Opened 2 years ago
Last modified 5 hours ago
#23271 new defect
Wrong integration of abs(sin(x)*cos(x))
Reported by: | pdenapo | Owned by: | |
---|---|---|---|
Priority: | major | Milestone: | sage-8.0 |
Component: | symbolics | Keywords: | symbolic integration, absolute value, abs_integrate |
Cc: | Merged in: | ||
Authors: | Reviewers: | ||
Report Upstream: | N/A | Work issues: | |
Branch: | Commit: | ||
Dependencies: | Stopgaps: |
Description (last modified by )
Sage ignores the absolute value in the following symbolic integration.
sage: g=abs(sin(x)*cos(x)) sage: g.integrate(0,2*pi) 0
(the right result is 2, the integrand is positive in the interval so the integral can never be 0!
sage: version() 'SageMath version 7.6, Release Date: 2017-03-25'
Change History (5)
comment:1 Changed 2 years ago by
- Description modified (diff)
comment:2 follow-up: ↓ 3 Changed 2 years ago by
comment:3 in reply to: ↑ 2 Changed 2 years ago by
- Summary changed from Wrong intergation of abs(sin(x)*cos(x)) to Wrong integration of abs(sin(x)*cos(x))
Replying to mforets:
(should we submit a new upstream report for this one? since they seem to be so related).
Don't think so.
comment:4 Changed 4 weeks ago by
- Keywords abs_integrate added
comment:5 Changed 5 hours ago by
fixed by #27958, that needs review
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from v.8.0 those abs-integrands can be handled with the Giac interface:
besides, there are several related tickets in the symbolic wiki -- integration. there is a link to one Maxima's upstream report in #17511 (should we submit a new upstream report for this one? since they seem to be so related).