XORShift.h

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/*
 * University of Illinois Open Source License
 * Copyright 2011-2018 Luthey-Schulten Group,
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 * Developed by: Luthey-Schulten Group
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 * Author(s): Elijah Roberts
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#ifndef LM_RNG_XORSHIFT_H_
#define LM_RNG_XORSHIFT_H_
 
#include "core/Types.h"
#include "rng/RandomGenerator.h"
 
namespace lm {
namespace rng {

class XORShift: public RandomGenerator
{
public:
    XORShift(uint32_t seedTop, uint32_t seedBottom);
    virtual ~XORShift() {}

    virtual uint32_t getRandom();
    virtual double getRandomDouble();
    virtual double getExpRandomDouble();
    virtual double getNormRandomDouble();
    
    virtual void getRandomDoubles(double * rngs, int numberRNGs);
    virtual void getExpRandomDoubles(double * rngs, int numberRNGs);
    virtual void getNormRandomDoubles(double * rngs, int numberRNGs);
 
 
protected:
    unsigned long long state;
    bool isNextGaussianValid;
    double nextGaussian;
};
 
}
}
 
#endif