upstream, in a later stable release.
- Status changed from new to needs_review
Well, we don't get 4, but at least the bug is fixed with our current Maxima.
comment:4 Changed 2 years ago by kcrisman
- Reviewers set to Karl-Dieter Crisman
- Status changed from needs_review to positive_review
shouln't?
Anyway, this is fine, but the style is a little too informal - those not having read the ticket will be mystified, and shouldn't have to go to the ticket to find out. So I'm uploading the same patch but with slightly different wording.
Notwithstanding that this file doesn't appear to be in the reference manual in any case.
comment:6 Changed 2 years ago by mjo
Ah, sorry. I actually parse it now as, "We won't get (an evaluated answer here, which is better than the previous (wrong) answer of zero)," but I don't think it matters much since most of them don't make sense out-of-context, "make sure #xyz is fixed."
comment:7 Changed 2 years ago by jdemeyer
- Milestone set to sage-5.0
comment:8 Changed 2 years ago by jdemeyer
- Merged in set to sage-5.0.beta14
- Resolution set to fixed
- Status changed from positive_review to closed
Certainly the integral better be positive!
This is wrong in Maxima (5.23.2), though it does get the one arch problem correct:
This is now Maxima bug 3211915.