PythiaStdlib.h

// PythiaStdlib.h is a part of the PYTHIA event generator.
// Copyright (C) 2014 Torbjorn Sjostrand.
// PYTHIA is licenced under the GNU GPL version 2, see COPYING for details.
// Please respect the MCnet Guidelines, see GUIDELINES for details.

// Header file for functionality pulled in from Stdlib,
// plus a few useful utilities (small powers; positive square root,
// Gamma function).

#ifndef Pythia8_PythiaStdlib_H
#define Pythia8_PythiaStdlib_H

// Stdlib header files for mathematics.
#include <cmath>
#include <cstdlib>
#include <algorithm>

// Stdlib header files for strings and containers.
#include <string>
#include <vector>
#include <map>
#include <deque>
#include <set>

// Stdlib header file for input and output.
#include <iostream>
#include <iomanip>
#include <fstream>
#include <sstream>

// Define pi if not yet done.
#ifndef M_PI
#define M_PI 3.1415926535897932385
#endif

// By this declaration you do not need to use std:: qualifier everywhere.
//using namespace std;

// Alternatively you can specify exactly which std:: methods will be used.
// Now made default so std does not spill outside namespace Pythia8.
namespace Pythia8 {

// Generic utilities and mathematical functions.
using std::swap;
using std::max;
using std::min;
using std::abs;
using std::sort;

// Strings and containers.
using std::pair;
using std::make_pair;
using std::string;
using std::vector;
using std::map;
using std::multimap;
using std::deque;
using std::set;

// Input/output streams.
using std::cin;
using std::cout;
using std::cerr;
using std::istream;
using std::ostream;
using std::fstream;
using std::ifstream;
using std::ofstream;
using std::stringstream;
using std::istringstream;
using std::ostringstream;
using std::ios;

// Input/output formatting.
using std::endl;
using std::fixed;
using std::scientific;
using std::left;
using std::right;
using std::setw;
using std::setprecision;
 
} // end namespace Pythia8

namespace Pythia8 {

// Powers of small integers - for balance speed/code clarity.
inline double pow2(const double& x) {return x*x;}
inline double pow3(const double& x) {return x*x*x;}
inline double pow4(const double& x) {return x*x*x*x;}
inline double pow5(const double& x) {return x*x*x*x*x;}
inline double pow6(const double& x) {return x*x*x*x*x*x;}

// Avoid problem with negative square root argument (from roundoff).
inline double sqrtpos(const double& x) {return sqrt( max( 0., x));}

// The Gamma function for real argument.
double GammaReal(double x);

} // end namespace Pythia8

#endif // Pythia8_PythiaStdlib_H