mt.h

 
#ifndef METRICS_MT_H
#define METRICS_MT_H

class MersenneTwister
{
public:
    MersenneTwister(void);
    ~MersenneTwister(void);
 
    double random(void) { return genrand_real1(); }
    void print(void);
 
    void init_genrand(unsigned long s);
    void init_by_array(unsigned long* init_key, int key_length);
 
    unsigned long genrand_int32(void);
    long genrand_int31(void);
    double genrand_real1(void);
    double genrand_real2(void);
    double genrand_real3(void);
    double genrand_res53(void);
 
private:
    static const int N                    = 624;
    static const int M                    = 397;
    // constant vector a
    static const unsigned long MATRIX_A   = 0x9908b0dfUL;
    // most significant w-r bits
    static const unsigned long UPPER_MASK = 0x80000000UL;
    // least significant r bits
    static const unsigned long LOWER_MASK = 0x7fffffffUL;
 
    unsigned long* mt_;                  // the state vector
    int mti_;                            // mti == N+1 means mt not initialized
 
    unsigned long* init_key_;            // Storage for the seed vector
    int key_length_;                     // Seed vector length
    unsigned long s_;                    // Seed integer
    bool seeded_by_array_;               // Seeded by an array
    bool seeded_by_int_;                 // Seeded by an integer
};
 
#endif // METRICS_MT_H