Stacked-to-Grouped-to-Normalized Bars

A reworked example of stacked-to-grouped bars in which normalized stacked bars is added.

<!DOCTYPE html>
<meta charset="utf-8">
<style>

body {
        font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
        margin: auto;
        position: relative;
        width: 960px;
    }

text {
        font: 10px sans-serif;
    }

.axis path,
    .axis line {
        fill: none;
        stroke: #000;
        shape-rendering: crispEdges;
    }

form {
        position: absolute;
        right: 10px;
        top: 10px;
    }

</style>
<form>
    <label><input type="radio" name="mode" value="grouped"> Grouped</label>
    <label><input type="radio" name="mode" value="stacked" checked> Stacked</label>
    <label><input type="radio" name="mode" value="normalized"> Normalized</label>
</form>
<script src="https://d3js.org/d3.v3.min.js"></script>
<script>

// adding the value totals to each data object
    // Needed for calculating normalized values.
    layers.forEach(function(layer) {
        layer.forEach(function(d, i) {
            var last = layers[n - 1][i];
            d.total = last.y0 + last.y;
        })
    });

var margin = {top: 40, right: 10, bottom: 20, left: 10},
        width = 960 - margin.left - margin.right,
        height = 500 - margin.top - margin.bottom;

var x = d3.scale.ordinal()
        .domain(d3.range(m))
        .rangeRoundBands([0, width], .08);

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

var color = d3.scale.linear()
        .domain([0, n - 1])
        .range(["#aad", "#556"]);

var xAxis = d3.svg.axis()
        .scale(x)
        .tickSize(0)
        .tickPadding(6)
        .orient("bottom");

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 + ")");

var layer = svg.selectAll(".layer")
        .data(layers)
        .enter().append("g")
        .attr("class", "layer")
        .style("fill", function(d, i) { return color(i); });

var rect = layer.selectAll("rect")
        .data(function(d) { return d; })
        .enter().append("rect")
        .attr("x", function(d) { return x(d.x); })
        .attr("y", height)
        .attr("width", x.rangeBand())
        .attr("height", 0);

rect.transition()
        .delay(function(d, i) { return i * 10; })
        .attr("y", function(d) { return y(d.y0 + d.y); })
        .attr("height", function(d) { return y(d.y0) - y(d.y0 + d.y); });

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

d3.selectAll("input").on("change", change);

var timeout = setTimeout(function() {
        d3.select("input[value=\"grouped\"]").property("checked", true).each(change);
    }, 2000);

function transitionGrouped() {
        y.domain([0, yGroupMax]);

rect.transition()
            .duration(500)
            .delay(function(d, i) { return i * 10; })
            .attr("x", function(d, i, j) { return x(d.x) + x.rangeBand() / n * j; })
            .attr("width", x.rangeBand() / n)
            .transition()
            .attr("y", function(d) { return y(d.y); })
            .attr("height", function(d) { return height - y(d.y); });
    }

function transitionStacked() {
        y.domain([0, yStackMax]);

rect.transition()
            .duration(500)
            .delay(function(d, i) { return i * 10; })
            .attr("y", function(d) { return y(d.y0 + d.y); })
            .attr("height", function(d) { return y(d.y0) - y(d.y0 + d.y); })
            .transition()
            .attr("x", function(d) { return x(d.x); })
            .attr("width", x.rangeBand());
    }

function transitionNormalized() {
        y.domain([0, 100]);

rect.transition()
            .duration(500)
            .delay(function(d, i) { return i * 10; })
            .attr("y", function(d) { return y(100 * ((d.y0 + d.y)/ d.total)); })
            .attr("height", function(d) { return height - y(d.y/ d.total * 100); })
            .transition()
            .attr("x", function(d) { return x(d.x); })
            .attr("width", x.rangeBand());
    }

// Inspired by Lee Byron's test data generator.
    function bumpLayer(n, o) {

function bump(a) {
            var x = 1 / (.1 + Math.random()),
                y = 2 * Math.random() - .5,
                z = 10 / (.1 + Math.random());
            for (var i = 0; i < n; i++) {
                var w = (i / n - y) * z;
                a[i] += x * Math.exp(-w * w);
            }
        }

var a = [], i;
        for (i = 0; i < n; ++i) a[i] = o + o * Math.random();
        for (i = 0; i < 5; ++i) bump(a);
        return a.map(function(d, i) { return {x: i, y: Math.max(0, d)}; });
    }

</script>

Modified http://d3js.org/d3.v3.min.js to a secure url

https://d3js.org/d3.v3.min.js