double well_double(well *rng) {
unsigned int *const state = rng->state;
const unsigned int state_n = rng->state_n;
const unsigned int z1 = WELL_IDEN(state[state_n]) ^ WELL_MAT3POS(8, state[(state_n + 3) & 0x0000001fUL]);
const unsigned int z2 = WELL_MAT3NEG(-19, state[(state_n+24) & 0x0000001fUL]) ^ WELL_MAT3NEG(-14, state[(state_n + 10) & 0x0000001fUL]);
state[state_n] = z1 ^ z2;
state[(state_n + 31) & 0x0000001fUL] = WELL_MAT3NEG(-11, (state[(state_n + 31) & 0x0000001fUL])) ^ WELL_MAT3NEG(-7, z1) ^ WELL_MAT3NEG(-13, z2);
rng->state_n = (state_n + 31) & 0x0000001fUL;
return ((double)state[rng->state_n] * 2.32830643653869628906e-10);
}
double well1024_unif_rand(well1024 *prng)
{
unsigned int *state, state_n, z0, z1, z2;
state = prng->state;
state_n = prng->state_n;
z0 = state[(state_n + 31) & 0x0000001FUL];
z1 = state[state_n] ^ WELL_MAT3POS(8, state[(state_n + 3) & 0x0000001FUL]);
z2 = WELL_MAT3NEG(-19, state[(state_n + 24) & 0x0000001FUL]) ^
WELL_MAT3NEG(-14, state[(state_n + 10) & 0x0000001FUL]);
state[state_n] = z1 ^ z2;
state[(state_n + 31) & 0x0000001FUL] = WELL_MAT3NEG(-11, z0) ^
WELL_MAT3NEG( -7, z1) ^
WELL_MAT3NEG(-13, z2);
prng->state_n = (state_n + 31) & 0x0000001FUL;
return ((double) state[prng->state_n] * 2.32830643653869628906E-10);
}
