/*
* Copyright 2007-2013
* Licensed under GNU Lesser General Public License
*
* This file is part of EpochX
*
* EpochX is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* EpochX is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with EpochX. If not, see <http://www.gnu.org/licenses/>.
*
* The latest version is available from: http://www.epochx.org
*/
package org.epochx.random;
import java.io.*;
import org.epochx.RandomSequence;
/**
* The Mersenne twister is a pseudorandom number generator developed in 1997 by
* Makoto Matsumoto and Takuji Nishimura that is based on a matrix linear
* recurrence over a finite binary field <code>F<sub>2</sub></code>. It provides
* for fast generation of very high-quality pseudorandom numbers, having been
* designed specifically to rectify many of the flaws found in older algorithms.
*
* <p>
* This implementation of the Mersenne twister algorithm was written by Sean
* Luke, and released under the following license which takes priority over any
* EpochX license. It has been adapted for use in EpochX.
*
* <h3>License</h3>
*
* Copyright (c) 2003 by Sean Luke. <br>
* Portions copyright (c) 1993 by Michael Lecuyer. <br>
* All rights reserved. <br>
*
* <p>
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* <ul>
* <li>Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* <li>Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* <li>Neither the name of the copyright owners, their employers, nor the names
* of its contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
* </ul>
* <p>
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNERS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
public class MersenneTwisterFast implements Serializable, Cloneable, RandomSequence {
/**
*
*/
private static final long serialVersionUID = 7948923816122472519L;
// Period parameters
private static final int N = 624;
private static final int M = 397;
private static final int MATRIX_A = 0x9908b0df; // private static final *
// constant vector a
private static final int UPPER_MASK = 0x80000000; // most significant w-r
// bits
private static final int LOWER_MASK = 0x7fffffff; // least significant r
// bits
// Tempering parameters
private static final int TEMPERING_MASK_B = 0x9d2c5680;
private static final int TEMPERING_MASK_C = 0xefc60000;
private int mt[]; // the array for the state vector
private int mti; // mti==N+1 means mt[N] is not initialized
private int mag01[];
// a good initial seed (of int size, though stored in a long)
// private static final long GOOD_SEED = 4357;
private double __nextNextGaussian;
private boolean __haveNextNextGaussian;
/*
* We're overriding all internal data, to my knowledge, so this should be
* okay
*/
@Override
public Object clone() throws CloneNotSupportedException {
final MersenneTwisterFast f = (MersenneTwisterFast) (super.clone());
f.mt = mt.clone();
f.mag01 = mag01.clone();
return f;
}
public boolean stateEquals(final Object o) {
if (o == this) {
return true;
}
if ((o == null) || !(o instanceof MersenneTwisterFast)) {
return false;
}
final MersenneTwisterFast other = (MersenneTwisterFast) o;
if (mti != other.mti) {
return false;
}
for (int x = 0; x < mag01.length; x++) {
if (mag01[x] != other.mag01[x]) {
return false;
}
}
for (int x = 0; x < mt.length; x++) {
if (mt[x] != other.mt[x]) {
return false;
}
}
return true;
}
/**
* Reads the entire state of the MersenneTwister RNG from the stream
*
* @param stream input stream
* @throws IOException exception from stream reading
*/
public void readState(final DataInputStream stream) throws IOException {
int len = mt.length;
for (int x = 0; x < len; x++) {
mt[x] = stream.readInt();
}
len = mag01.length;
for (int x = 0; x < len; x++) {
mag01[x] = stream.readInt();
}
mti = stream.readInt();
__nextNextGaussian = stream.readDouble();
__haveNextNextGaussian = stream.readBoolean();
}
/**
* Writes the entire state of the MersenneTwister RNG to the stream
*
* @param stream output stream
* @throws IOException exception from stream reading
*/
public void writeState(final DataOutputStream stream) throws IOException {
int len = mt.length;
for (int x = 0; x < len; x++) {
stream.writeInt(mt[x]);
}
len = mag01.length;
for (int x = 0; x < len; x++) {
stream.writeInt(mag01[x]);
}
stream.writeInt(mti);
stream.writeDouble(__nextNextGaussian);
stream.writeBoolean(__haveNextNextGaussian);
}
/**
* Constructor using the default seed.
*/
public MersenneTwisterFast() {
this(System.currentTimeMillis());
}
/**
* Constructor using a given seed. Though you pass this seed in
* as a long, it's best to make sure it's actually an integer.
*
* @param seed seed
*/
public MersenneTwisterFast(final long seed) {
setSeed(seed);
}
/**
* Constructor using an array of integers as seed.
* Your array must have a non-zero length. Only the first 624 integers
* in the array are used; if the array is shorter than this then
* integers are repeatedly used in a wrap-around fashion.
*
* @param array seed array
*/
public MersenneTwisterFast(final int[] array) {
setSeed(array);
}
/**
* Initialize the pseudo random number generator. Don't
* pass in a long that's bigger than an int (Mersenne Twister
* only uses the first 32 bits for its seed).
*/
@Override
synchronized public void setSeed(final long seed) {
// Due to a bug in java.util.Random clear up to 1.2, we're
// doing our own Gaussian variable.
__haveNextNextGaussian = false;
mt = new int[N];
mag01 = new int[2];
mag01[0] = 0x0;
mag01[1] = MATRIX_A;
mt[0] = (int) (seed);
for (mti = 1; mti < N; mti++) {
mt[mti] = ((1812433253 * (mt[mti - 1] ^ (mt[mti - 1] >>> 30))) + mti);
/* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
/* In the previous versions, MSBs of the seed affect */
/* only MSBs of the array mt[]. */
/* 2002/01/09 modified by Makoto Matsumoto */
mt[mti] &= 0xffffffff;
/* for >32 bit machines */
}
}
/**
* Sets the seed of the MersenneTwister using an array of integers.
* Your array must have a non-zero length. Only the first 624 integers
* in the array are used; if the array is shorter than this then
* integers are repeatedly used in a wrap-around fashion.
*/
synchronized public void setSeed(final int[] array) {
if (array.length == 0) {
throw new IllegalArgumentException("Array length must be greater than zero");
}
int i, j, k;
setSeed(19650218);
i = 1;
j = 0;
k = (N > array.length ? N : array.length);
for (; k != 0; k--) {
mt[i] = (mt[i] ^ ((mt[i - 1] ^ (mt[i - 1] >>> 30)) * 1664525)) + array[j] + j; /*
* non
* linear
*/
mt[i] &= 0xffffffff; /* for WORDSIZE > 32 machines */
i++;
j++;
if (i >= N) {
mt[0] = mt[N - 1];
i = 1;
}
if (j >= array.length) {
j = 0;
}
}
for (k = N - 1; k != 0; k--) {
mt[i] = (mt[i] ^ ((mt[i - 1] ^ (mt[i - 1] >>> 30)) * 1566083941)) - i; /*
* non
* linear
*/
mt[i] &= 0xffffffff; /* for WORDSIZE > 32 machines */
i++;
if (i >= N) {
mt[0] = mt[N - 1];
i = 1;
}
}
mt[0] = 0x80000000; /* MSB is 1; assuring non-zero initial array */
}
@Override
public final int nextInt() {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return y;
}
public final short nextShort() {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return (short) (y >>> 16);
}
public final char nextChar() {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return (char) (y >>> 16);
}
@Override
public final boolean nextBoolean() {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return (y >>> 31) != 0;
}
/**
* This generates a coin flip with a probability <code>probability</code> of
* returning true, else returning false. <code>probability</code> must
* be between 0.0 and 1.0, inclusive. Not as precise a random real
* event as nextBoolean(double), but twice as fast. To explicitly
* use this, remember you may need to cast to float first.
*
* @param probability flip probability
* @return next boolean
*/
public final boolean nextBoolean(final float probability) {
int y;
if ((probability < 0.0f) || (probability > 1.0f)) {
throw new IllegalArgumentException("probability must be between 0.0 and 1.0 inclusive.");
}
if (probability == 0.0f) {
return false; // fix half-open issues
} else if (probability == 1.0f) {
return true; // fix half-open issues
}
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return ((y >>> 8) / ((float) (1 << 24))) < probability;
}
/**
* This generates a coin flip with a probability <code>probability</code> of
* returning true, else returning false. <code>probability</code> must
* be between 0.0 and 1.0, inclusive.
*/
public final boolean nextBoolean(final double probability) {
int y;
int z;
if ((probability < 0.0) || (probability > 1.0)) {
throw new IllegalArgumentException("probability must be between 0.0 and 1.0 inclusive.");
}
if (probability == 0.0) {
return false; // fix half-open issues
} else if (probability == 1.0) {
return true; // fix half-open issues
}
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (z >>> 1) ^ mag01[z & 0x1];
}
for (; kk < (N - 1); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (z >>> 1) ^ mag01[z & 0x1];
}
z = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (z >>> 1) ^ mag01[z & 0x1];
mti = 0;
}
z = mt[mti++];
z ^= z >>> 11; // TEMPERING_SHIFT_U(z)
z ^= (z << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(z)
z ^= (z << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(z)
z ^= (z >>> 18); // TEMPERING_SHIFT_L(z)
/* derived from nextDouble documentation in jdk 1.2 docs, see top */
return (((((long) (y >>> 6)) << 27) + (z >>> 5)) / (double) (1L << 53)) < probability;
}
public final byte nextByte() {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return (byte) (y >>> 24);
}
public final void nextBytes(final byte[] bytes) {
int y;
for (int x = 0; x < bytes.length; x++) {
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
bytes[x] = (byte) (y >>> 24);
}
}
@Override
public final long nextLong() {
int y;
int z;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (z >>> 1) ^ mag01[z & 0x1];
}
for (; kk < (N - 1); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (z >>> 1) ^ mag01[z & 0x1];
}
z = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (z >>> 1) ^ mag01[z & 0x1];
mti = 0;
}
z = mt[mti++];
z ^= z >>> 11; // TEMPERING_SHIFT_U(z)
z ^= (z << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(z)
z ^= (z << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(z)
z ^= (z >>> 18); // TEMPERING_SHIFT_L(z)
return (((long) y) << 32) + z;
}
/**
* Returns a long drawn uniformly from 0 to n-1. Suffice it to say,
* n must be > 0, or an IllegalArgumentException is raised.
*
* @param n max long
* @return next long
*/
@Override
public final long nextLong(final long n) {
if (n <= 0) {
throw new IllegalArgumentException("n must be positive");
}
long bits, val;
do {
int y;
int z;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (z >>> 1) ^ mag01[z & 0x1];
}
for (; kk < (N - 1); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (z >>> 1) ^ mag01[z & 0x1];
}
z = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (z >>> 1) ^ mag01[z & 0x1];
mti = 0;
}
z = mt[mti++];
z ^= z >>> 11; // TEMPERING_SHIFT_U(z)
z ^= (z << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(z)
z ^= (z << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(z)
z ^= (z >>> 18); // TEMPERING_SHIFT_L(z)
bits = (((((long) y) << 32) + z) >>> 1);
val = bits % n;
} while (((bits - val) + (n - 1)) < 0);
return val;
}
/**
* Returns a random double in the half-open range from [0.0,1.0). Thus 0.0
* is a valid
* result but 1.0 is not.
*/
@Override
public final double nextDouble() {
int y;
int z;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (z >>> 1) ^ mag01[z & 0x1];
}
for (; kk < (N - 1); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (z >>> 1) ^ mag01[z & 0x1];
}
z = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (z >>> 1) ^ mag01[z & 0x1];
mti = 0;
}
z = mt[mti++];
z ^= z >>> 11; // TEMPERING_SHIFT_U(z)
z ^= (z << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(z)
z ^= (z << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(z)
z ^= (z >>> 18); // TEMPERING_SHIFT_L(z)
/* derived from nextDouble documentation in jdk 1.2 docs, see top */
return ((((long) (y >>> 6)) << 27) + (z >>> 5)) / (double) (1L << 53);
}
public final double nextGaussian() {
if (__haveNextNextGaussian) {
__haveNextNextGaussian = false;
return __nextNextGaussian;
} else {
double v1, v2, s;
do {
int y;
int z;
int a;
int b;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly
// faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly
// faster
for (kk = 0; kk < (N - M); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (z >>> 1) ^ mag01[z & 0x1];
}
for (; kk < (N - 1); kk++) {
z = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (z >>> 1) ^ mag01[z & 0x1];
}
z = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (z >>> 1) ^ mag01[z & 0x1];
mti = 0;
}
z = mt[mti++];
z ^= z >>> 11; // TEMPERING_SHIFT_U(z)
z ^= (z << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(z)
z ^= (z << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(z)
z ^= (z >>> 18); // TEMPERING_SHIFT_L(z)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly
// faster
for (kk = 0; kk < (N - M); kk++) {
a = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (a >>> 1) ^ mag01[a & 0x1];
}
for (; kk < (N - 1); kk++) {
a = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (a >>> 1) ^ mag01[a & 0x1];
}
a = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (a >>> 1) ^ mag01[a & 0x1];
mti = 0;
}
a = mt[mti++];
a ^= a >>> 11; // TEMPERING_SHIFT_U(a)
a ^= (a << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(a)
a ^= (a << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(a)
a ^= (a >>> 18); // TEMPERING_SHIFT_L(a)
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly
// faster
for (kk = 0; kk < (N - M); kk++) {
b = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (b >>> 1) ^ mag01[b & 0x1];
}
for (; kk < (N - 1); kk++) {
b = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (b >>> 1) ^ mag01[b & 0x1];
}
b = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (b >>> 1) ^ mag01[b & 0x1];
mti = 0;
}
b = mt[mti++];
b ^= b >>> 11; // TEMPERING_SHIFT_U(b)
b ^= (b << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(b)
b ^= (b << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(b)
b ^= (b >>> 18); // TEMPERING_SHIFT_L(b)
/*
* derived from nextDouble documentation in jdk 1.2 docs, see
* top
*/
v1 = (2 * (((((long) (y >>> 6)) << 27) + (z >>> 5)) / (double) (1L << 53))) - 1;
v2 = (2 * (((((long) (a >>> 6)) << 27) + (b >>> 5)) / (double) (1L << 53))) - 1;
s = (v1 * v1) + (v2 * v2);
} while ((s >= 1) || (s == 0));
final double multiplier = /* Strict */Math.sqrt((-2 * /* Strict */Math.log(s)) / s);
__nextNextGaussian = v2 * multiplier;
__haveNextNextGaussian = true;
return v1 * multiplier;
}
}
/**
* Returns a random float in the half-open range from [0.0f,1.0f). Thus 0.0f
* is a valid
* result but 1.0f is not.
*
* @return next float
*/
public final float nextFloat() {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return (y >>> 8) / ((float) (1 << 24));
}
/**
* Returns an integer drawn uniformly from 0 to n-1. Suffice it to say,
* n must be > 0, or an IllegalArgumentException is raised.
*/
@Override
public final int nextInt(final int n) {
if (n <= 0) {
throw new IllegalArgumentException("n must be positive");
} else if (n == 1) {
// Will always be the value 0.
return 0;
}
if ((n & -n) == n) // i.e., n is a power of 2
{
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
return (int) ((n * (long) (y >>> 1)) >> 31);
}
int bits, val;
do {
int y;
if (mti >= N) // generate N words at one time
{
int kk;
final int[] mt = this.mt; // locals are slightly faster
final int[] mag01 = this.mag01; // locals are slightly faster
for (kk = 0; kk < (N - M); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
}
for (; kk < (N - 1); kk++) {
y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
}
y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];
mti = 0;
}
y = mt[mti++];
y ^= y >>> 11; // TEMPERING_SHIFT_U(y)
y ^= (y << 7) & TEMPERING_MASK_B; // TEMPERING_SHIFT_S(y)
y ^= (y << 15) & TEMPERING_MASK_C; // TEMPERING_SHIFT_T(y)
y ^= (y >>> 18); // TEMPERING_SHIFT_L(y)
bits = (y >>> 1);
val = bits % n;
} while (((bits - val) + (n - 1)) < 0);
return val;
}
}