ThePEG/Repository/StandardRandom.h

0001 // -*- C++ -*-
0002 //
0003 // StandardRandom.h is a part of ThePEG - Toolkit for HEP Event Generation
0004 // Copyright (C) 1999-2019 Leif Lonnblad
0005 //
0006 // ThePEG is licenced under version 3 of the GPL, see COPYING for details.
0007 // Please respect the MCnet academic guidelines, see GUIDELINES for details.
0008 //
0009 #ifndef ThePEG_StandardRandom_H
0010 #define ThePEG_StandardRandom_H
0011 // This is the declaration of the StandardRandom class.
0012
0013 #include "RandomGenerator.h"
0014 #include "ThePEG/Persistency/PersistentOStream.h"
0015 #include "ThePEG/Persistency/PersistentIStream.h"
0016
0017 namespace ThePEG {
0018
0019 /**
0020  * StandardRandom inherits from the RandomGenerator class and is an
0021  * interface to the CLHEP::JamesRandom engine class.
0022  *
0023  * @see \ref StandardRandomInterfaces "The interfaces"
0024  * defined for StandardRandom.
0025  */
0026 class StandardRandom: public RandomGenerator {
0027
0028 public:
0029
0030   /** @name Standard constructors and destructors. */
0031   //@{
0032   /**
0033    * Default constructor.
0034    */
0035   StandardRandom() : u() { if ( theSeed != 0 ) setSeed(theSeed); }
0036   //@}
0037
0038 public:
0039
0040   /**
0041    * Reset the underlying random algorithm with the given seed. If the
0042    * \a seed is set to -1 a standard seed will be used.
0043    */
0044   virtual void setSeed(long seed);
0045
0046 protected:
0047
0048   /**
0049    * Fill the cache with random numbers.
0050    */
0051   virtual void fill();
0052
0053 public:
0054
0055
0056   /** @name Functions used by the persistent I/O system. */
0057   //@{
0058   /**
0059    * Function used to write out object persistently.
0060    * @param os the persistent output stream written to.
0061    */
0062   void persistentOutput(PersistentOStream & os) const;
0063
0064   /**
0065    * Function used to read in object persistently.
0066    * @param is the persistent input stream read from.
0067    * @param version the version number of the object when written.
0068    */
0069   void persistentInput(PersistentIStream & is, int version);
0070   //@}
0071
0072   /**
0073    * Standard Init function used to initialize the interface.
0074    */
0075   static void Init();
0076
0077 protected:
0078
0079   /** @name Clone Methods. */
0080   //@{
0081   /**
0082    * Make a simple clone of this object.
0083    * @return a pointer to the new object.
0084    */
0085   virtual IBPtr clone() const;
0086
0087   /** Make a clone of this object, possibly modifying the cloned object
0088    * to make it sane.
0089    * @return a pointer to the new object.
0090    */
0091   virtual IBPtr fullclone() const;
0092   //@}
0093
0094 private:
0095
0096   /**
0097    * The internal state vector.
0098    */
0099   array<double,97> u;
0100
0101   /**
0102    * Parameter for the internal state.
0103    */
0104   double c;
0105
0106   /**
0107    * Parameter for the internal state.
0108    */
0109   double cd;
0110
0111   /**
0112    * Parameter for the internal state.
0113    */
0114   double cm;
0115
0116   /**
0117    * Index for the internal state.
0118    */
0119   int i97;
0120
0121   /**
0122    * Index for the internal state.
0123    */
0124   int j97;
0125
0126 private:
0127
0128   /**
0129    * Describe a concrete class with persistent data.
0130    */
0131   static ClassDescription<StandardRandom> initStandardRandom;
0132
0133   /**
0134    *  Private and non-existent assignment operator.
0135    */
0136   StandardRandom & operator=(const StandardRandom &) = delete;
0137
0138 };
0139
0140 /** @cond TRAITSPECIALIZATIONS */
0141
0142 /** This template specialization informs ThePEG about the base classes
0143  *  of StandardRandom. */
0144 template <>
0145 struct BaseClassTrait<StandardRandom,1>: public ClassTraitsType {
0146   /** Typedef of the first base class of StandardRandom. */
0147   typedef RandomGenerator NthBase;
0148 };
0149
0150 /** This template specialization informs ThePEG about the name of the
0151  *  StandardRandom class. */
0152 template <>
0153 struct ClassTraits<StandardRandom>: public ClassTraitsBase<StandardRandom> {
0154   /** Return a platform-independent class name */
0155   static string className() { return "ThePEG::StandardRandom"; }
0156 };
0157
0158 /** @endcond */
0159
0160 }
0161
0162 #endif /* ThePEG_StandardRandom_H */