<!DOCTYPE html>
<html>
<head>
<title>Force-Directed Layout</title>
<script type="text/javascript" src="../../d3.js"></script>
<script type="text/javascript" src="../../d3.geom.js"></script>
<script type="text/javascript" src="../../d3.layout.js"></script>
<style type="text/css">
circle {
stroke-width: 1.5px;
}
line {
stroke: #999;
}
</style>
</head>
<body>
<script type="text/javascript">
var w = 960,
h = 500,
r = 6,
fill = d3.scale.category20();
var force = d3.layout.force()
.gravity(.01)
.charge(-120)
.linkDistance(30)
.size([w, h]);
var svg = d3.select("body").append("svg:svg")
.attr("width", w)
.attr("height", h);
d3.json("miserables.json", function(json) {
var link = svg.selectAll("line")
.data(json.links)
.enter().append("svg:line");
var node = svg.selectAll("circle")
.data(json.nodes)
.enter().append("svg:circle")
.attr("r", r - .75)
.style("fill", function(d) { return fill(d.group); })
.style("stroke", function(d) { return d3.rgb(fill(d.group)).darker(); })
.call(force.drag);
force
.nodes(json.nodes)
.links(json.links)
.on("tick", tick)
.start();
function tick() {
node.attr("cx", function(d) { return d.x = Math.max(r, Math.min(w - r, d.x)); })
.attr("cy", function(d) { return d.y = Math.max(r, Math.min(h - r, d.y)); });
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
}
});
</script>
</body>
</html>