Random Histogram
Histogram for Reddit!
http://www.reddit.com/r/javascript/comments/11qt9e/til_mathrandom_is_not_random_enough_for_a_raffle/
HTML
<body>
<script src="http://d3js.org/d3.v2.min.js?2.10.0"></script>
</body>
CSS
body {
font: 10px sans-serif;
}
.bar rect {
fill: steelblue;
shape-rendering: crispEdges;
}
.bar text {
fill: #fff;
}
.axis path, .axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
JavaScript
// Generate 40 random numbers between 100 and 2400
var values = []
var seed = 1;
function random() {
var x = Math.sin(seed++) * 10000;
return x - Math.floor(x);
}
BINS = 100;
NUMBERS = 10000000;
GENERATOR = random;
for (var i = 0; i < NUMBERS; i++) {
values.push(GENERATOR());
}
// 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); });
bar.append("text")
.attr("dy", ".75em")
.attr("y", 6)
.attr("x", x(data[0].dx) / 2)
.attr("text-anchor", "middle")
.text(function(d) { return formatCount(d.y); });
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);