Re: [Boost-bugs] [Boost C++ Libraries] #7290: complex acos is occasionally wrong

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7290: complex acos is occasionally wrong
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-08-26 19:02:08

#7290: complex acos is occasionally wrong
--------------------------------------------------------------+-------------
  Reporter:  Stephen Montgomery-Smith <stephen@…>             |       Owner:  johnmaddock
      Type:  Bugs                                             |      Status:  new        
 Milestone:  To Be Determined                                 |   Component:  math       
   Version:  Boost 1.52.0                                     |    Severity:  Problem    
Resolution:                                                   |    Keywords:             
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Comment (by Stephen Montgomery-Smith <stephen@…>):

 Looking at page 327 of the paper by Hull et al, they say that the real
 part can be set to zero, because the absolute error will be negligible
 compared to the absolute error in the imaginary part.  But everywhere else
 in the paper, they manage to control the relative error of the real and
 imaginary parts separately.

 Looking at page 304, it seems that their goal is only to control the
 relative error of the real and imaginary parts together.  So this wasn't
 really a mistake in their paper.

 But I think the "higher goal" of controlling the relative error of the
 real and imaginary parts separately is worthy, so I still commend my patch
 to you.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7290#comment:3>
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