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    <div id="timeline"></div>
	<img class="original-map" src=""/>
    function getMetrics() {
        var metrics = ["2000bc", "1950bc", "1900bc", "1850bc", "1800bc", "1750bc", "1700bc", "1650bc", "1600bc", "1550bc", "1500bc", "1450bc", "1400bc", "1350bc", "1300bc", "1250bc", "1200bc", "1150bc", "1100bc", "1050bc", "1000bc", "950bc", "900bc", "850bc", "800bc", "750bc", "700bc", "650bc", "600bc", "550bc", "500bc", "450bc", "400bc", "350bc", "300bc", "250bc", "200bc", "150bc", "100bc", "50bc", "0ad", "50ad", "100ad", "150ad", "200ad", "250ad", "300ad", "350ad", "400ad", "450ad", "500ad", "550ad", "600ad", "650ad", "700ad", "750ad", "800ad", "850ad", "900ad", "950ad", "1000ad", "1050ad", "1100ad", "1150ad", "1200ad", "1250ad", "1300ad", "1350ad", "1400ad", "1450ad", "1500ad", "1550ad", "1600ad", "1650ad", "1700ad", "1750ad", "1800ad", "1850ad", "1900ad", "~1950ad", "~2000ad"];
        return metrics;


                body {
	overflow: visible;

.axisYears path {
	fill: none;

.tick line {
	stroke: black;

$timeline-width: 800px;
#timeline {
	float: left;
	width: $timeline-width;
	padding-top: 30px;
	/* 	border: 1px solid green; */

.original-map {
	position: absolute;
	top: 0;
	left: $timeline-width;
	height: 2830px;
	float: left;
	/* 	border: 1px solid red; */


function (err, jsonResponse) {

    // NOTE: d is usually "current datum", per d3 convention.
    // e is usually something like "current array element".
    // i is usually "index of current datum or array element"

    //Grab our data
    var civData = jsonResponse,
        metrics = getMetrics();

    // Set some dimensions for our chart
    var width = 500,
        height = width * 5.3,
        padding = width/5;

    // Create the svg.
    // We make it a little bigger than the chart will be to account for labels overflowing (for now)
    var svg ="#timeline").append("svg")
        "width": width + 2 * padding,
            "height": height + 2 * padding

    // Create a scale for the x axis of our chart.
    // It scales from the layout scale (0,1) to the chart scale (0,width)
    // It also reverses it. I'm a little unclear on why.
    var xScale = d3.scale.linear()
        .domain([0, 1])
        .range([width, 0]);

    // Create a scale for the y axis of our chart, as above.
    var timeScale = d3.scale.linear()
        .domain([0, metrics.length - 1])
        .range([0, height]);

    // The stack function takes an array (layers) of arrays of objects (datapoints in each layer)
    // This bit constructs that array of arrays.

    civData.forEach(function (v, i, a) {
        v.layer = (metric, i) {
            return {
                x: i,
                y: v.metrics[metric]

    // Prep the stack layout function.
    // "expand" tells it to fill out the (0,1) space
    // "reverse" tells it to stack the layers in reverse order. I'm a little unclear on why.
    var stack = d3.layout.stack()
        .values(function (d) {
        return d.layer;

    // Use the stack function we configured earlier to lay out the chart
    layers = stack(civData);

    // The area function constructs a polygon from two lines, more or less.
    var area = d3.svg.area()
    // .y tells it to use the same y value for both lines, and to get it this way
    .y(function (d) {
        return timeScale(d.x) + padding;
    // .x0 tells it to get the x value for the left line this way
    .x0(function (d) {
        return xScale(null) + padding;
    // .x1 tells it to get the x value for the right line this way
    .x1(function (d) {
        return xScale(d.y0 + d.y) + padding;

    // NOTE: Area and stack sort of think of x and y differently.
    // Area means it literally: x and y on your svg/canvas.
    // Stack is more like y=direction things are stacked and x=direction things flow

    //Draw layers
        .attr("d", function (d) {
        return area(d.layer);
        "fill": function (d) {
            return d.color;
            "stroke": function (d) {
            return d3.hsl(d.color).darker(0.25);
            "stroke-width": width / 200

    //Draw text
        .each(function (d) {
        // Figure out what the layer's highest value is
        var max = d3.max(d.layer, function (e) {
            return e.y;
        // Figure out at what index that occurs
        var index = (e) {
            return e.y;
        // Place the text halfway between the left and right edges of the layer at that index
        var x = xScale(d.layer[index].y / 2 + d.layer[index].y0) + padding;
        // Place the text at that index, vertically
        var y = timeScale(d.layer[index].x) + padding;{
            "x": x,
                "y": y,
                "text-anchor": "middle",
            "class": "civName"
        .text(function (d) {

    //Create scale our of metrics
    var yearScale = d3.scale.ordinal().domain(metrics).rangePoints([0, height]);

    //Create left axis
    var leftAxis = d3.svg.axis().orient("left").scale(yearScale);
        .attr("transform", "translate(" + padding + "," + padding + ")")
        .attr("class", "axisYears")

    //Create right axis
    var rightAxis = d3.svg.axis().orient("right").scale(yearScale);
        .attr("transform", "translate(" + (padding + width) + "," + padding + ")")
        .attr("class", "axisYears")
    //Set civilization name font size relative to chart width
        .style("font-size", function () {
            return width/30;
    // Set axis font size relative to chart width
        .style("font-size", function () {
            return width/20;