D3 | Waterfall Chart

by Anonymous

HTML

<!DOCTYPE html>
<svg class="chart"></svg>
<script src="http://d3js.org/d3.v3.min.js"></script>

CSS

.bar.total-positive rect {
    fill: #1ABC9C;
}
.bar.cumulative rect {
    fill: #9B59B6;
}
.bar.total-negative rect {
    fill: #E74C3C;
}
.bar.positive rect {
    fill: #1ABC9C;
}
.bar.negative rect {
    fill: #E74C3C;
}
.bar line.connector {
    stroke: grey;
    stroke-dasharray: 3;
}
.bar text {
    fill: white;
    font: 12px sans-serif;
    text-anchor: middle;
}
.axis text {
    font: 10px sans-serif;
}
.axis path, .axis line {
    fill: none;
    stroke: #000;
    shape-rendering: crispEdges;
}

JavaScript

var margin = {
    top: 20,
    right: 30,
    bottom: 30,
    left: 40
},
width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom,
    padding = 0.3;

var x = d3.scale.ordinal()
    .rangeRoundBands([0, width], padding);

var y = d3.scale.linear()
    .range([height, 0]);

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

var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left")
    .tickFormat(function (d) {
    return dollarFormatter(d);
});

var chart = d3.select(".chart")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
    .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

//TODO: don't use name as unique identifier
var data = [{
    name: 'AOP',
    value: 320000
}, {
    name: 'EP',
    value: -20000,
    area: 'Ekjslfdjls Psdfjskf'
}, {
    name: 'Cumulative 1',
    isCumulative: true
}, {
    name: 'AP 1',
    value: -70000,
    area: 'AP'
}, {
    name: 'AP 2',
    value: 30000,
    area: 'AP'
}, {
    name: 'Cumulative 2',
    isCumulative: true,
    area: 'AP'
}, {
    name: 'AP 3',
    value: -25000,
    area: 'AP'
}, {
    name: 'AP 4',
    value: -80000,
    area: 'AP'
}, {
    name: 'MS',
    value: 31000,
    area: 'MS'
}];


// Transform data (i.e., finding cumulative values and total) for easier charting
var cumulative = 0;
var currentArea;
var currentAreaStart = 0;
var currentAreaMax = 0;
var currentAreaLength = 1;
for (var i = 0; i < data.length; i++) {
    if (data[i].isCumulative) {
        data[i].start = 0;
        data[i].class = 'cumulative';
    } else {
        data[i].start = cumulative;
        data[i].class = (data[i].value >= 0) ? 'positive' : 'negative';
        cumulative += data[i].value;
    }

    data[i].end = cumulative;

    if (data[i].area) {
        if (data[i].area == undefined || currentArea != data[i].area) {
            // currentArea is now previous area
           ...