d3 graph example

by Richard Hunter

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
<h2>My Graph</h2>

<svg id="canvas"></svg>

CSS

#canvas {
    border : solid 1px black;
}
rect {
    fill : green;
}
.axis text {
    font: 10px sans-serif;
}
.axis path, .axis line {
    fill: none;
    stroke: #000;
    shape-rendering: crispEdges;
}

JavaScript

var canvasWidth = 500,
    canvasHeight = 400;

//  create canvas
var canvas = d3.select('#canvas');
canvas.attr('width', canvasWidth);
canvas.attr('height', canvasHeight);

var margins = {
    left: 30,
    top: 20,
    right: 20,
    bottom: 30
};

var width = canvasWidth - (margins.left + margins.right);
var height = canvasHeight - (margins.top + margins.bottom);

var data = [{
    name: 'Dundee',
    points: 50
}, {
    name: 'Aberdeen',
    points: 60
}, {
    name: 'Celtic',
    points: 95
}];

//  configure y scale
var y = d3.scale.linear()
    .range([height, 0])
    .domain([0, d3.max(data, function (d) {
        return d.points;
    })]);

//  configure x scale
var x = d3.scale.ordinal()
    .rangeRoundBands([0, width])
    .domain(data.map(function (d) {
        return d.name;
    }));

//  place chart within group element
var chart = canvas.append('g')
    .attr('transform', 'translate(' + margins.left + ',' + margins.top + ')');

var barWidth = x.rangeBand();

//  create bar and bind data
var bar = chart.selectAll('g')
    .data(data)
    .enter()
    .append('g')
    .attr("transform", function (d) {
        return "translate(" + x(d.name) + ",0)";
    });

//  append rectangle
bar.append("rect")
    .attr("y", function (d) {
        return y(d.points);
    })
    .attr("height", function (d) {
        return height - y(d.points);
    })
    .attr("width", barWidth - 1);

//  create x axis
var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");

//  attach x axis
chart
  .append("g")
    .attr("class", "x axis")
    .attr("transform", "translate(0," + height + ")")
    .call(xAxis);

//  create y axis
var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left");

//  attach y axis and label
chart
  .append("g")
    .attr("class", "y axis")
    .call(yAxis)
 .append("text")
    .attr("transform", "rotate(-90)")
    .attr("y", 6)
    .attr("dy", ".71em")
    .style("text-anchor", "end")
    .text("Points");