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source: branches/OKBJavaConnector/ECJClient/src/ec/util/MersenneTwister.java @ 9449

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added ecj and custom statistics to communicate with the okb services #1441

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1package ec.util;
2
3import java.io.*;
4
5/**
6 * <h3>MersenneTwister and MersenneTwisterFast</h3>
7 * <p><b>Version 16</b>, based on version MT199937(99/10/29)
8 * of the Mersenne Twister algorithm found at
9 * <a href="http://www.math.keio.ac.jp/matumoto/emt.html">
10 * The Mersenne Twister Home Page</a>, with the initialization
11 * improved using the new 2002/1/26 initialization algorithm
12 * By Sean Luke, October 2004.
13 *
14 * <p><b>MersenneTwister</b> is a drop-in subclass replacement
15 * for java.util.Random.  It is properly synchronized and
16 * can be used in a multithreaded environment.  On modern VMs such
17 * as HotSpot, it is approximately 1/3 slower than java.util.Random.
18 *
19 * <p><b>MersenneTwisterFast</b> is not a subclass of java.util.Random.  It has
20 * the same public methods as Random does, however, and it is
21 * algorithmically identical to MersenneTwister.  MersenneTwisterFast
22 * has hard-code inlined all of its methods directly, and made all of them
23 * final (well, the ones of consequence anyway).  Further, these
24 * methods are <i>not</i> synchronized, so the same MersenneTwisterFast
25 * instance cannot be shared by multiple threads.  But all this helps
26 * MersenneTwisterFast achieve well over twice the speed of MersenneTwister.
27 * java.util.Random is about 1/3 slower than MersenneTwisterFast.
28 *
29 * <h3>About the Mersenne Twister</h3>
30 * <p>This is a Java version of the C-program for MT19937: Integer version.
31 * The MT19937 algorithm was created by Makoto Matsumoto and Takuji Nishimura,
32 * who ask: "When you use this, send an email to: matumoto@math.keio.ac.jp
33 * with an appropriate reference to your work".  Indicate that this
34 * is a translation of their algorithm into Java.
35 *
36 * <p><b>Reference. </b>
37 * Makato Matsumoto and Takuji Nishimura,
38 * "Mersenne Twister: A 623-Dimensionally Equidistributed Uniform
39 * Pseudo-Random Number Generator",
40 * <i>ACM Transactions on Modeling and Computer Simulation,</i>
41 * Vol. 8, No. 1, January 1998, pp 3--30.
42 *
43 * <h3>About this Version</h3>
44 *
45 * <p><b>Changes Since V15:</b> Added serialVersionUID to quiet compiler warnings
46 * from Sun's overly verbose compilers as of JDK 1.5.
47 *
48 * <p><b>Changes Since V14:</b> made strictfp, with StrictMath.log and StrictMath.sqrt
49 * in nextGaussian instead of Math.log and Math.sqrt.  This is largely just to be safe,
50 * as it presently makes no difference in the speed, correctness, or results of the
51 * algorithm.
52 *
53 * <p><b>Changes Since V13:</b> clone() method CloneNotSupportedException removed. 
54 *
55 * <p><b>Changes Since V12:</b> clone() method added.
56 *
57 * <p><b>Changes Since V11:</b> stateEquals(...) method added.  MersenneTwisterFast
58 * is equal to other MersenneTwisterFasts with identical state; likewise
59 * MersenneTwister is equal to other MersenneTwister with identical state.
60 * This isn't equals(...) because that requires a contract of immutability
61 * to compare by value.
62 *
63 * <p><b>Changes Since V10:</b> A documentation error suggested that
64 * setSeed(int[]) required an int[] array 624 long.  In fact, the array
65 * can be any non-zero length.  The new version also checks for this fact.
66 *
67 * <p><b>Changes Since V9:</b> readState(stream) and writeState(stream)
68 * provided.
69 *
70 * <p><b>Changes Since V8:</b> setSeed(int) was only using the first 28 bits
71 * of the seed; it should have been 32 bits.  For small-number seeds the
72 * behavior is identical.
73 *
74 * <p><b>Changes Since V7:</b> A documentation error in MersenneTwisterFast
75 * (but not MersenneTwister) stated that nextDouble selects uniformly from
76 * the full-open interval [0,1].  It does not.  nextDouble's contract is
77 * identical across MersenneTwisterFast, MersenneTwister, and java.util.Random,
78 * namely, selection in the half-open interval [0,1).  That is, 1.0 should
79 * not be returned.  A similar contract exists in nextFloat.
80 *
81 * <p><b>Changes Since V6:</b> License has changed from LGPL to BSD.
82 * New timing information to compare against
83 * java.util.Random.  Recent versions of HotSpot have helped Random increase
84 * in speed to the point where it is faster than MersenneTwister but slower
85 * than MersenneTwisterFast (which should be the case, as it's a less complex
86 * algorithm but is synchronized).
87 *
88 * <p><b>Changes Since V5:</b> New empty constructor made to work the same
89 * as java.util.Random -- namely, it seeds based on the current time in
90 * milliseconds.
91 *
92 * <p><b>Changes Since V4:</b> New initialization algorithms.  See
93 * (see <a href="http://www.math.keio.ac.jp/matumoto/MT2002/emt19937ar.html"</a>
94 * http://www.math.keio.ac.jp/matumoto/MT2002/emt19937ar.html</a>)
95 *
96 * <p>The MersenneTwister code is based on standard MT19937 C/C++
97 * code by Takuji Nishimura,
98 * with suggestions from Topher Cooper and Marc Rieffel, July 1997.
99 * The code was originally translated into Java by Michael Lecuyer,
100 * January 1999, and the original code is Copyright (c) 1999 by Michael Lecuyer.
101 *
102 * <h3>Java notes</h3>
103 *
104 * <p>This implementation implements the bug fixes made
105 * in Java 1.2's version of Random, which means it can be used with
106 * earlier versions of Java.  See
107 * <a href="http://www.javasoft.com/products/jdk/1.2/docs/api/java/util/Random.html">
108 * the JDK 1.2 java.util.Random documentation</a> for further documentation
109 * on the random-number generation contracts made.  Additionally, there's
110 * an undocumented bug in the JDK java.util.Random.nextBytes() method,
111 * which this code fixes.
112 *
113 * <p> Just like java.util.Random, this
114 * generator accepts a long seed but doesn't use all of it.  java.util.Random
115 * uses 48 bits.  The Mersenne Twister instead uses 32 bits (int size).
116 * So it's best if your seed does not exceed the int range.
117 *
118 * <p>MersenneTwister can be used reliably
119 * on JDK version 1.1.5 or above.  Earlier Java versions have serious bugs in
120 * java.util.Random; only MersenneTwisterFast (and not MersenneTwister nor
121 * java.util.Random) should be used with them.
122 *
123 * <h3>License</h3>
124 *
125 * Copyright (c) 2003 by Sean Luke. <br>
126 * Portions copyright (c) 1993 by Michael Lecuyer. <br>
127 * All rights reserved. <br>
128 *
129 * <p>Redistribution and use in source and binary forms, with or without
130 * modification, are permitted provided that the following conditions are met:
131 * <ul>
132 * <li> Redistributions of source code must retain the above copyright notice,
133 * this list of conditions and the following disclaimer.
134 * <li> Redistributions in binary form must reproduce the above copyright notice,
135 * this list of conditions and the following disclaimer in the documentation
136 * and/or other materials provided with the distribution.
137 * <li> Neither the name of the copyright owners, their employers, nor the
138 * names of its contributors may be used to endorse or promote products
139 * derived from this software without specific prior written permission.
140 * </ul>
141 * <p>THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
142 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
143 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
144 * DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNERS OR CONTRIBUTORS BE
145 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
146 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
147 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
148 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
149 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
150 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
151 * POSSIBILITY OF SUCH DAMAGE.
152 *
153 @version 16
154*/
155
156public strictfp class MersenneTwister extends java.util.Random implements Serializable, Cloneable
157    {
158    // Serialization
159    private static final long serialVersionUID = -4035832775130174188L;  // locked as of Version 15
160
161    // Period parameters
162    private static final int N = 624;
163    private static final int M = 397;
164    private static final int MATRIX_A = 0x9908b0df;   //    private static final * constant vector a
165    private static final int UPPER_MASK = 0x80000000; // most significant w-r bits
166    private static final int LOWER_MASK = 0x7fffffff; // least significant r bits
167
168    // Tempering parameters
169    private static final int TEMPERING_MASK_B = 0x9d2c5680;
170    private static final int TEMPERING_MASK_C = 0xefc60000;
171   
172    private int mt[]; // the array for the state vector
173    private int mti; // mti==N+1 means mt[N] is not initialized
174    private int mag01[];
175   
176    // a good initial seed (of int size, though stored in a long)
177    //private static final long GOOD_SEED = 4357;
178
179    /* implemented here because there's a bug in Random's implementation
180       of the Gaussian code (divide by zero, and log(0), ugh!), yet its
181       gaussian variables are private so we can't access them here.  :-( */
182
183    private double __nextNextGaussian;
184    private boolean __haveNextNextGaussian;
185
186    /* We're overriding all internal data, to my knowledge, so this should be okay */
187    public Object clone()
188        {
189        try
190            {
191            MersenneTwister f = (MersenneTwister)(super.clone());
192            f.mt = (int[])(mt.clone());
193            f.mag01 = (int[])(mag01.clone());
194            return f;
195            }
196        catch (CloneNotSupportedException e) { throw new InternalError(); } // should never happen
197        }
198
199    public boolean stateEquals(Object o)
200        {
201        if (o==this) return true;
202        if (o == null || !(o instanceof MersenneTwister))
203            return false;
204        MersenneTwister other = (MersenneTwister) o;
205        if (mti != other.mti) return false;
206        for(int x=0;x<mag01.length;x++)
207            if (mag01[x] != other.mag01[x]) return false;
208        for(int x=0;x<mt.length;x++)
209            if (mt[x] != other.mt[x]) return false;
210        return true;
211        }
212
213    /** Reads the entire state of the MersenneTwister RNG from the stream */
214    public void readState(DataInputStream stream) throws IOException
215        {
216        int len = mt.length;
217        for(int x=0;x<len;x++) mt[x] = stream.readInt();
218       
219        len = mag01.length;
220        for(int x=0;x<len;x++) mag01[x] = stream.readInt();
221       
222        mti = stream.readInt();
223        __nextNextGaussian = stream.readDouble();
224        __haveNextNextGaussian = stream.readBoolean();
225        }
226       
227    /** Writes the entire state of the MersenneTwister RNG to the stream */
228    public void writeState(DataOutputStream stream) throws IOException
229        {
230        int len = mt.length;
231        for(int x=0;x<len;x++) stream.writeInt(mt[x]);
232       
233        len = mag01.length;
234        for(int x=0;x<len;x++) stream.writeInt(mag01[x]);
235       
236        stream.writeInt(mti);
237        stream.writeDouble(__nextNextGaussian);
238        stream.writeBoolean(__haveNextNextGaussian);
239        }
240
241
242    /**
243     * Constructor using the default seed.
244     */
245    public MersenneTwister()
246        {
247        this(System.currentTimeMillis());
248        }
249   
250    /**
251     * Constructor using a given seed.  Though you pass this seed in
252     * as a long, it's best to make sure it's actually an integer.
253     */
254    public MersenneTwister(final long seed)
255        {
256        super(seed);    /* just in case */
257        setSeed(seed);
258        }
259   
260    /**
261     * Constructor using an array of integers as seed.
262     * Your array must have a non-zero length.  Only the first 624 integers
263     * in the array are used; if the array is shorter than this then
264     * integers are repeatedly used in a wrap-around fashion.
265     */
266    public MersenneTwister(final int[] array)
267        {
268        super(System.currentTimeMillis());    /* pick something at random just in case */
269        setSeed(array);
270        }
271
272    /**
273     * Initalize the pseudo random number generator.  Don't
274     * pass in a long that's bigger than an int (Mersenne Twister
275     * only uses the first 32 bits for its seed).   
276     */
277
278    synchronized public void setSeed(final long seed)
279        {
280        // it's always good style to call super
281        super.setSeed(seed);
282
283        // Due to a bug in java.util.Random clear up to 1.2, we're
284        // doing our own Gaussian variable.
285        __haveNextNextGaussian = false;
286
287        mt = new int[N];
288       
289        mag01 = new int[2];
290        mag01[0] = 0x0;
291        mag01[1] = MATRIX_A;
292
293        mt[0]= (int)(seed & 0xffffffff);
294        for (mti=1; mti<N; mti++)
295            {
296            mt[mti] =
297                (1812433253 * (mt[mti-1] ^ (mt[mti-1] >>> 30)) + mti);
298            /* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
299            /* In the previous versions, MSBs of the seed affect   */
300            /* only MSBs of the array mt[].                        */
301            /* 2002/01/09 modified by Makoto Matsumoto             */
302            mt[mti] &= 0xffffffff;
303            /* for >32 bit machines */
304            }
305        }
306
307
308    /**
309     * Sets the seed of the MersenneTwister using an array of integers.
310     * Your array must have a non-zero length.  Only the first 624 integers
311     * in the array are used; if the array is shorter than this then
312     * integers are repeatedly used in a wrap-around fashion.
313     */
314
315    synchronized public void setSeed(final int[] array)
316        {
317        if (array.length == 0)
318            throw new IllegalArgumentException("Array length must be greater than zero");
319        int i, j, k;
320        setSeed(19650218);
321        i=1; j=0;
322        k = (N>array.length ? N : array.length);
323        for (; k!=0; k--)
324            {
325            mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >>> 30)) * 1664525)) + array[j] + j; /* non linear */
326            mt[i] &= 0xffffffff; /* for WORDSIZE > 32 machines */
327            i++;
328            j++;
329            if (i>=N) { mt[0] = mt[N-1]; i=1; }
330            if (j>=array.length) j=0;
331            }
332        for (k=N-1; k!=0; k--)
333            {
334            mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >>> 30)) * 1566083941)) - i; /* non linear */
335            mt[i] &= 0xffffffff; /* for WORDSIZE > 32 machines */
336            i++;
337            if (i>=N)
338                {
339                mt[0] = mt[N-1]; i=1;
340                }
341            }
342        mt[0] = 0x80000000; /* MSB is 1; assuring non-zero initial array */
343        }
344
345
346
347    /**
348     * Returns an integer with <i>bits</i> bits filled with a random number.
349     */
350    synchronized protected int next(final int bits)
351        {
352        int y;
353       
354        if (mti >= N)   // generate N words at one time
355            {
356            int kk;
357            final int[] mt = this.mt; // locals are slightly faster
358            final int[] mag01 = this.mag01; // locals are slightly faster
359           
360            for (kk = 0; kk < N - M; kk++)
361                {
362                y = (mt[kk] & UPPER_MASK) | (mt[kk+1] & LOWER_MASK);
363                mt[kk] = mt[kk+M] ^ (y >>> 1) ^ mag01[y & 0x1];
364                }
365            for (; kk < N-1; kk++)
366                {
367                y = (mt[kk] & UPPER_MASK) | (mt[kk+1] & LOWER_MASK);
368                mt[kk] = mt[kk+(M-N)] ^ (y >>> 1) ^ mag01[y & 0x1];
369                }
370            y = (mt[N-1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
371            mt[N-1] = mt[M-1] ^ (y >>> 1) ^ mag01[y & 0x1];
372
373            mti = 0;
374            }
375 
376        y = mt[mti++];
377        y ^= y >>> 11;                          // TEMPERING_SHIFT_U(y)
378        y ^= (y << 7) & TEMPERING_MASK_B;       // TEMPERING_SHIFT_S(y)
379        y ^= (y << 15) & TEMPERING_MASK_C;      // TEMPERING_SHIFT_T(y)
380        y ^= (y >>> 18);                        // TEMPERING_SHIFT_L(y)
381
382        return y >>> (32 - bits);    // hope that's right!
383        }
384   
385    /* If you've got a truly old version of Java, you can omit these
386       two next methods. */
387
388    private synchronized void writeObject(final ObjectOutputStream out)
389        throws IOException
390        {
391        // just so we're synchronized.
392        out.defaultWriteObject();
393        }
394
395    private synchronized void readObject (final ObjectInputStream in)
396        throws IOException, ClassNotFoundException
397        {
398        // just so we're synchronized.
399        in.defaultReadObject();
400        }   
401
402    /** This method is missing from jdk 1.0.x and below.  JDK 1.1
403        includes this for us, but what the heck.*/
404    public boolean nextBoolean() {return next(1) != 0;}
405
406    /** This generates a coin flip with a probability <tt>probability</tt>
407        of returning true, else returning false. <tt>probability</tt> must
408        be between 0.0 and 1.0, inclusive.  Not as precise a random real
409        event as nextBoolean(double), but twice as fast. To explicitly
410        use this, remember you may need to cast to float first. */
411
412    public boolean nextBoolean (final float probability)
413        {
414        if (probability < 0.0f || probability > 1.0f)
415            throw new IllegalArgumentException ("probability must be between 0.0 and 1.0 inclusive.");
416        if (probability==0.0f) return false;            // fix half-open issues
417        else if (probability==1.0f) return true;        // fix half-open issues
418        return nextFloat() < probability;
419        }
420
421    /** This generates a coin flip with a probability <tt>probability</tt>
422        of returning true, else returning false. <tt>probability</tt> must
423        be between 0.0 and 1.0, inclusive. */
424
425    public boolean nextBoolean (final double probability)
426        {
427        if (probability < 0.0 || probability > 1.0)
428            throw new IllegalArgumentException ("probability must be between 0.0 and 1.0 inclusive.");
429        if (probability==0.0) return false;             // fix half-open issues
430        else if (probability==1.0) return true; // fix half-open issues
431        return nextDouble() < probability;
432        }
433       
434    /** This method is missing from JDK 1.1 and below.  JDK 1.2
435        includes this for us, but what the heck. */
436
437    public int nextInt(final int n)
438        {
439        if (n<=0)
440            throw new IllegalArgumentException("n must be positive, got: " + n);
441       
442        if ((n & -n) == n)
443            return (int)((n * (long)next(31)) >> 31);
444       
445        int bits, val;
446        do
447            {
448            bits = next(31);
449            val = bits % n;
450            }
451        while(bits - val + (n-1) < 0);
452        return val;
453        }
454
455    /** This method is for completness' sake.
456        Returns a long drawn uniformly from 0 to n-1.  Suffice it to say,
457        n must be > 0, or an IllegalArgumentException is raised. */
458   
459    public long nextLong(final long n)
460        {
461        if (n<=0)
462            throw new IllegalArgumentException("n must be positive, got: " + n);
463       
464        long bits, val;
465        do
466            {
467            bits = (nextLong() >>> 1);
468            val = bits % n;
469            }
470        while(bits - val + (n-1) < 0);
471        return val;
472        }
473
474
475    /** A bug fix for versions of JDK 1.1 and below.  JDK 1.2 fixes
476        this for us, but what the heck. */
477    public double nextDouble()
478        {
479        return (((long)next(26) << 27) + next(27))
480            / (double)(1L << 53);
481        }
482
483    /** A bug fix for versions of JDK 1.1 and below.  JDK 1.2 fixes
484        this for us, but what the heck. */
485
486    public float nextFloat()
487        {
488        return next(24) / ((float)(1 << 24));
489        }
490
491    /** A bug fix for all versions of the JDK.  The JDK appears to
492        use all four bytes in an integer as independent byte values!
493        Totally wrong. I've submitted a bug report. */
494
495    public void nextBytes(final byte[] bytes)   
496        {
497        for (int x=0;x<bytes.length;x++) bytes[x] = (byte)next(8);
498        }
499
500    /** For completeness' sake, though it's not in java.util.Random.  */
501   
502    public char nextChar()
503        {
504        // chars are 16-bit UniCode values
505        return (char)(next(16));
506        }
507
508    /** For completeness' sake, though it's not in java.util.Random. */
509   
510    public short nextShort()
511        {
512        return (short)(next(16));
513        }
514
515    /** For completeness' sake, though it's not in java.util.Random.  */
516
517    public byte nextByte()
518        {
519        return (byte)(next(8));
520        }
521
522
523    /** A bug fix for all JDK code including 1.2.  nextGaussian can theoretically
524        ask for the log of 0 and divide it by 0! See Java bug
525        <a href="http://developer.java.sun.com/developer/bugParade/bugs/4254501.html">
526        http://developer.java.sun.com/developer/bugParade/bugs/4254501.html</a>
527    */
528
529    synchronized public double nextGaussian()
530        {
531        if (__haveNextNextGaussian)
532            {
533            __haveNextNextGaussian = false;
534            return __nextNextGaussian;
535            }
536        else
537            {
538            double v1, v2, s;
539            do
540                {
541                v1 = 2 * nextDouble() - 1; // between -1.0 and 1.0
542                v2 = 2 * nextDouble() - 1; // between -1.0 and 1.0
543                s = v1 * v1 + v2 * v2;
544                } while (s >= 1 || s==0 );
545            double multiplier = StrictMath.sqrt(-2 * StrictMath.log(s)/s);
546            __nextNextGaussian = v2 * multiplier;
547            __haveNextNextGaussian = true;
548            return v1 * multiplier;
549            }
550        }
551   
552    /**
553     * Tests the code.
554     */
555    public static void main(String args[])
556        {
557        int j;
558
559        MersenneTwister r;
560
561        // CORRECTNESS TEST
562        // COMPARE WITH http://www.math.keio.ac.jp/matumoto/CODES/MT2002/mt19937ar.out
563       
564        r = new MersenneTwister(new int[]{0x123, 0x234, 0x345, 0x456});
565        System.out.println("Output of MersenneTwister with new (2002/1/26) seeding mechanism");
566        for (j=0;j<1000;j++)
567            {
568            // first, convert the int from signed to "unsigned"
569            long l = (long)r.nextInt();
570            if (l < 0 ) l += 4294967296L;  // max int value
571            String s = String.valueOf(l);
572            while(s.length() < 10) s = " " + s;  // buffer
573            System.out.print(s + " ");
574            if (j%5==4) System.out.println();       
575            }
576
577        // SPEED TEST
578
579        final long SEED = 4357;
580
581        int xx; long ms;
582        System.out.println("\nTime to test grabbing 100000000 ints");
583         
584        r = new MersenneTwister(SEED);
585        ms = System.currentTimeMillis();
586        xx=0;
587        for (j = 0; j < 100000000; j++)
588            xx += r.nextInt();
589        System.out.println("Mersenne Twister: " + (System.currentTimeMillis()-ms) + "          Ignore this: " + xx);
590
591        System.out.println("To compare this with java.util.Random, run this same test on MersenneTwisterFast.");
592        System.out.println("The comparison with Random is removed from MersenneTwister because it is a proper");
593        System.out.println("subclass of Random and this unfairly makes some of Random's methods un-inlinable,");
594        System.out.println("so it would make Random look worse than it is.");
595
596        // TEST TO COMPARE TYPE CONVERSION BETWEEN
597        // MersenneTwisterFast.java AND MersenneTwister.java
598
599       
600        System.out.println("\nGrab the first 1000 booleans");
601        r = new MersenneTwister(SEED);
602        for (j = 0; j < 1000; j++)
603            {
604            System.out.print(r.nextBoolean() + " ");
605            if (j%8==7) System.out.println();
606            }
607        if (!(j%8==7)) System.out.println();
608         
609        System.out.println("\nGrab 1000 booleans of increasing probability using nextBoolean(double)");
610        r = new MersenneTwister(SEED);
611        for (j = 0; j < 1000; j++)
612            {
613            System.out.print(r.nextBoolean((double)(j/999.0)) + " ");
614            if (j%8==7) System.out.println();
615            }
616        if (!(j%8==7)) System.out.println();
617         
618        System.out.println("\nGrab 1000 booleans of increasing probability using nextBoolean(float)");
619        r = new MersenneTwister(SEED);
620        for (j = 0; j < 1000; j++)
621            {
622            System.out.print(r.nextBoolean((float)(j/999.0f)) + " ");
623            if (j%8==7) System.out.println();
624            }
625        if (!(j%8==7)) System.out.println();
626         
627        byte[] bytes = new byte[1000];
628        System.out.println("\nGrab the first 1000 bytes using nextBytes");
629        r = new MersenneTwister(SEED);
630        r.nextBytes(bytes);
631        for (j = 0; j < 1000; j++)
632            {
633            System.out.print(bytes[j] + " ");
634            if (j%16==15) System.out.println();
635            }
636        if (!(j%16==15)) System.out.println();
637       
638        byte b;
639        System.out.println("\nGrab the first 1000 bytes -- must be same as nextBytes");
640        r = new MersenneTwister(SEED);
641        for (j = 0; j < 1000; j++)
642            {
643            System.out.print((b = r.nextByte()) + " ");
644            if (b!=bytes[j]) System.out.print("BAD ");
645            if (j%16==15) System.out.println();
646            }
647        if (!(j%16==15)) System.out.println();
648
649        System.out.println("\nGrab the first 1000 shorts");
650        r = new MersenneTwister(SEED);
651        for (j = 0; j < 1000; j++)
652            {
653            System.out.print(r.nextShort() + " ");
654            if (j%8==7) System.out.println();
655            }
656        if (!(j%8==7)) System.out.println();
657
658        System.out.println("\nGrab the first 1000 ints");
659        r = new MersenneTwister(SEED);
660        for (j = 0; j < 1000; j++)
661            {
662            System.out.print(r.nextInt() + " ");
663            if (j%4==3) System.out.println();
664            }
665        if (!(j%4==3)) System.out.println();
666
667        System.out.println("\nGrab the first 1000 ints of different sizes");
668        r = new MersenneTwister(SEED);
669        int max = 1;
670        for (j = 0; j < 1000; j++)
671            {
672            System.out.print(r.nextInt(max) + " ");
673            max *= 2;
674            if (max <= 0) max = 1;
675            if (j%4==3) System.out.println();
676            }
677        if (!(j%4==3)) System.out.println();
678
679        System.out.println("\nGrab the first 1000 longs");
680        r = new MersenneTwister(SEED);
681        for (j = 0; j < 1000; j++)
682            {
683            System.out.print(r.nextLong() + " ");
684            if (j%3==2) System.out.println();
685            }
686        if (!(j%3==2)) System.out.println();
687
688        System.out.println("\nGrab the first 1000 longs of different sizes");
689        r = new MersenneTwister(SEED);
690        long max2 = 1;
691        for (j = 0; j < 1000; j++)
692            {
693            System.out.print(r.nextLong(max2) + " ");
694            max2 *= 2;
695            if (max2 <= 0) max2 = 1;
696            if (j%4==3) System.out.println();
697            }
698        if (!(j%4==3)) System.out.println();
699         
700        System.out.println("\nGrab the first 1000 floats");
701        r = new MersenneTwister(SEED);
702        for (j = 0; j < 1000; j++)
703            {
704            System.out.print(r.nextFloat() + " ");
705            if (j%4==3) System.out.println();
706            }
707        if (!(j%4==3)) System.out.println();
708
709        System.out.println("\nGrab the first 1000 doubles");
710        r = new MersenneTwister(SEED);
711        for (j = 0; j < 1000; j++)
712            {
713            System.out.print(r.nextDouble() + " ");
714            if (j%3==2) System.out.println();
715            }
716        if (!(j%3==2)) System.out.println();
717
718        System.out.println("\nGrab the first 1000 gaussian doubles");
719        r = new MersenneTwister(SEED);
720        for (j = 0; j < 1000; j++)
721            {
722            System.out.print(r.nextGaussian() + " ");
723            if (j%3==2) System.out.println();
724            }
725        if (!(j%3==2)) System.out.println();
726       
727        }
728   
729    }
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