Re: [Boost-bugs] [Boost C++ Libraries] #10110: boost::random::negative_binomial_distribution unnecessary restriction to IntType for parameter k

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #10110: boost::random::negative_binomial_distribution unnecessary restriction to IntType for parameter k
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-03-11 08:28:41

#10110: boost::random::negative_binomial_distribution unnecessary restriction to
IntType for parameter k
-------------------------------------+-------------------------------------
  Reporter:  Maximilian Kleinert     |      Owner:  no-maintainer
  <kleinert.max@…>                   |     Status:  new
      Type:  Bugs                    |  Component:  random
 Milestone:  To Be Determined        |   Severity:  Problem
   Version:  Boost 1.55.0            |   Keywords:  random, negative
Resolution:                          |  binomial distribution
-------------------------------------+-------------------------------------

Comment (by Maximilian Kleinert <kleinert.max@…>):

 Replying to [comment:4 steven_watanabe]:
 > k = 0 and p = 1 are degenerate cases which should be supported.

 The case p = 1 (regardless of k) is not supported by the boost version:
 The gamma distribution fails because the parameter beta = (1-p)/p is not
 greater than zero.
 The standard version fails if compiled with -D_GLIBCXX_DEBUG using g++.

 The working draft standard (N4926) page 965 requires: 0 < p <= 1 and 0 <
 k.

 Boost and standard version (except compiled with -D_GLIBCXX_DEBUG) return
 in the case p = 0 the sample -2147483648 which is not very useful.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10110#comment:6>
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