This is a simple graph demonstrating the display of multiple lines. This was written using d3.js v4 and is a follow on to the simple graph example here.
This graph is part of the code samples for the update to the book D3 Tips and Tricks to version 4 of d3.js.
<!DOCTYPE html>
<meta charset="utf-8">
<style> /* set the CSS */
.line {
fill: none;
stroke: steelblue;
stroke-width: 2px;
}
</style>
<body>
<!-- load the d3.js library -->
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
// set the dimensions and margins of the graph
var margin = {top: 20, right: 20, bottom: 30, left: 50},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
// parse the date / time
var parseTime = d3.timeParse("%d-%b-%y");
// set the ranges
var x = d3.scaleTime().range([0, width]);
var y = d3.scaleLinear().range([height, 0]);
// define the 1st line
var valueline = d3.line()
.x(function(d) { return x(d.date); })
.y(function(d) { return y(d.close); });
// define the 2nd line
var valueline2 = d3.line()
.x(function(d) { return x(d.date); })
.y(function(d) { return y(d.open); });
// append the svg obgect to the body of the page
// appends a 'group' element to 'svg'
// moves the 'group' element to the top left margin
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 + ")");
// Get the data
d3.csv("data2.csv", function(error, data) {
if (error) throw error;
// format the data
data.forEach(function(d) {
d.date = parseTime(d.date);
d.close = +d.close;
d.open = +d.open;
});
// Scale the range of the data
x.domain(d3.extent(data, function(d) { return d.date; }));
y.domain([0, d3.max(data, function(d) {
return Math.max(d.close, d.open); })]);
// Add the valueline path.
svg.append("path")
.data([data])
.attr("class", "line")
.attr("d", valueline);
// Add the valueline2 path.
svg.append("path")
.data([data])
.attr("class", "line")
.style("stroke", "red")
.attr("d", valueline2);
// Add the X Axis
svg.append("g")
.attr("transform", "translate(0," + height + ")")
.call(d3.axisBottom(x));
// Add the Y Axis
svg.append("g")
.call(d3.axisLeft(y));
});
</script>
</body>
date,close,open
1-May-12,68.13,34.12
30-Apr-12,63.98,45.56
27-Apr-12,67.00,67.89
26-Apr-12,89.70,78.54
25-Apr-12,99.00,89.23
24-Apr-12,130.28,99.23
23-Apr-12,166.70,101.34
20-Apr-12,234.98,122.34
19-Apr-12,345.44,134.56
18-Apr-12,443.34,160.45
17-Apr-12,543.70,180.34
16-Apr-12,580.13,210.23
13-Apr-12,605.23,223.45
12-Apr-12,622.77,201.56
11-Apr-12,626.20,212.67
10-Apr-12,628.44,310.45
9-Apr-12,636.23,350.45
5-Apr-12,633.68,410.23
4-Apr-12,624.31,430.56
3-Apr-12,629.32,460.34
2-Apr-12,618.63,510.34
30-Mar-12,599.55,534.23
29-Mar-12,609.86,578.23
28-Mar-12,617.62,590.12
27-Mar-12,614.48,560.34
26-Mar-12,606.98,580.12