1
0
Fork 0
mirror of https://github.com/cosmo-sims/MUSIC.git synced 2024-09-10 06:43:45 +02:00
MUSIC/src/Numerics.cc
2024-02-24 10:52:43 +01:00

56 lines
1.6 KiB
C++

// This file is part of MUSIC
// A software package to generate ICs for cosmological simulations
// Copyright (C) 2010-2024 by Oliver Hahn
//
// monofonIC is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// monofonIC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#ifdef WITH_MPI
#ifdef MANNO
#include <mpi.h>
#else
#include <mpi++.h>
#endif
#endif
#include <iostream>
#include "Numerics.hh"
#ifndef REL_PRECISION
#define REL_PRECISION 1.e-5
#endif
real_t integrate( double (* func) (double x, void * params), double a, double b, void *params )
{
gsl_function F;
F.function = func;
F.params = params;
double result;
double error;
gsl_set_error_handler_off ();
gsl_integration_workspace *w = gsl_integration_workspace_alloc(100000);
gsl_integration_qag( &F, a, b, 0, REL_PRECISION, 100000, 6, w, &result, &error );
gsl_integration_workspace_free(w);
gsl_set_error_handler(NULL);
if( error/result > REL_PRECISION )
std::cerr << " - Warning: no convergence in function 'integrate', rel. error=" << error/result << std::endl;
return (real_t)result;
}