incomplete_gamma_function.h

Go to the documentation of this file.

/* 
 * SPDX-FileCopyrightText: 2025 Gesellschaft fuer Anlagen- und Reaktorsicherheit gGmbH
 * SPDX-License-Identifier: EUPL-1.2
 * SPDX-FileContributor: Sabine Stichel
 * SPDX-FileContributor: Goethe Universität Frankfurt
 * SPDX-FileType: SOURCE
 * 
 * This file is part of d3f++.
 * d3f++ is an extension for UG4. Licensing information and citation requirements of UG4 are provided in LICENSES/UG4-LGPL_2.1
 */
 
 
/*
 * Original by J.Musuuza
 */
 
// extern headers
#include <iostream>
#include <sstream>
#include <fstream>
#include <string>
#include <cmath>
#include <vector>
 
 
#define _USE_MATH_DEFINES
#include <math.h>
#include <float.h> //for DBL_MAX
#include <iomanip>
#include <cstdlib>
#include <time.h>
#include "common/common.h"
 
#include "lib_disc/common/groups_util.h"
#include "lib_disc/common/function_group.h"
#include "lib_grid/tools/subset_group.h"
#include "bridge/bridge.h"
#include "lib_disc/domain.h"
#include "lib_disc/domain_traits.h"
#include "lib_algebra/cpu_algebra_types.h"
#include "lib_disc/quadrature/quadrature.h"
#include "lib_disc/local_finite_element/local_finite_element_provider.h"
#include "lib_disc/spatial_disc/disc_util/fv1_geom.h"
#include "lib_disc/spatial_disc/user_data/user_data.h"
#include "common/util/provider.h"
#include "lib_disc/spatial_disc/disc_util/fv1_geom.h"
#include "lib_disc/spatial_disc/disc_util/hfv1_geom.h"
#include "common/parser/rapidxml/rapidxml_print.hpp"
#include "common/parser/rapidxml/rapidxml.hpp"
#include "../plugins/experimental/biogas/save_load.h"
 
 
//using namespace std;
//using namespace rapidxml;
#ifdef UG_FOR_LUA
#include "bindings/lua/lua_user_data.h"
#endif
 
namespace ug{
namespace d3f{
 
/*functions copied from:  incomplete_gamma_function.c*/
 
template <typename TData, int dim, typename TRet>
double FractalField<TData,dim,TRet>::Incomplete_Gamma_Function(double x, double nu)
{
   return (double) xIncomplete_Gamma_Function((long double)x, (long double)nu);
}
 
 
template <typename TData, int dim, typename TRet>
long double FractalField<TData,dim,TRet>::xIncomplete_Gamma_Function(long double x, long double nu)
{
   if ( x == 0.0L )
     return 0.0L;
   if ( nu <= Gamma_Function_Max_Arg() )
      return xEntire_Incomplete_Gamma_Function(x,nu) * xGamma_Function(nu);
   else
     return expl(logl(xEntire_Incomplete_Gamma_Function(x,nu)) + xLn_Gamma_Function(nu));
}
 
 
 
}
}