c4se記:さっちゃんですよ☆

.。oO(さっちゃんですよヾ(〃l _ l)ノ゙☆)

.。oO(此のblogは、主に音樂考察Programmingに分類されますよ。ヾ(〃l _ l)ノ゙♬♪♡

音樂はSoundCloud等バラバラの場所に公開中です。申し訳ないがlinkをたどるなどして探してください。

考察は現在は主に此のblogで公表中です。

programmingは、ひろくみせるものはGitHubで、個人的なものはBitBucketで開発中です。

c4se

?????Ʊˡ??JS Native?˾??ä???

®?٤????ʤ??衣
LCG-random.js
?????????μ??ϡ?

x_n = (421 * x_{n-1} + 3) mod 1e+16

?????ɡ?

<html><head><title>c4sey Randoms</title></head><body><script type="application/javascript">
/* ========== cross env ========== */
if(!Array.prototype.clone)
Array.prototype.clone = function(){
  var a = new Array();
  for(var i=0; i<this.length; i++){
    if(this[i]._className != "Array")
      a[a.length] = this[i];
    else
      a[a.length] = this[i].clone();
  }
  return a;
};
if(!Array.prototype.forEach)
Array.prototype.forEach = function(f, o){
  if(o == null) o = undefined;
  for(var i=0; i<this.length; i++){
    if(!this[i]) continue;
    f.call(o, this[i], i, this);
  }
  return this;
};
if(!Array.prototype.map)
Array.prototype.map = function(f, o){
  if(o == null) o = undefined;
  var a = new Array();
  for(var i=0; i<this.length; i++){
    if(!this[i]) continue;
    a[a.length] = f.call(o, this[i], i, this);
  }
  return a;
};
if(!Array.prototype.reduce)
Array.prototype.reduce = function(f, v){
  var i = 0;
  if(v == null){v = this[0]; i = 1;}
  for(i; i<this.length; i++){
    if(!this[i]) continue;
    v = f.call(null, v, this[i], i, this);
  }
  return v;
};
if(!Array.prototype.reduceRight)
Array.prototype.reduceRight = function(f, v){
  var i = this.length - 1;
  if(v == null){v = this[i]; i--;}
  for(i; i>=0; i--){
    if(this[i] === undefined) continue;
    v = f.call(null, v, this[i], i, this);
  }
  return v;
};


/* ========== Statistics ========== */
stat = (function(){
  var sum = function(a){
    return a.reduce(function(v, elm){return v + elm;});
  };
  var average = function(data){return sum(data) / data.length;};
  var variance = function(data){
    var av = average(data);
    return sum(data.map(function(elm){return Math.pow(elm - av, 2);})) / data.length;
  };
  var sd = function(data){return Math.sqrt(variance(data));};
  
  return {
    average: average,
    variance: variance,
    sd: sd
  };
})();


/* ========== def Random functions ========== */
random = {};
random.jsn = function(n){
  var r = new Array(n);
  for(var i=0; i<n; i++)
    r[i] = Math.random();
  return r;
};
random.lcg = function(n, s, a){
  var tf = true;
  if(!n){n = 100; tf = false;}
  if(!s) s = (new Date()).getTime();
  if(!a) a = new Array(421, 3, 1e+16);
  var suc = function(x){return (a[0] * x + a[1]) % a[2];};
  var r = new Array(n);
  for(var i=0; i<n; i++){
    s = suc(s);
    r[i] = s / 1e+16;
  }
  return (tf) ? r : r[99];
};


/* ========== Test code ========== */
(function(){

var rTest = function(_round){
  var doTest = function(f){
    var time1 = (new Date()).getTime();
    var arr = f.call(null, _round);
    var time2 = (new Date()).getTime();
    arr = arr.map(function(elm){return Math.floor(elm * 10);});
    var am = [0,0,0,0,0,0,0,0,0,0];
    arr.forEach(function(elm){++am[elm];});
    return {
      t: time2 - time1,
      data: am,
      v: stat.variance(am),
      sd: stat.sd(am)
    };
  };
  var printTest = function(f){
    var o = doTest(f);
    document.write("<td>" + o.v + "</td>");
    document.write("<td>" + o.sd + "</td>");
    document.write("<td>" + o.t + "</td>");
    document.write("<td>" + o.data.join(", ") + "</td>");
  };
  document.open();
  document.write("round = " + _round + "<br/>");
  document.write("<table border='1'><tr><th></th><th>variance</th><th>standerd deviation</th><th>time</th><th>DATA</th></tr>");
  document.write("<tr><th>JS Native</th>");
  printTest(random.jsn);
  document.write("</tr><tr><th>LCG</th>");
  printTest(random.lcg);
  document.write("</tr></table>");
  document.close();
};
//rTest(10000);
rTest(50000);
rTest(100000);
rTest(1000000);

})();
</script></body></html>