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#ifndef TINYMT64_H
#define TINYMT64_H
/**
* @file tinymt64.h
*
* @brief Tiny Mersenne Twister only 127 bit internal state
*
* @author Mutsuo Saito (Hiroshima University)
* @author Makoto Matsumoto (The University of Tokyo)
*
* Copyright (C) 2011 Mutsuo Saito, Makoto Matsumoto,
* Hiroshima University and The University of Tokyo.
* All rights reserved.
*
* The 3-clause BSD License is applied to this software, see
* LICENSE.txt
*/
#include <stdint.h>
#include <inttypes.h>
#define TINYMT64_MEXP 127
#define TINYMT64_SH0 12
#define TINYMT64_SH1 11
#define TINYMT64_SH8 8
#define TINYMT64_MASK UINT64_C(0x7fffffffffffffff)
#define TINYMT64_MUL (1.0 / 18446744073709551616.0)
/*
* tinymt64 internal state vector and parameters
*/
struct TINYMT64_T {
uint64_t status[2];
uint32_t mat1;
uint32_t mat2;
uint64_t tmat;
};
typedef struct TINYMT64_T tinymt64_t;
void tinymt64_init(tinymt64_t * random, uint64_t seed);
void tinymt64_init_by_array(tinymt64_t * random, const uint64_t init_key[],
int key_length);
#if defined(__GNUC__)
/**
* This function always returns 127
* @param random not used
* @return always 127
*/
inline static int tinymt64_get_mexp(
tinymt64_t * random __attribute__((unused))) {
return TINYMT64_MEXP;
}
#else
inline static int tinymt64_get_mexp(tinymt64_t * random) {
return TINYMT64_MEXP;
}
#endif
/**
* This function changes internal state of tinymt64.
* Users should not call this function directly.
* @param random tinymt internal status
*/
inline static void tinymt64_next_state(tinymt64_t * random) {
uint64_t x;
random->status[0] &= TINYMT64_MASK;
x = random->status[0] ^ random->status[1];
x ^= x << TINYMT64_SH0;
x ^= x >> 32;
x ^= x << 32;
x ^= x << TINYMT64_SH1;
random->status[0] = random->status[1];
random->status[1] = x;
random->status[0] ^= -((int64_t)(x & 1)) & random->mat1;
random->status[1] ^= -((int64_t)(x & 1)) & (((uint64_t)random->mat2) << 32);
}
/**
* This function outputs 64-bit unsigned integer from internal state.
* Users should not call this function directly.
* @param random tinymt internal status
* @return 64-bit unsigned pseudorandom number
*/
inline static uint64_t tinymt64_temper(tinymt64_t * random) {
uint64_t x;
#if defined(LINEARITY_CHECK)
x = random->status[0] ^ random->status[1];
#else
x = random->status[0] + random->status[1];
#endif
x ^= random->status[0] >> TINYMT64_SH8;
x ^= -((int64_t)(x & 1)) & random->tmat;
return x;
}
/**
* This function outputs floating point number from internal state.
* Users should not call this function directly.
* @param random tinymt internal status
* @return floating point number r (1.0 <= r < 2.0)
*/
inline static double tinymt64_temper_conv(tinymt64_t * random) {
uint64_t x;
union {
uint64_t u;
double d;
} conv;
#if defined(LINEARITY_CHECK)
x = random->status[0] ^ random->status[1];
#else
x = random->status[0] + random->status[1];
#endif
x ^= random->status[0] >> TINYMT64_SH8;
conv.u = ((x ^ (-((int64_t)(x & 1)) & random->tmat)) >> 12)
| UINT64_C(0x3ff0000000000000);
return conv.d;
}
/**
* This function outputs floating point number from internal state.
* Users should not call this function directly.
* @param random tinymt internal status
* @return floating point number r (1.0 < r < 2.0)
*/
inline static double tinymt64_temper_conv_open(tinymt64_t * random) {
uint64_t x;
union {
uint64_t u;
double d;
} conv;
#if defined(LINEARITY_CHECK)
x = random->status[0] ^ random->status[1];
#else
x = random->status[0] + random->status[1];
#endif
x ^= random->status[0] >> TINYMT64_SH8;
conv.u = ((x ^ (-((int64_t)(x & 1)) & random->tmat)) >> 12)
| UINT64_C(0x3ff0000000000001);
return conv.d;
}
/**
* This function outputs 64-bit unsigned integer from internal state.
* @param random tinymt internal status
* @return 64-bit unsigned integer r (0 <= r < 2^64)
*/
inline static uint64_t tinymt64_generate_uint64(tinymt64_t * random) {
tinymt64_next_state(random);
return tinymt64_temper(random);
}
/**
* This function outputs floating point number from internal state.
* This function is implemented using multiplying by 1 / 2^64.
* @param random tinymt internal status
* @return floating point number r (0.0 <= r < 1.0)
*/
inline static double tinymt64_generate_double(tinymt64_t * random) {
tinymt64_next_state(random);
return tinymt64_temper(random) * TINYMT64_MUL;
}
/**
* This function outputs floating point number from internal state.
* This function is implemented using union trick.
* @param random tinymt internal status
* @return floating point number r (0.0 <= r < 1.0)
*/
inline static double tinymt64_generate_double01(tinymt64_t * random) {
tinymt64_next_state(random);
return tinymt64_temper_conv(random) - 1.0;
}
/**
* This function outputs floating point number from internal state.
* This function is implemented using union trick.
* @param random tinymt internal status
* @return floating point number r (1.0 <= r < 2.0)
*/
inline static double tinymt64_generate_double12(tinymt64_t * random) {
tinymt64_next_state(random);
return tinymt64_temper_conv(random);
}
/**
* This function outputs floating point number from internal state.
* This function is implemented using union trick.
* @param random tinymt internal status
* @return floating point number r (0.0 < r <= 1.0)
*/
inline static double tinymt64_generate_doubleOC(tinymt64_t * random) {
tinymt64_next_state(random);
return 2.0 - tinymt64_temper_conv(random);
}
/**
* This function outputs floating point number from internal state.
* This function is implemented using union trick.
* @param random tinymt internal status
* @return floating point number r (0.0 < r < 1.0)
*/
inline static double tinymt64_generate_doubleOO(tinymt64_t * random) {
tinymt64_next_state(random);
return tinymt64_temper_conv_open(random) - 1.0;
}
#endif
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