#2692 Integration of a Complicated Function Crashes in 5.32.1

None
open
nobody
None
5
2014-02-23
2014-02-23
Sean Lake
No

This one's fairly straightforward to trigger:

fun : n/(2 * %pi * sigt * sigr) * exp( -1/(2 * sigt^2) * ( n * logtheta - log( thetasee^n + exp(n * logr) / Da^n ) )^2 - 1/(2 * sigr^2) * ( logr - mu_r )^2 );
integrate( fun, logr, minf, inf );

Is n positive, negative or zero?

pos;
Is mu_r positive, negative or zero?

pos;
[...]
Binding stack exhausted.
[...]

According to Robert Dodier on the maxima-discuss list:
"[A] little debugging indicates that Maxima gets
stuck in LIMIT calling SIMPLIMIT calling SIMPLIMLN calling LIMIT ..."
[...]
"I find that I can avoid error by asserting that various constants
are positive. I don't know why that avoids the problem.

assume (n > 0, mu_r > 0, sigr > 0, sigt > 0);
integrate (fun, logr, minf, inf);
=> ('integrate noun expression)"

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