[Boost-bugs] [Boost C++ Libraries] #9966: exponential_distribution returns negative zero with single precision float

Subject: [Boost-bugs] [Boost C++ Libraries] #9966: exponential_distribution returns negative zero with single precision float
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-04-30 10:23:40

#9966: exponential_distribution returns negative zero with single precision float
------------------------------+---------------------------
 Reporter:  mazzamuto@…       |      Owner:  no-maintainer
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  random
  Version:  Boost 1.55.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+---------------------------
 The code below produces this output:

 1.72296[[BR]]
 -0[[BR]]
 0.295209[[BR]]
 0.210905[[BR]]
 0.930678[[BR]]

 {{{
 #!c++
 #include <fstream>
 #include <boost/random.hpp>

 using namespace boost::random;
 using namespace std;

 int main() {
     ifstream mtfile;
     mtfile.open("mt.dat"); //see attached file
     mt19937 mt;
     mtfile >> mt;
     mtfile.close();

     for (int i = 0; i < 5; ++i) {
         cout << exponential_distribution<float>(1.f)(mt) << endl;
     }

     return 0;
 }

 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9966>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.