Ranlux64Engine

The algorithm for this random engine has been taken from the notes of a double-precision ranlux implementation by Martin Luscher, dated November 1997.

Like the previous Ranlux generator, this one also has "luxury" levels, determining how many pseudo-random numbers are discarded for every twelve values used. Three levels are given, with the note that Luscher himself advocates only the highest two levels for this engine.

level 0 (p=109): Throw away 109 values for every 12 used

level 1 (p=202): Throw away 202 values for every 12 used (default)

level 2 (p=397): Throw away 397 values for every 12 used

The initialization is carried out using a Multiplicative Congruential generator using formula constants of L'Ecuyer as described in "F.James, Comp. Phys. Comm. 60 (1990) 329-344".

Author

Ken Smith

Declaration

#include "CLHEP/Random/Ranlux64Engine.h"

class Ranlux64Engine : public HepRandomEngine

Public Member Functions

Constructors: Ranlux64Engine(); Ranlux64Engine(std::istream& is); Ranlux64Engine(long seed, HepInt lux = 1); Ranlux64Engine(HepInt rowIndex, HepInt colIndex, HepInt lux)
Copy constructor: Ranlux64Engine(const Ranlux64Engine &p)
Destructor: virtual ~Ranlux64Engine()
=: Ranlux64Engine & operator = (const Ranlux64Engine &p); Overloaded assignment operator, to retrieve the engine status.
flat: HepDouble flat(); It returns a pseudo random number between 0 and 1, excluding the end points.
flatArray: void flatArray (const HepInt size, HepDouble* vect); Fills the array vect of specified size with flat random values.
getLuxury: HepInt getLuxury() const; Gets the luxury level.
restoreStatus: void restoreStatus(const char filename[] = "Ranlux64.conf"); Reads from named file the last saved engine status and restores it
saveStatus: void saveStatus(const char filename[] = "Ranlux64.conf") const; Saves in named file the current engine status.
setSeed: void setSeed(long seed, HepInt lux=1); Sets the state of the algorithm according to seed.
setSeeds: void setSeeds(const long * seeds, HepInt lux=1); Sets the state of the algorithm according to the zero terminated array of seeds. Only the first seed is used.
showStatus: void showStatus() const; Dumps the engine status on the screen.

Non-Member Functions

<<: std::ostream & operator<< (std::ostream & os, const Ranlux64Engine & e); Output to a stream.
>>: std::istream & operator>> (std::istream & is, Ranlux64Engine & e); Input from a stream.

Example

CLHEP/test/testRandom.cc