public double getNextDouble(rk_state state)
{
/* shifts : 67108864 = 0x4000000, 9007199254740992 = 0x20000000000000 */
ulong a = getNextUInt64(state) >> 5;
ulong b = getNextUInt64(state) >> 6;
return((a * 67108864.0 + b) / 9007199254740992.0);
}
public void Seed(ulong?seedValue, rk_state state)
{
if (seedValue.HasValue)
{
rnd = new Random((int)seedValue.Value);
}
else
{
rnd = new Random();
}
return;
}
public ulong getNextUInt64(rk_state state)
{
/* Magic Mersenne Twister constants */
const int N = 624;
const int M = 397;
const ulong MATRIX_A = 0x9908b0dfUL;
const ulong UPPER_MASK = 0x80000000UL;
const ulong LOWER_MASK = 0x7fffffffUL;
ulong y;
if (state.pos == RK_STATE_LEN)
{
int i;
long ly;
ulong uy;
for (i = 0; i < N - M; i++)
{
y = (key[i] & UPPER_MASK) | (key[i + 1] & LOWER_MASK);
ly = (long)(y & 1);
uy = (ulong)-ly;
key[i] = key[i + M] ^ (y >> 1) ^ (uy & MATRIX_A);
}
for (; i < N - 1; i++)
{
y = (key[i] & UPPER_MASK) | (key[i + 1] & LOWER_MASK);
ly = (long)(y & 1);
uy = (ulong)-ly;
key[i] = key[i + (M - N)] ^ (y >> 1) ^ (uy & MATRIX_A);
}
y = (key[N - 1] & UPPER_MASK) | (key[0] & LOWER_MASK);
ly = (long)(y & 1);
uy = (ulong)-ly;
key[N - 1] = key[M - 1] ^ (y >> 1) ^ (uy & MATRIX_A);
state.pos = 0;
}
y = key[state.pos++];
/* Tempering */
y ^= (y >> 11);
y ^= (y << 7) & 0x9d2c5680UL;
y ^= (y << 15) & 0xefc60000UL;
y ^= (y >> 18);
return(y);
}
public void Seed(ulong?inseed, rk_state state)
{
uint pos;
if (!inseed.HasValue)
{
inseed = (ulong)DateTime.Now.Ticks;
}
ulong seed = inseed.Value;
seed &= 0xffffffffUL;
/* Knuth's PRNG as used in the Mersenne Twister reference implementation */
for (pos = 0; pos < RK_STATE_LEN; pos++)
{
key[pos] = seed;
seed = (1812433253UL * (seed ^ (seed >> 30)) + pos + 1) & 0xffffffffUL;
}
state.pos = RK_STATE_LEN;
state.gauss = 0;
state.has_gauss = false;
state.has_binomial = false;
}
public ulong getNextUInt64(rk_state state)
{
ulong randomValue = (ulong)rnd.Next() << 32 + rnd.Next();
return(randomValue);
}
public double getNextDouble(rk_state state)
{
return(rnd.NextDouble());
}
