Random Histogram

Histogram for Reddit! http://www.reddit.com/r/javascript/comments/11qt9e/til_mathrandom_is_not_random_enough_for_a_raffle/

by intrinsica

CSS

body {
  font: 10px sans-serif;
}

.bar rect {
  fill: steelblue;
  shape-rendering: crispEdges;
}

.axis path, .axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

JavaScript

// Generate random numbers between 0 and 1
// 10 million of numbers. Wait a bunch of seconds please.
var values = []

var seed = 32453;
function c(a){
var b=this.b=Array(4);b[0]=4058668781;b[1]=b[2]=b[3]=a>>>0;for(b=0;20>b;b++)this.next();return this}
c.prototype.next=function(){var a=this.b,b=a[1];b=a[0]-(b<<27|b>>5)>>>0;var d=a[2];a[0]=(a[1]^(d<<17|d>>15))>>>0;a[1]=a[2]+a[3]>>>0;a[2]=a[3]+b>>>0;a[3]=b+a[0]>>>0;return a[3]};
c.prototype["float"]=function(){return this.next()/4294967296};
var xx = new c(seed);
//console.log(xx.float());

BINS = 300;
NUMBERS = 10000000;
GENERATOR = xx.float;

for (var i = 0; i < NUMBERS; i++) {
    values.push(xx.float());
}
        
// A formatter for counts.
var formatCount = d3.format(",.0f");

var margin = {top: 10, right: 30, bottom: 30, left: 30},
    width = 800 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

var x = d3.scale.linear()
    .domain([0,1])
    .range([0, width]);

// Generate a histogram using 15 uniformly-spaced bins.
var data = d3.layout.histogram()
    .bins(x.ticks(BINS))
    (values);

var y = d3.scale.linear()
    .domain([0, d3.max(data, function(d) { return d.y; })])
    .range([height, 0]);

var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");

var svg = d3.select("body").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

var bar = svg.selectAll(".bar")
    .data(data)
  .enter().append("g")
    .attr("class", "bar")
    .attr("transform", function(d) { return "translate(" + x(d.x) + "," + y(d.y) + ")"; });

bar.append("rect")
    .attr("x", 1)
    .attr("width", x(data[0].dx) - 1)
    .attr("height", function(d) { return height - y(d.y); });

svg.append("g")
    .attr("class", "x axis")
    .attr("transform", "translate(0," + height + ")")
    .call(xAxis);