00001 // $Id: DRand48Engine.h,v 1.20 2002/04/12 15:02:44 evc Exp $ 00002 // -*- C++ -*- 00003 // 00004 // ----------------------------------------------------------------------- 00005 // HEP Random 00006 // --- DRand48Engine --- 00007 // class header file 00008 // ----------------------------------------------------------------------- 00009 // This file is part of Geant4 (simulation toolkit for HEP). 00010 // 00011 // Random engine using drand48() and srand48() functions from C standard 00012 // library to implement the flat() basic distribution and for setting 00013 // seeds. 00014 // For Windows/NT platforms (WIN32), the code for drand48 has been 00015 // extracted from the GNU C Library 2.0.1 and adapted for the native 00016 // types. 00017 // Copy constructor and operator= are private for objects of this class. 00018 00019 // ======================================================================= 00020 // G.Cosmo - Created: 5th September 1995 00021 // - Minor corrections: 31st October 1996 00022 // - Added methods for engine status: 19th November 1996 00023 // - Added srand48(), seed48(), drand48() implementations 00024 // for Windows/NT: 6th March 1997 00025 // - setSeed(), setSeeds() now have default dummy argument 00026 // set to zero: 11th July 1997 00027 // E.Tcherniaev - Porting on KCC compiler: 2nd Feb 1998 00028 // G.Cosmo - Private copy constructor and operator=: 26th Feb 1998 00029 // J.Marraffino - Added stream operators and related constructor. 00030 // Added automatic seed selection from seed table and 00031 // engine counter: 16th Feb 1998 00032 // E.Tcherniaev - Removed #ifdef for prototypes for drand48(), srand48() 00033 // and seed48(); 00034 // - More accurate code for drand48() on NT base on 00035 // a code extracted from GNU C Library 2.1.3: 8th Nov 2000 00036 // E.Tcherniaev - prototypes for drand48(), srand48() and seed48() have 00037 // been moved to DRand48Engine.cc: 21 Feb 2002 00038 // ======================================================================= 00039 00040 #ifndef DRand48Engine_h 00041 #define DRand48Engine_h 1 00042 00043 #include "CLHEP/Random/RandomEngine.h" 00044 00049 class DRand48Engine : public HepRandomEngine { 00050 00051 public: 00052 00053 DRand48Engine(HepStd::istream& is); 00054 DRand48Engine(); 00055 DRand48Engine(long seed); 00056 DRand48Engine(int rowIndex, int colIndex); 00057 virtual ~DRand48Engine(); 00058 // Constructors and destructor 00059 00060 double flat(); 00061 // It returns a pseudo random number between 0 and 1, 00062 // according to the standard stdlib random function drand48() 00063 // but excluding the end points. 00064 00065 void flatArray (const int size, double* vect); 00066 // Fills the array "vect" of specified size with flat random values. 00067 00068 void setSeed(long seed, int dum=0); 00069 // Sets the state of the algorithm according to seed. 00070 00071 void setSeeds(const long * seeds, int dum=0); 00072 // Sets the state of the algorithm according to the zero terminated 00073 // array of seeds. Only the first seed is used. 00074 00075 void saveStatus( const char filename[] = "DRand48.conf" ) const; 00076 // Saves on file DRand48.conf the current engine status. 00077 00078 void restoreStatus( const char filename[] = "DRand48.conf" ); 00079 // Reads from file DRand48.conf the last saved engine status 00080 // and restores it. 00081 00082 void showStatus() const; 00083 // Dumps the engine status on the screen. 00084 00085 friend HepStd::ostream& operator<< (HepStd::ostream& os, const DRand48Engine& e); 00086 friend HepStd::istream& operator>> (HepStd::istream& is, DRand48Engine& e); 00087 00088 private: 00089 00090 static int numEngines; 00091 static int maxIndex; 00092 00093 DRand48Engine(const DRand48Engine &p); 00094 DRand48Engine & operator = (const DRand48Engine &p); 00095 // Private copy constructor and assignment operator. 00096 00097 }; 00098 00099 #endif