/* This file is automatically rebuilt by the Cesium build process. */
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/*
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https://github.com/banksean wrapped Makoto Matsumoto and Takuji Nishimura's code in a namespace
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so it's better encapsulated. Now you can have multiple random number generators
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and they won't stomp all over eachother's state.
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If you want to use this as a substitute for Math.random(), use the random()
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method like so:
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var m = new MersenneTwister();
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var randomNumber = m.random();
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You can also call the other genrand_{foo}() methods on the instance.
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If you want to use a specific seed in order to get a repeatable random
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sequence, pass an integer into the constructor:
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var m = new MersenneTwister(123);
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and that will always produce the same random sequence.
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Sean McCullough (banksean@gmail.com)
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*/
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/*
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A C-program for MT19937, with initialization improved 2002/1/26.
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Coded by Takuji Nishimura and Makoto Matsumoto.
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Before using, initialize the state by using init_seed(seed)
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or init_by_array(init_key, key_length).
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Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
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All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions
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are met:
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1. Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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3. The names of its contributors may not be used to endorse or promote
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products derived from this software without specific prior written
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permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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Any feedback is very welcome.
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http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html
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email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
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*/
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var MersenneTwister = function(seed) {
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if (seed == undefined) {
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seed = new Date().getTime();
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}
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/* Period parameters */
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this.N = 624;
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this.M = 397;
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this.MATRIX_A = 0x9908b0df; /* constant vector a */
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this.UPPER_MASK = 0x80000000; /* most significant w-r bits */
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this.LOWER_MASK = 0x7fffffff; /* least significant r bits */
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this.mt = new Array(this.N); /* the array for the state vector */
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this.mti=this.N+1; /* mti==N+1 means mt[N] is not initialized */
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if (seed.constructor == Array) {
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this.init_by_array(seed, seed.length);
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}
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else {
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this.init_seed(seed);
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}
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};
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/* initializes mt[N] with a seed */
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/* origin name init_genrand */
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MersenneTwister.prototype.init_seed = function(s) {
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this.mt[0] = s >>> 0;
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for (this.mti=1; this.mti<this.N; this.mti++) {
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var s = this.mt[this.mti-1] ^ (this.mt[this.mti-1] >>> 30);
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this.mt[this.mti] = (((((s & 0xffff0000) >>> 16) * 1812433253) << 16) + (s & 0x0000ffff) * 1812433253)
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+ this.mti;
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/* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
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/* In the previous versions, MSBs of the seed affect */
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/* only MSBs of the array mt[]. */
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/* 2002/01/09 modified by Makoto Matsumoto */
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this.mt[this.mti] >>>= 0;
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/* for >32 bit machines */
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}
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};
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/* initialize by an array with array-length */
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/* init_key is the array for initializing keys */
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/* key_length is its length */
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/* slight change for C++, 2004/2/26 */
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MersenneTwister.prototype.init_by_array = function(init_key, key_length) {
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var i, j, k;
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this.init_seed(19650218);
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i=1; j=0;
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k = (this.N>key_length ? this.N : key_length);
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for (; k; k--) {
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var s = this.mt[i-1] ^ (this.mt[i-1] >>> 30);
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this.mt[i] = (this.mt[i] ^ (((((s & 0xffff0000) >>> 16) * 1664525) << 16) + ((s & 0x0000ffff) * 1664525)))
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+ init_key[j] + j; /* non linear */
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this.mt[i] >>>= 0; /* for WORDSIZE > 32 machines */
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i++; j++;
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if (i>=this.N) { this.mt[0] = this.mt[this.N-1]; i=1; }
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if (j>=key_length) j=0;
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}
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for (k=this.N-1; k; k--) {
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var s = this.mt[i-1] ^ (this.mt[i-1] >>> 30);
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this.mt[i] = (this.mt[i] ^ (((((s & 0xffff0000) >>> 16) * 1566083941) << 16) + (s & 0x0000ffff) * 1566083941))
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- i; /* non linear */
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this.mt[i] >>>= 0; /* for WORDSIZE > 32 machines */
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i++;
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if (i>=this.N) { this.mt[0] = this.mt[this.N-1]; i=1; }
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}
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this.mt[0] = 0x80000000; /* MSB is 1; assuring non-zero initial array */
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};
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/* generates a random number on [0,0xffffffff]-interval */
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/* origin name genrand_int32 */
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MersenneTwister.prototype.random_int = function() {
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var y;
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var mag01 = new Array(0x0, this.MATRIX_A);
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/* mag01[x] = x * MATRIX_A for x=0,1 */
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if (this.mti >= this.N) { /* generate N words at one time */
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var kk;
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if (this.mti == this.N+1) /* if init_seed() has not been called, */
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this.init_seed(5489); /* a default initial seed is used */
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for (kk=0;kk<this.N-this.M;kk++) {
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y = (this.mt[kk]&this.UPPER_MASK)|(this.mt[kk+1]&this.LOWER_MASK);
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this.mt[kk] = this.mt[kk+this.M] ^ (y >>> 1) ^ mag01[y & 0x1];
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}
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for (;kk<this.N-1;kk++) {
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y = (this.mt[kk]&this.UPPER_MASK)|(this.mt[kk+1]&this.LOWER_MASK);
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this.mt[kk] = this.mt[kk+(this.M-this.N)] ^ (y >>> 1) ^ mag01[y & 0x1];
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}
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y = (this.mt[this.N-1]&this.UPPER_MASK)|(this.mt[0]&this.LOWER_MASK);
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this.mt[this.N-1] = this.mt[this.M-1] ^ (y >>> 1) ^ mag01[y & 0x1];
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this.mti = 0;
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}
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y = this.mt[this.mti++];
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/* Tempering */
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y ^= (y >>> 11);
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y ^= (y << 7) & 0x9d2c5680;
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y ^= (y << 15) & 0xefc60000;
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y ^= (y >>> 18);
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return y >>> 0;
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};
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/* generates a random number on [0,0x7fffffff]-interval */
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/* origin name genrand_int31 */
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MersenneTwister.prototype.random_int31 = function() {
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return (this.random_int()>>>1);
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};
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/* generates a random number on [0,1]-real-interval */
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/* origin name genrand_real1 */
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MersenneTwister.prototype.random_incl = function() {
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return this.random_int()*(1.0/4294967295.0);
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/* divided by 2^32-1 */
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};
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/* generates a random number on [0,1)-real-interval */
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MersenneTwister.prototype.random = function() {
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return this.random_int()*(1.0/4294967296.0);
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/* divided by 2^32 */
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};
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/* generates a random number on (0,1)-real-interval */
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/* origin name genrand_real3 */
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MersenneTwister.prototype.random_excl = function() {
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return (this.random_int() + 0.5)*(1.0/4294967296.0);
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/* divided by 2^32 */
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};
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/* generates a random number on [0,1) with 53-bit resolution*/
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/* origin name genrand_res53 */
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MersenneTwister.prototype.random_long = function() {
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var a=this.random_int()>>>5, b=this.random_int()>>>6;
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return (a*67108864.0+b)*(1.0/9007199254740992.0);
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};
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/* These real versions are due to Isaku Wada, 2002/01/09 added */
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var mersenneTwister = MersenneTwister;
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export { mersenneTwister as default };
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