#include <limits> /* std::numeric_limits */
#include "igs_math_random.h"
//using igs::math::random;
igs::math::random::random() : seed_(1) {}
/* 乱数種 seed(0〜std::numeric_limits<long>::max()) */
void igs::math::random::seed(unsigned long seed) { this->seed_ = seed; }
unsigned long
igs::math::random::seed(void) const { return this->seed_; }
/* 乱数生成 0〜std::numeric_limits<long>::max() */
long igs::math::random::next(void)
{
this->seed_ = this->seed_ * 1103515245UL + 12345UL;
/* 0x41C64E6D + 0x3039 */
return static_cast<long>((this->seed_) %
(static_cast<unsigned long>(std::numeric_limits<long>::max()) + 1UL));
// /* (this->seed_/ 65536)%32768 */
// return (this->seed_/0x10000)%0x8000;
}
double
igs::math::random::next_d(void)
{ /* 0 ... 1 */
return static_cast<double>(this->next()) /
static_cast<double>(std::numeric_limits<long>::max());
}