这个堆叠到分组的条形转换示例非常漂亮。但是，它是由随机数生成器运行的，对于我的一生，我无法弄清楚如何用我自己的数据集替换它。
http://bl.ocks.org/mbostock/3943967
如何让这个堆叠到分组的条形转换来导入和使用 .csv 文件而不是随机数据生成器？
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
font: 14px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.x.axis path {
display: none;
}
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>
</form>
<script src="http://d3js.org/d3.v3.min.js"></script>
<script>
var margin = {top: 20, right: 20, bottom: 30, left: 40},
width = 1000 - margin.left - margin.right,
height = 400 - margin.top - margin.bottom;
var stack = d3.layout.stack(),
layers = stack(d3.range(n).map(function() { return bumpLayer(m, .1); })),
yGroupMax = d3.max(layers, function(layer) { return d3.max(layer, function(d) { return d.y; }); }),
yStackMax = d3.max(layers, function(layer) { return d3.max(layer, function(d) { return d.y0 + d.y; }); });
var x = d3.scale.ordinal()
.rangeRoundBands([0, width], .1);
var y = d3.scale.linear()
.rangeRound([height, 0]);
var color = d3.scale.ordinal()
.range(["#aa0000", "#ffff66", "#99ff99", "#00aa00"]);
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 + ")");
d3.csv("data.csv", function(error, data) {
color.domain(d3.keys(data[0]).filter(function(key) { return key !== "Year"; }));
data.forEach(function(d) {
var y0 = 0;
d.power = color.domain().map(function(name) { return {name: name, y0: y0, y1: y0 += +d[name]}; });
d.total = d.power[d.power.length - 1].y1;
});
data.sort(function(b, a) { return b.total - a.total; });
x.domain(data.map(function(d) { return d.Year; }));
y.domain([0, d3.max(data, function(d) { return d.total; })]);
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.call(yAxis)
.append("text")
.attr("y", -8)
.attr("x", 40)
.attr("dy", "0em")
.style("text-anchor", "end")
.text("Power (Mw)");
var year = svg.selectAll(".year")
.data(data)
.enter().append("g")
.attr("class", "g")
.attr("transform", function(d) { return "translate(" + x(d.Year) + ",0)"; });
year.selectAll("rect")
.data(function(d) { return d.power; })
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.attr("y", function(d) { return y(d.y1); })
.attr("height", function(d) { return y(d.y0) - y(d.y1); })
.style("fill", function(d) { return color(d.name); });
var legend = svg.selectAll(".legend")
.data(color.domain().slice().reverse())
.enter().append("g")
.attr("class", "legend")
.attr("transform", function(d, i) { return "translate(0," + i * 20 + ")"; });
legend.append("rect")
.attr("x", width - 800)
.attr("width", 18)
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.style("fill", color);
legend.append("text")
.attr("x", width - 770)
.attr("y", 9)
.attr("dy", ".35em")
.style("text-anchor", "begin")
.text(function(d) { return d; });
});
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 change() {
clearTimeout(timeout);
if (this.value === "grouped") transitionGrouped();
else transitionStacked();
}
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());
}
</script>