The scatterplot matrix visualizations pairwise correlations for multi-dimensional data; each cell in the matrix is a scatterplot. This example uses Anderson’s data of iris flowers on the Gaspé Peninsula. Scatterplot matrix design invented by J. A. Hartigan; see also R and GGobi. Data on Iris flowers collected by Edgar Anderson and published by Ronald Fisher.
<!DOCTYPE html>
<meta charset="utf-8">
<style>
svg {
font: 10px sans-serif;
padding: 10px;
}
.axis,
.frame {
shape-rendering: crispEdges;
}
.axis line {
stroke: #ddd;
}
.axis path {
display: none;
}
.frame {
fill: none;
stroke: #aaa;
}
circle {
fill-opacity: .7;
}
circle.hidden {
fill: #ccc !important;
}
.extent {
fill: #000;
fill-opacity: .125;
stroke: #fff;
}
</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var width = 960,
size = 150,
padding = 19.5;
var x = d3.scale.linear()
.range([padding / 2, size - padding / 2]);
var y = d3.scale.linear()
.range([size - padding / 2, padding / 2]);
var xAxis = d3.svg.axis()
.scale(x)
.orient("bottom")
.ticks(5);
var yAxis = d3.svg.axis()
.scale(y)
.orient("left")
.ticks(5);
var color = d3.scale.category10();
d3.csv("flowers1.csv", function(error, data) {
var domainByTrait = {},
traits = d3.keys(data[0]).filter(function(d) { return d !== "species"; }),
n = traits.length;
traits.forEach(function(trait) {
domainByTrait[trait] = d3.extent(data, function(d) { return +d[trait]; });
});
xAxis.tickSize(size * n);
yAxis.tickSize(-size * n);
var brush = d3.svg.brush()
.x(x)
.y(y)
.on("brushstart", brushstart)
.on("brush", brushmove)
.on("brushend", brushend);
var svg = d3.select("body").append("svg")
.attr("width", size * n + padding)
.attr("height", size * n + padding)
.append("g")
.attr("transform", "translate(" + padding + "," + padding / 2 + ")");
svg.selectAll(".x.axis")
.data(traits)
.enter().append("g")
.attr("class", "x axis")
.attr("transform", function(d, i) { return "translate(" + (n - i - 1) * size + ",0)"; })
.each(function(d) { x.domain(domainByTrait[d]); d3.select(this).call(xAxis); });
svg.selectAll(".y.axis")
.data(traits)
.enter().append("g")
.attr("class", "y axis")
.attr("transform", function(d, i) { return "translate(0," + i * size + ")"; })
.each(function(d) { y.domain(domainByTrait[d]); d3.select(this).call(yAxis); });
var cell = svg.selectAll(".cell")
.data(cross(traits, traits))
.enter().append("g")
.attr("class", "cell")
.attr("transform", function(d) { return "translate(" + (n - d.i - 1) * size + "," + d.j * size + ")"; })
.each(plot);
// Titles for the diagonal.
cell.filter(function(d) { return d.i === d.j; }).append("text")
.attr("x", padding)
.attr("y", padding)
.attr("dy", ".71em")
.text(function(d) { return d.x; });
cell.call(brush);
function plot(p) {
var cell = d3.select(this);
x.domain(domainByTrait[p.x]);
y.domain(domainByTrait[p.y]);
cell.append("rect")
.attr("class", "frame")
.attr("x", padding / 2)
.attr("y", padding / 2)
.attr("width", size - padding)
.attr("height", size - padding);
cell.selectAll("circle")
.data(data)
.enter().append("circle")
.attr("cx", function(d) { return x(d[p.x]); })
.attr("cy", function(d) { return y(d[p.y]); })
.attr("r", 3)
.style("fill", function(d) { return color(d.species); });
}
var brushCell;
// Clear the previously-active brush, if any.
function brushstart(p) {
if (brushCell !== this) {
d3.select(brushCell).call(brush.clear());
x.domain(domainByTrait[p.x]);
y.domain(domainByTrait[p.y]);
brushCell = this;
}
}
// Highlight the selected circles.
function brushmove(p) {
var e = brush.extent();
svg.selectAll("circle").classed("hidden", function(d) {
return e[0][0] > d[p.x] || d[p.x] > e[1][0]
|| e[0][1] > d[p.y] || d[p.y] > e[1][1];
});
}
// If the brush is empty, select all circles.
function brushend() {
if (brush.empty()) svg.selectAll(".hidden").classed("hidden", false);
}
function cross(a, b) {
var c = [], n = a.length, m = b.length, i, j;
for (i = -1; ++i < n;) for (j = -1; ++j < m;) c.push({x: a[i], i: i, y: b[j], j: j});
return c;
}
d3.select(self.frameElement).style("height", size * n + padding + 20 + "px");
});
</script>sepal length,sepal width,petal length,petal width,species
15.1,3.5,1.4,0.2,setosa
14.9,3.0,1.4,0.2,setosa
14.7,3.2,1.3,0.2,setosa
14.6,3.1,1.5,0.2,setosa
15.0,3.6,1.4,0.2,setosa
15.4,3.9,1.7,0.4,setosa
14.6,3.4,1.4,0.3,setosa
15.0,3.4,1.5,0.2,setosa
14.4,2.9,1.4,0.2,setosa
14.9,3.1,1.5,0.1,setosa
15.4,3.7,1.5,0.2,setosa
14.8,3.4,1.6,0.2,setosa
14.8,3.0,1.4,0.1,setosa
14.3,3.0,1.1,0.1,setosa
15.8,4.0,1.2,0.2,setosa
15.7,4.4,1.5,0.4,setosa
15.4,3.9,1.3,0.4,setosa
15.1,3.5,1.4,0.3,setosa
15.7,3.8,1.7,0.3,setosa
15.1,3.8,1.5,0.3,setosa
15.4,3.4,1.7,0.2,setosa
15.1,3.7,1.5,0.4,setosa
14.6,3.6,1.0,0.2,setosa
15.1,3.3,1.7,0.5,setosa
14.8,3.4,1.9,0.2,setosa
15.0,3.0,1.6,0.2,setosa
15.0,3.4,1.6,0.4,setosa
15.2,3.5,1.5,0.2,setosa
15.2,3.4,1.4,0.2,setosa
14.7,3.2,1.6,0.2,setosa
14.8,3.1,1.6,0.2,setosa
15.4,3.4,1.5,0.4,setosa
15.2,4.1,1.5,0.1,setosa
15.5,4.2,1.4,0.2,setosa
14.9,3.1,1.5,0.2,setosa
15.0,3.2,1.2,0.2,setosa
15.5,3.5,1.3,0.2,setosa
14.9,3.6,1.4,0.1,setosa
14.4,3.0,1.3,0.2,setosa
15.1,3.4,1.5,0.2,setosa
15.0,3.5,1.3,0.3,setosa
14.5,2.3,1.3,0.3,setosa
14.4,3.2,1.3,0.2,setosa
15.0,3.5,1.6,0.6,setosa
15.1,3.8,1.9,0.4,setosa
14.8,3.0,1.4,0.3,setosa
15.1,3.8,1.6,0.2,setosa
14.6,3.2,1.4,0.2,setosa
15.3,3.7,1.5,0.2,setosa
15.0,3.3,1.4,0.2,setosa
17.0,3.2,4.7,1.4,versicolor
16.4,3.2,4.5,1.5,versicolor
16.9,3.1,4.9,1.5,versicolor
15.5,2.3,4.0,1.3,versicolor
16.5,2.8,4.6,1.5,versicolor
15.7,2.8,4.5,1.3,versicolor
16.3,3.3,4.7,1.6,versicolor
14.9,2.4,3.3,1.0,versicolor
16.6,2.9,4.6,1.3,versicolor
15.2,2.7,3.9,1.4,versicolor
15.0,2.0,3.5,1.0,versicolor
15.9,3.0,4.2,1.5,versicolor
16.0,2.2,4.0,1.0,versicolor
16.1,2.9,4.7,1.4,versicolor
15.6,2.9,3.6,1.3,versicolor
16.7,3.1,4.4,1.4,versicolor
15.6,3.0,4.5,1.5,versicolor
15.8,2.7,4.1,1.0,versicolor
16.2,2.2,4.5,1.5,versicolor
15.6,2.5,3.9,1.1,versicolor
15.9,3.2,4.8,1.8,versicolor
16.1,2.8,4.0,1.3,versicolor
16.3,2.5,4.9,1.5,versicolor
16.1,2.8,4.7,1.2,versicolor
16.4,2.9,4.3,1.3,versicolor
16.6,3.0,4.4,1.4,versicolor
16.8,2.8,4.8,1.4,versicolor
16.7,3.0,5.0,1.7,versicolor
16.0,2.9,4.5,1.5,versicolor
15.7,2.6,3.5,1.0,versicolor
15.5,2.4,3.8,1.1,versicolor
15.5,2.4,3.7,1.0,versicolor
15.8,2.7,3.9,1.2,versicolor
16.0,2.7,5.1,1.6,versicolor
15.4,3.0,4.5,1.5,versicolor
16.0,3.4,4.5,1.6,versicolor
16.7,3.1,4.7,1.5,versicolor
16.3,2.3,4.4,1.3,versicolor
15.6,3.0,4.1,1.3,versicolor
15.5,2.5,4.0,1.3,versicolor
15.5,2.6,4.4,1.2,versicolor
16.1,3.0,4.6,1.4,versicolor
15.8,2.6,4.0,1.2,versicolor
15.0,2.3,3.3,1.0,versicolor
15.6,2.7,4.2,1.3,versicolor
15.7,3.0,4.2,1.2,versicolor
15.7,2.9,4.2,1.3,versicolor
16.2,2.9,4.3,1.3,versicolor
15.1,2.5,3.0,1.1,versicolor
15.7,2.8,4.1,1.3,versicolor
6.3,3.3,6.0,2.5,virginica
5.8,2.7,5.1,1.9,virginica
7.1,3.0,5.9,2.1,virginica
6.3,2.9,5.6,1.8,virginica
6.5,3.0,5.8,2.2,virginica
7.6,3.0,6.6,2.1,virginica
4.9,2.5,4.5,1.7,virginica
7.3,2.9,6.3,1.8,virginica
6.7,2.5,5.8,1.8,virginica
7.2,3.6,6.1,2.5,virginica
6.5,3.2,5.1,2.0,virginica
6.4,2.7,5.3,1.9,virginica
6.8,3.0,5.5,2.1,virginica
5.7,2.5,5.0,2.0,virginica
5.8,2.8,5.1,2.4,virginica
6.4,3.2,5.3,2.3,virginica
6.5,3.0,5.5,1.8,virginica
7.7,3.8,6.7,2.2,virginica
7.7,2.6,6.9,2.3,virginica
6.0,2.2,5.0,1.5,virginica
6.9,3.2,5.7,2.3,virginica
5.6,2.8,4.9,2.0,virginica
7.7,2.8,6.7,2.0,virginica
6.3,2.7,4.9,1.8,virginica
6.7,3.3,5.7,2.1,virginica
7.2,3.2,6.0,1.8,virginica
6.2,2.8,4.8,1.8,virginica
6.1,3.0,4.9,1.8,virginica
6.4,2.8,5.6,2.1,virginica
7.2,3.0,5.8,1.6,virginica
7.4,2.8,6.1,1.9,virginica
7.9,3.8,6.4,2.0,virginica
6.4,2.8,5.6,2.2,virginica
6.3,2.8,5.1,1.5,virginica
6.1,2.6,5.6,1.4,virginica
6.3,3.4,5.6,2.4,virginica
6.4,3.1,5.5,1.8,virginica
6.0,3.0,4.8,1.8,virginica
6.9,3.1,5.4,2.1,virginica
6.7,3.1,5.6,2.4,virginica
6.9,3.1,5.1,2.3,virginica
5.8,2.7,5.1,1.9,virginica
6.8,3.2,5.9,2.3,virginica
6.7,3.3,5.7,2.5,virginica
6.7,3.0,5.2,2.3,virginica
6.3,2.5,5.0,1.9,virginica
6.5,3.0,5.2,2.0,virginica
6.2,3.4,5.4,2.3,virginica
5.9,3.0,5.1,1.8,virginica