Re: [Boost-bugs] [Boost C++ Libraries] #5433: beta function: when b<epsilon return tgamma(b)?

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5433: beta function: when b<epsilon return tgamma(b)?
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-04-07 10:08:18

#5433: beta function: when b<epsilon return tgamma(b)?
-----------------------------------------------+----------------------------
  Reporter:  Eric Butter <egbutter@…>          |       Owner:  johnmaddock
      Type:  Bugs                              |      Status:  closed     
 Milestone:  To Be Determined                  |   Component:  math       
   Version:  Boost 1.47.0                      |    Severity:  Problem    
Resolution:  invalid                           |    Keywords:             
-----------------------------------------------+----------------------------
Changes (by johnmaddock):

  * status:  new => closed
  * resolution:  => invalid

Comment:

 I believe the code to be correct:

 if a >> b such that a + b == a (at the precision we're working to), then:

 gamma(a) / gamma(a+b) == 1

 so:

 beta(a, b) = gamma(a) * gamma(b) / gamma(a+b) ~ gamma(b) ~ 1/b

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5433#comment:1>
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