symbolic integration fails on a very simple test case

[pdehaye]

The following happens

sage: var("x")
x
sage: integrate(abs(x - 1) + abs(x + 1) - 2*abs(x), (x,-Infinity,Infinity))
0
sage: integrate(abs(x - 1) + abs(x + 1) - 2*abs(x),(x,-Infinity,10))
2

The second answer is the correct one, of course...

Upstream: Fixed upstream, in a later stable release.

CC: @kcrisman

Component: calculus

Keywords: integrate

Author: Michael Orlitzky

Reviewer: Karl-Dieter Crisman

Merged: sage-5.0.beta11

Issue created by migration from https://trac.sagemath.org/ticket/11445

[kcrisman]

comment:1

This also happens in Maxima.

Maxima 5.24.0 http://maxima.sourceforge.net
using Lisp SBCL 1.0.24
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1) integrate(abs(x - 1) + abs(x + 1) - 2*abs(x),x,minf,10);
(%o1)                                  2
(%i2) integrate(abs(x - 1) + abs(x + 1) - 2*abs(x),x,minf,inf);
(%o2)                                  0

I don't know that I would call this "very simple", though, as integrating absolute value things is somewhat tricky when done symbolically.

[kcrisman]

Upstream: Not yet reported upstream; Will do shortly.

[pdehaye]

comment:2

sure, but certainly something i would hope works! also not sure how much of it is due to the infinite interval and how much due to the function itself

[kcrisman]

comment:3

This is now reported at this location.

[kcrisman]

Changed upstream from Not yet reported upstream; Will do shortly. to Reported upstream. Little or no feedback.

[pdehaye]

comment:4

fixed over there

[pdehaye]

Changed upstream from Reported upstream. Little or no feedback. to Fixed upstream, in a later stable release.

[orlitzky]

Doctest for the correct result.