Re: [Boost-bugs] [Boost C++ Libraries] #4812: Bug in boost::math::special_functions::sign showing up in special_functions::bessel_jy()

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #4812: Bug in boost::math::special_functions::sign showing up in special_functions::bessel_jy()
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-11-04 11:40:47

#4812: Bug in boost::math::special_functions::sign showing up in
special_functions::bessel_jy()
----------------------------------------------+-----------------------------
  Reporter:  peter zwart <PHZwart@…>          |       Owner:  johnmaddock                     
      Type:  Bugs                             |      Status:  new                             
 Milestone:  To Be Determined                 |   Component:  math                            
   Version:  Boost 1.45.0                     |    Severity:  Showstopper                     
Resolution:                                   |    Keywords:  sign sph_bessel special_function
----------------------------------------------+-----------------------------

Comment (by anonymous):

 Hi Peter,

 I'm unable to reproduce here, so I need your help as the implementation of
 boost::math::sign is platform/compiler dependent, so I have a bunch of
 questions for you I'm afraid:

 1) What compiler / platform / architecture is this?
 2) Can check the return value of boost::math::sign(-1.24911e-2468L); and
 verify that this returns an incorrect result?
 3) If (2) does return an incorrect result, can you please step though it's
 code and let me know which of the implementations of signbit_impl in
 sign.hpp is in use?

 Many thanks, John Maddock.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4812#comment:1>
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