Pythia8Interface/interface/P8RndmEngine.h

0001 #ifndef GeneratorInterface_Pythia8Interface_P8RndmEngine_h
0002 #define GeneratorInterface_Pythia8Interface_P8RndmEngine_h
0003
0004 /** \class gen::P8RndmEngine
0005
0006 Description: Used to set an external random number engine
0007 in Pythia 8.  Pythia 8 recognizes a class that has
0008 Pythia8::RndmEngine as a base class and a virtual
0009 flat method.  If you pass a pointer to an object of
0010 this class to Pythia 8 it will use it to generate
0011 random numbers.
0012
0013 Independent of Pythia 8, one can set the CLHEP
0014 engine that this class uses in its flat method.
0015
0016 \author W. David Dagenhart, created 26 November 2013
0017 */
0018
0019 #include "Pythia8/Basics.h"
0020
0021 namespace CLHEP {
0022   class HepRandomEngine;
0023 }
0024
0025 namespace gen {
0026
0027   class P8RndmEngine : public Pythia8::RndmEngine {
0028   public:
0029     P8RndmEngine() : randomEngine_(nullptr) {}
0030
0031     // Routine for generating a random number.
0032     double flat() override;
0033
0034     void setRandomEngine(CLHEP::HepRandomEngine* v) { randomEngine_ = v; }
0035
0036   private:
0037     void throwNullPtr() const;
0038
0039     CLHEP::HepRandomEngine* randomEngine_;
0040   };
0041   typedef std::shared_ptr<P8RndmEngine> P8RndmEnginePtr;
0042 }  // namespace gen
0043 #endif