Tributary inlet

_.md

[ Launch: Tributary inlet ] 6843559 by hyponymous

config.json

{"description":"Tributary inlet","endpoint":"","display":"svg","public":true,"require":[],"fileconfigs":{"inlet.js":{"default":true,"vim":false,"emacs":false,"fontSize":12},"style.css":{"default":true,"vim":false,"emacs":false,"fontSize":12},"_.md":{"default":true,"vim":false,"emacs":false,"fontSize":12},"config.json":{"default":true,"vim":false,"emacs":false,"fontSize":12}},"fullscreen":false,"play":false,"loop":false,"restart":false,"autoinit":true,"pause":true,"loop_type":"pingpong","bv":false,"nclones":15,"clone_opacity":0.4,"duration":3000,"ease":"linear","dt":0.01,"thumbnail":"http://i.imgur.com/yqTQXXQ.png"}

inlet.js

var svg = d3.select("svg");
var g = svg.append("g");
g.attr("transform", "translate(10, 10)");

var factDict = {};
function fact(N)
{
    if (N === 0)
    {
        return 1;
    }
    if (factDict[N])
    {
        return factDict[N];
    }
    return N * fact(N - 1);
}

var N = 30;
var p = 0.05;

function choose(N, k)
{
    return fact(N) / (fact(k) * fact(N - k));
}

var data = d3.range(N).map(function (i)
{
	return choose(N, i) * Math.pow(p, i) * Math.pow(1 - p, N - i);
});

var width = 480;
var height = 360;

var xScale = d3.scale.ordinal().rangeRoundBands([0, width], 0.1);
var yScale = d3.scale.linear().range([height, 0]);

xScale.domain(data.map(function (d, i) { return i; }));
yScale.domain([0, d3.max(data)]);

g.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function (d, i) { return xScale(i); })
.attr("width", xScale.rangeBand())
.attr("y", function (d) { return yScale(d); })
.attr("height", function (d) { return height - yScale(d); })
;

style.css

.bar
{
    fill: steelBlue;
}