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

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #10103: setprecision(0) does displays too many digits of a float128
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-10-14 14:40:49

#10103: setprecision(0) does displays too many digits of a float128
-----------------------------------------+----------------------------
  Reporter:  Charles Karney <charles@…>  |      Owner:  johnmaddock
      Type:  Bugs                        |     Status:  assigned
 Milestone:  To Be Determined            |  Component:  multiprecision
   Version:  Boost 1.54.0                |   Severity:  Problem
Resolution:                              |   Keywords:  printing
-----------------------------------------+----------------------------

Comment (by Charles Karney <charles@…>):

 With C++11 manipulators, I recommend that

 {{{
 cout << scientific << setprecision(0) << x;
 cout << hexfloat << setprecision(0) << x;
 }}}

 should print lossless representations of x.  While

 {{{
 cout << fixed << setprecision(0) << x;
 cout << defaultfloat << setprecision(0) << x;
 }}}

 should mimic whatever the standard library does with doubles.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10103#comment:4>
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