[Boost-bugs] [Boost C++ Libraries] #6938: weibull_distribution accepts shape == 0, but shape should be >0

Subject: [Boost-bugs] [Boost C++ Libraries] #6938: weibull_distribution accepts shape == 0, but shape should be >0
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-05-24 12:46:31

#6938: weibull_distribution accepts shape == 0, but shape should be >0
-------------------------------------------------------------+--------------
 Reporter:  Florian Schoppmann <Florian.Schoppmann@…>        |       Owner:  johnmaddock
     Type:  Bugs                                             |      Status:  new        
Milestone:  To Be Determined                                 |   Component:  math       
  Version:  Boost 1.49.0                                     |    Severity:  Problem    
 Keywords:                                                   |  
-------------------------------------------------------------+--------------
 In function `check_weibull_shape()` in file
 `math/distributions/weibull.hpp` a domain error is only raised if `shape <
 0`. The error condition should probably be `shape <= 0`. With `shape ==
 0`, the Weibull distribution is not well-defined. Also, `shape == 0`
 contradicts the error message in the same function.

 E.g., the following example raises an overflow error, but not a domain
 error (as would be more appropriate IMHO):
 {{{
 #include <boost/math/distributions/weibull.hpp>
 using namespace boost::math;
 int main() {
     std::cout << mean(weibull(0)) << std::endl;
 }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/6938>
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