Utility::Rng Class Reference

The Mersenne Twister http://www.math.keio.ac.jp/~matumoto/emt.html. More...

List of all members.

Public Member Functions
	Rng (unsigned long seed)
unsigned long	Get ()
Private Attributes
int	m_value
unsigned long	m_tmp [TWIST_LEN]

---

Detailed Description

The Mersenne Twister http://www.math.keio.ac.jp/~matumoto/emt.html.

Definition at line 57 of file Utility.h.

---

Constructor & Destructor Documentation

Utility::Rng::Rng

(

unsigned long

seed

)

Definition at line 1069 of file Utility.cpp.

References m_tmp, and TWIST_LEN.

                                  : m_value( 0 )
{
        m_tmp[0] = seed & 0xffffffffUL;
        for (int i = 1; i < TWIST_LEN; i++)
        {
                m_tmp[i] = (1812433253UL * (m_tmp[i - 1] ^ (m_tmp[i - 1] >> 30)) + i);
        }
}

---

Member Function Documentation

unsigned long Utility::Rng::Get

(

)

Definition at line 1079 of file Utility.cpp.

References m_tmp, m_value, MAGIC_TWIST, TWIST, TWIST_IA, TWIST_IB, and TWIST_LEN.

Referenced by Utility::Rnd().

{
        unsigned long val = m_tmp[m_value];
        ++m_value;
        if (m_value == TWIST_LEN)
        {
                for (int i = 0; i < TWIST_IB; ++i)
                {
                        unsigned long s = TWIST(m_tmp, i, i + 1);
                        m_tmp[i] = m_tmp[i + TWIST_IA] ^ (s >> 1) ^ MAGIC_TWIST(s);
                }
                {
                        for (int i = 0; i < TWIST_LEN - 1; ++i)
                        {
                                unsigned long s = TWIST(m_tmp, i, i + 1);
                                m_tmp[i] = m_tmp[i - TWIST_IB] ^ (s >> 1) ^ MAGIC_TWIST(s);
                        }
                }
                unsigned long s = TWIST(m_tmp, TWIST_LEN - 1, 0);
                m_tmp[TWIST_LEN - 1] = m_tmp[TWIST_IA - 1] ^ (s >> 1) ^ MAGIC_TWIST(s);

                m_value = 0;
        }
        return val;
}

---

Member Data Documentation

int Utility::Rng::m_value [private]

Definition at line 64 of file Utility.h.

Referenced by Get().

unsigned long Utility::Rng::m_tmp[TWIST_LEN] [private]

Definition at line 65 of file Utility.h.

Referenced by Get(), and Rng().

---

The documentation for this class was generated from the following files:

• Utility.h
• Utility.cpp