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@mbostock
Forked from mbostock/.block
Last active Feb 9, 2016
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Sankey Interpolation
license: gpl-3.0
x y
0 1
1 5
2 3
3 8
4 5
<!DOCTYPE html>
<meta charset="utf-8">
<style>
body {
font: 10px sans-serif;
}
.axis path,
.axis line {
fill: none;
stroke: #000;
shape-rendering: crispEdges;
}
.line {
fill: none;
stroke: steelblue;
stroke-width: 1.5px;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var margin = {top: 20, right: 30, bottom: 30, left: 40},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom;
var x = d3.scale.linear()
.range([0, width]);
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");
var line = d3.svg.line()
.interpolate(interpolateSankey)
.x(function(d) { return x(d.x); })
.y(function(d) { return y(d.y); });
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) {
if (error) throw error;
data.forEach(function(d) {
d.x = +d.x;
d.y = +d.y;
});
x.domain(d3.extent(data, function(d) { return d.x; }));
y.domain(d3.extent(data, function(d) { return d.y; }));
svg.append("g")
.attr("class", "x axis")
.attr("transform", "translate(0," + height + ")")
.call(xAxis);
svg.append("g")
.attr("class", "y axis")
.call(yAxis);
svg.append("path")
.datum(data)
.attr("class", "line")
.attr("d", line);
});
function interpolateSankey(points) {
var x0 = points[0][0], y0 = points[0][1], x1, y1, x2,
path = [x0, ",", y0],
i = 0,
n = points.length;
while (++i < n) {
x1 = points[i][0], y1 = points[i][1], x2 = (x0 + x1) / 2;
path.push("C", x2, ",", y0, " ", x2, ",", y1, " ", x1, ",", y1);
x0 = x1, y0 = y1;
}
return path.join("");
}
</script>
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