mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2024-11-17 01:22:15 -05:00
134 lines
4.0 KiB
C++
134 lines
4.0 KiB
C++
// Copyright John Maddock 2007.
|
|
// Copyright Paul a. Bristow 2010
|
|
// Use, modification and distribution are subject to 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)
|
|
|
|
// Note that this file contains quickbook mark-up as well as code
|
|
// and comments, don't change any of the special comment mark-ups!
|
|
|
|
#ifdef _MSC_VER
|
|
# pragma warning (disable : 4100) // unreferenced formal parameters
|
|
#endif
|
|
|
|
#include <iostream>
|
|
using std::cout; using std::endl; using std::cerr;
|
|
|
|
//[policy_eg_8
|
|
|
|
/*`
|
|
Suppose we want our own user-defined error handlers rather than the
|
|
any of the default ones supplied by the library to be used.
|
|
If we set the policy for a specific type of error to `user_error`
|
|
then the library will call a user-supplied error handler.
|
|
These are forward declared, but not defined in
|
|
boost/math/policies/error_handling.hpp like this:
|
|
|
|
namespace boost{ namespace math{ namespace policies{
|
|
|
|
template <class T>
|
|
T user_domain_error(const char* function, const char* message, const T& val);
|
|
template <class T>
|
|
T user_pole_error(const char* function, const char* message, const T& val);
|
|
template <class T>
|
|
T user_overflow_error(const char* function, const char* message, const T& val);
|
|
template <class T>
|
|
T user_underflow_error(const char* function, const char* message, const T& val);
|
|
template <class T>
|
|
T user_denorm_error(const char* function, const char* message, const T& val);
|
|
template <class T>
|
|
T user_evaluation_error(const char* function, const char* message, const T& val);
|
|
template <class T, class TargetType>
|
|
T user_rounding_error(const char* function, const char* message, const T& val, const TargetType& t);
|
|
template <class T>
|
|
T user_indeterminate_result_error(const char* function, const char* message, const T& val);
|
|
|
|
}}} // namespaces
|
|
|
|
So out first job is to include the header we want to use, and then
|
|
provide definitions for our user-defined error handlers that we want to use.
|
|
We only provide our special domain and pole error handlers;
|
|
other errors like overflow and underflow use the default.
|
|
*/
|
|
|
|
#include <boost/math/special_functions.hpp>
|
|
|
|
namespace boost{ namespace math
|
|
{
|
|
namespace policies
|
|
{
|
|
template <class T>
|
|
T user_domain_error(const char* function, const char* message, const T& val)
|
|
{ // Ignoring function, message and val for this example, perhaps unhelpfully.
|
|
cerr << "Domain Error!" << endl;
|
|
return std::numeric_limits<T>::quiet_NaN();
|
|
}
|
|
|
|
template <class T>
|
|
T user_pole_error(const char* function, const char* message, const T& val)
|
|
{ // Ignoring function, message and val for this example, perhaps unhelpfully.
|
|
cerr << "Pole Error!" << endl;
|
|
return std::numeric_limits<T>::quiet_NaN();
|
|
}
|
|
} // namespace policies
|
|
}} // namespace boost{ namespace math
|
|
|
|
|
|
/*`
|
|
Now we'll need to define a suitable policy that will call these handlers,
|
|
and define some forwarding functions that make use of the policy:
|
|
*/
|
|
|
|
namespace mymath{
|
|
|
|
using namespace boost::math::policies;
|
|
|
|
typedef policy<
|
|
domain_error<user_error>,
|
|
pole_error<user_error>
|
|
> user_error_policy;
|
|
|
|
BOOST_MATH_DECLARE_SPECIAL_FUNCTIONS(user_error_policy)
|
|
|
|
} // close unnamed namespace
|
|
|
|
/*`
|
|
We now have a set of forwarding functions defined in namespace mymath
|
|
that all look something like this:
|
|
|
|
``
|
|
template <class RealType>
|
|
inline typename boost::math::tools::promote_args<RT>::type
|
|
tgamma(RT z)
|
|
{
|
|
return boost::math::tgamma(z, user_error_policy());
|
|
}
|
|
``
|
|
|
|
So that when we call `mymath::tgamma(z)` we really end up calling
|
|
`boost::math::tgamma(z, user_error_policy())`, and any
|
|
errors will get directed to our own error handlers.
|
|
*/
|
|
|
|
int main()
|
|
{
|
|
cout << "Result of erf_inv(-10) is: "
|
|
<< mymath::erf_inv(-10) << endl;
|
|
cout << "Result of tgamma(-10) is: "
|
|
<< mymath::tgamma(-10) << endl;
|
|
}
|
|
|
|
/*`
|
|
|
|
Which outputs:
|
|
|
|
[pre
|
|
Domain Error!
|
|
Pole Error!
|
|
Result of erf_inv(-10) is: 1.#QNAN
|
|
Result of tgamma(-10) is: 1.#QNAN
|
|
]
|
|
*/
|
|
|
|
//] // //[/policy_eg_8]
|