[Boost-bugs] [Boost C++ Libraries] #10103: setprecision(0) does displays too many digits of a float128

Subject: [Boost-bugs] [Boost C++ Libraries] #10103: setprecision(0) does displays too many digits of a float128
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-06-07 12:38:29

#10103: setprecision(0) does displays too many digits of a float128
----------------------------------------+----------------------------
 Reporter:  Charles Karney <charles@…>  |      Owner:  johnmaddock
     Type:  Bugs                        |     Status:  new
Milestone:  To Be Determined            |  Component:  multiprecision
  Version:  Boost 1.54.0                |   Severity:  Problem
 Keywords:  printing                    |
----------------------------------------+----------------------------
 setprecision(0) is not honored for float128.  Compare
 the display of a double and a float128 (default and fixed):

 {{{
 0.1 0.123400000000000000000000000000000006
 0 0.123400000000000000000000000000000006
 }}}

 This is produced with

 {{{
 #include <iostream>
 #include <boost/multiprecision/float128.hpp>

 int main() {
   double x = 0.1234;
   boost::multiprecision::float128 y = 0.1234Q;
   std::cout << std::setprecision(0) << x << " " << y << "\n";
   std::cout << std::fixed << x << " " << y << "\n";
 }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10103>
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