Up until now we've just looked at bar charts. A handy chart, no doubt, but D3 offers a variety of charts you can work with. In this lesson we'll convert the bar chart into a basic scatter (or bubble) chart.
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
<script src="../bower_components/underscore/underscore-min.js"></script>
<script src="../ventor/d3.min.js"></script>
<style type="text/css"> body
{
padding-top: 50px;
padding-left: 100px; } #chartArea {
width: 400px;
height: 300px;
background-color: #CCC;
} .bar
{
display: inline-block;
width: 20px;
height: 75px; /* Gets overriden by D3-assigned height below */
margin-right: 2px;
/* fill: teal; *//* SVG doesn't have background prop, use fill instead*/
z-index:99;
} .bubble {
display: inline-block;
fill: purple;
fill-opacity: 0.5;
stroke: black;
stroke-weight: 1px;
} </style>
</head>
<body>
<section id="chartArea"></section>
<script>
var dataset = _.map(_.range(30), function(num) {
return {
x: Math.random() * 100,
y: Math.random() * 100,
r: Math.random() * 30
} }), //reandom generate 15 data from 1 to 50
margin = {top: 0, bottom: 0, left: 0, right: 0},
w = 400 - margin.left - margin.right,
h = 300 -margin.top - margin.bottom; var svg = d3.select('#chartArea').append('svg')
.attr('width', w + margin.left + margin.right)
.attr('height', h + margin.top + margin.bottom)
.append('g') //The last step is to add a G element which is a graphics container in SBG.
.attr('transform', 'translate(' + margin.left + ', ' + margin.top + ')'); //Then offset that graphic element by our left and top margins. var yScale = d3.scale.linear()
.domain([0, d3.max(dataset, function(d) {
return d.y; //tell the max function just need to care about y prop
})])
.range([h, 0]); var xScale = d3.scale.linear()
.domain([0, 100])
.range([0, w]); svg.selectAll('circle')
.data(dataset)
.enter()
.append('circle')// svg doesn't have div, use rect instead
.attr('class', "bubble")
.attr('cx', function(each_data, index){
return xScale(each_data.x);
})
.attr('cy', function(each_data){
return yScale(each_data.y);
})
.attr('r', function(each_data, i){
return each_data.r;
});
</script>
</body>
</html>