[Boost-bugs] [Boost C++ Libraries] #11532: toms748_solve produces -nan when evaluating a smooth function in a fixed interval

Subject: [Boost-bugs] [Boost C++ Libraries] #11532: toms748_solve produces -nan when evaluating a smooth function in a fixed interval
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-08-10 10:19:08

#11532: toms748_solve produces -nan when evaluating a smooth function in a fixed
interval
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 Reporter:  Ola Skavhaug <ola@…>  |      Owner:  johnmaddock
     Type:  Bugs                  |     Status:  new
Milestone:  To Be Determined      |  Component:  math
  Version:  Boost 1.57.0          |   Severity:  Problem
 Keywords:                        |
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 In my algorithm that is finding the point where two gamma gamma
 distributions crosses, the toms748 solver produces a -nan value for the
 evaluation point. The behaviour occurs quite rarely, and only for
 extremely specific values of the governing parameters. I have not checked
 if the problem is cross platform.

 I see that the solver evaluates the same point twice, and suspect that the
 subsequent calculation of the change of the evaluation point somehow
 divides by 0.

 A minimal example is enclosed.

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Ticket URL: <https://svn.boost.org/trac/boost/ticket/11532>
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