mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2025-10-28 11:30:25 -04:00
116 lines
3.6 KiB
C++
116 lines
3.6 KiB
C++
|
|
/** nonfinite_num_facet_trap.cpp
|
|
*
|
|
* Copyright (c) 2012 Paul A. Bristow
|
|
*
|
|
* Distributed under the Boost Software License, Version 1.0.
|
|
* (See accompanying file LICENSE_1_0.txt
|
|
* or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
*
|
|
* This very simple program illustrates how to use the
|
|
* `boost/math/nonfinite_num_facets.hpp` trapping output of infinity and/or NaNs.
|
|
*
|
|
\file
|
|
|
|
\brief A very simple example of using non_finite_num facet for
|
|
trapping output of infinity and/or NaNs.
|
|
|
|
\note To actually get an exception throw by the iostream library
|
|
one must enable exceptions.
|
|
`oss.exceptions(std::ios_base::failbit | std::ios_base::badbit);`
|
|
\note Which bit is set is implementation dependent, so enable exceptions for both.
|
|
|
|
This is a fairly brutal method of catching nonfinites on output,
|
|
but may suit some applications.
|
|
|
|
*/
|
|
|
|
#ifdef _MSC_VER
|
|
# pragma warning(disable : 4127) // conditional expression is constant.
|
|
// assumes C++ exceptions enabled /EHsc
|
|
#endif
|
|
|
|
#include <boost/cstdint.hpp>
|
|
#include <boost/math/special_functions/nonfinite_num_facets.hpp>
|
|
|
|
#include <iostream>
|
|
#include <iomanip>
|
|
using std::cout;
|
|
using std::endl;
|
|
using std::hex;
|
|
#include <exception>
|
|
#include <limits> // numeric_limits
|
|
using std::numeric_limits;
|
|
|
|
int main()
|
|
{
|
|
using namespace boost::math;
|
|
|
|
std::cout << "nonfinite_num_facet_trap.cpp" << std::endl;
|
|
|
|
const double inf = +std::numeric_limits<double>::infinity ();
|
|
const double nan = +std::numeric_limits<double>::quiet_NaN ();
|
|
|
|
{ // Output infinity and NaN with default flags (no trapping).
|
|
std::ostringstream oss;
|
|
std::locale default_locale (std::locale::classic ());
|
|
std::locale C99_out_locale (default_locale, new boost::math::nonfinite_num_put<char>);
|
|
oss.imbue (C99_out_locale);
|
|
oss.exceptions(std::ios_base::failbit | std::ios_base::badbit);
|
|
oss << inf << ' ' << nan;
|
|
cout << "oss.rdstate() = " << hex << oss.rdstate() << endl; // 0
|
|
cout << "os.str() = " << oss.str() << endl; // os.str() = inf nan
|
|
}
|
|
|
|
try
|
|
{ // // Output infinity with flags set to trap and catch any infinity.
|
|
std::ostringstream oss;
|
|
std::locale default_locale (std::locale::classic ());
|
|
std::locale C99_out_locale (default_locale, new boost::math::nonfinite_num_put<char>(trap_infinity));
|
|
oss.imbue (C99_out_locale);
|
|
oss.exceptions(std::ios_base::failbit | std::ios_base::badbit);
|
|
// Note that which bit is set is implementation dependent, so enable exceptions for both.
|
|
oss << inf;
|
|
cout << "oss.rdstate() = " << hex << oss.rdstate() << endl;
|
|
cout << "oss.str() = " << oss.str() << endl;
|
|
}
|
|
catch(const std::ios_base::failure& e)
|
|
{ // Expect "Infinity".
|
|
std::cout << "\n""Message from thrown exception was: " << e.what() << std::endl;
|
|
}
|
|
|
|
try
|
|
{ // // Output NaN with flags set to catch any NaNs.
|
|
std::ostringstream oss;
|
|
std::locale default_locale (std::locale::classic ());
|
|
std::locale C99_out_locale (default_locale, new boost::math::nonfinite_num_put<char>(trap_nan));
|
|
oss.imbue (C99_out_locale);
|
|
oss.exceptions(std::ios_base::failbit | std::ios_base::badbit);
|
|
// Note that which bit is set is implementation dependent, so enable exceptions for both.
|
|
oss << nan;
|
|
cout << "oss.str() = " << oss.str() << endl;
|
|
}
|
|
catch(const std::ios_base::failure& e)
|
|
{ // Expect "Infinity".
|
|
std::cout << "\n""Message from thrown exception was: " << e.what() << std::endl;
|
|
}
|
|
|
|
|
|
return 0; // end of nonfinite_num_facet_trap.cpp
|
|
} // int main()
|
|
|
|
|
|
/*
|
|
|
|
Output:
|
|
|
|
nonfinite_num_facet_trap.cpp
|
|
oss.rdstate() = 0
|
|
os.str() = inf nan
|
|
|
|
Message from thrown exception was: Infinity
|
|
|
|
Message from thrown exception was: NaN
|
|
|
|
*/
|