[Maxima-bugs] [ maxima-Bugs-3034140 ] incorrect integration of %e^(-(x^2*a^2))*cos(b*x)

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Bugs item #3034140, was opened at 2010-07-24 18:34
Message generated for change (Comment added) made by dgildea
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Category: None
Group: None
>Status: Closed
>Resolution: Fixed
Priority: 5
Private: No
Submitted By: caprilo (caprilo)
Assigned to: Nobody/Anonymous (nobody)
Summary: incorrect integration of %e^(-(x^2*a^2))*cos(b*x)

Initial Comment:
The result of

integrate(exp(-(x^2*a^2))*cos(b*x),x,-inf,inf);

is 0 no matter if you answer that a is or is not 0. The result should be

sqrt(%pi)*exp(-b^2/(4*a^2))

Strangely, the result of

integrate(exp(-(x^2*a^2))*cos(b*x),x,0,inf);

is "und" (the integrand is even), and the result of

integrate(exp(-(x^2))*cos(b*x),x,-inf,inf);

is correct.
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Maxima version: 5.21.1
Maxima build date: 16:9 6/10/2010
Host type: x86_64-unknown-linux-gnu
Lisp implementation type: GNU Common Lisp (GCL)
Lisp implementation version: GCL 2.6.7

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>Comment By: Dan Gildea (dgildea)
Date: 2010-07-26 13:41

Message:
Fixed in defint.lisp rev 1.79


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https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3034140&group_id=4933