[Boost-bugs] [Boost C++ Libraries] #2512: interval cosh: wrong result if interval contains 0 (but is not identical to [0, 0])

Subject: [Boost-bugs] [Boost C++ Libraries] #2512: interval cosh: wrong result if interval contains 0 (but is not identical to [0, 0])
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2008-11-19 09:12:58

#2512: interval cosh: wrong result if interval contains 0 (but is not identical to
[0,0])
--------------------------------------------+-------------------------------
 Reporter:  stephan.puchegger_at_[hidden]  |       Owner:  bgubenko   
     Type:  Bugs                            |      Status:  new        
Milestone:  Boost 1.38.0                    |   Component:  interval   
  Version:  Boost 1.37.0                    |    Severity:  Showstopper
 Keywords:                                  |  
--------------------------------------------+-------------------------------
 The last line (line 179) of the cosh function in the file transc.hpp
 should imho read:

 return I(static_cast<T>(1), rnd.cosh_up(-x.lower() > x.upper() ? x.lower()
 : x.upper()), true);

 instead of

 return I(static_cast<T>(0), rnd.cosh_up(-x.lower() > x.upper() ? x.lower()
 : x.upper()), true);

 since the cosh(0) == 1. Otherwise the function will return the wrong
 result.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2512>
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