dc
Version:
A multi-dimensional charting library built to work natively with crossfilter and rendered using d3.js
83 lines (72 loc) • 2.81 kB
HTML
<html lang="en">
<head>
<title>dc.js - Bar Chart with Extra Line Example</title>
<meta charset="UTF-8">
<link rel="stylesheet" type="text/css" href="../css/bootstrap.min.css">
<link rel="stylesheet" type="text/css" href="../css/dc.css"/>
</head>
<body>
<div class="container">
<script type="text/javascript" src="header.js"></script>
<div id="test"></div>
<p style="clear:left">Example of drawing an extra line on top of a bar chart using a renderlet. This is often
wanted in order to show e.g. a regression line.</p>
<p>It would be nice to have better support in
dc.js for such "derived" values, but this example is here to tide folks over until that happens.</p>
<script type="text/javascript" src="../js/d3.js"></script>
<script type="text/javascript" src="../js/crossfilter.js"></script>
<script type="text/javascript" src="../js/dc.js"></script>
<script type="text/javascript">
var chart = dc.barChart("#test");
d3.csv("morley.csv", function(error, experiments) {
experiments.forEach(function(x) {
x.Speed = +x.Speed;
});
var ndx = crossfilter(experiments),
runDimension = ndx.dimension(function(d) {return +d.Run;}),
speedSumGroup = runDimension.group().reduceSum(function(d) {return d.Speed * d.Run / 1000;});
chart
.width(768)
.height(480)
.x(d3.scale.linear().domain([6,20]))
.brushOn(false)
.yAxisLabel("This is the Y Axis!")
.dimension(runDimension)
.group(speedSumGroup)
.renderLabel(true)
.on('renderlet', function(chart) {
chart.selectAll('rect').on("click", function(d) {
console.log("click!", d);
});
var left_y = 10, right_y = 70; // use real statistics here!
var extra_data = [{x: chart.x().range()[0], y: chart.y()(left_y)}, {x: chart.x().range()[1], y: chart.y()(right_y)}];
var line = d3.svg.line()
.x(function(d) { return d.x; })
.y(function(d) { return d.y; })
.interpolate('linear');
var chartBody = chart.select('g.chart-body');
var path = chartBody.selectAll('path.extra').data([extra_data]);
path.enter().append('path').attr({
class: 'extra',
stroke: 'red',
id: 'extra-line'
});
path.attr('d', line);
// and perhaps you'd like to label it?
var text = chartBody.selectAll('text.extra-label').data([0]);
text.enter().append('text')
.attr('text-anchor', 'middle')
.append('textPath').attr({
class: 'extra-label',
'xlink:href': '#extra-line',
startOffset: '50%'
})
.text('this is a label for the line');
});
chart.render();
});
</script>
</div>
</body>
</html>