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<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<title>d3.js ~ Three Little Circles</title>
<script type="text/javascript" src="css/d3.v2.js?2.8.1"></script>
<style type="text/css">
@import url("css/style.css?1.10.0");
@import url("css/syntax.css?1.6.0");
</style>
</head>
<body>
<div class="body">
<div class="content">
<div class="topbar">
<a href="">Overview</a>
<a href="../ex/">Examples</a>
<b><a href="../api/">Documentation</a></b>
<a href="http://github.com/mbostock/d3/archives/master">Download</a>
</div>
<div class="sidebar">
<h1>d3.js</h1>
</div>
<h1 id='three_little_circles'>Three Little Circles</h1>
<style type='text/css'>
.chart {
background: #fff;
border: solid 1px #ddd;
box-shadow: 0 0 4px rgba(0, 0, 0, .2);
font: 10px sans-serif;
height: 180px;
position: relative;
width: 720px;
}
.chart svg {
border-left: solid 2px #ddd;
left: 360px;
position: absolute;
top: 0;
}
.chart pre {
font: 12px monospace;
height: 60px;
left: 10px;
position: absolute;
top: 0;
width: 340px;
}
.chart circle.little {
fill: #aaa;
stroke: #666;
stroke-width: 1.5px;
}
.chart button {
left: 275px;
position: absolute;
top: 145px;
width: 88px;
}
.chart .data rect {
fill: #eee;
stroke: #ccc;
}
<!---some comments--->
</style>
<script type='text/javascript'>
var data = [32, 57, 112],
dataEnter = data.concat(293),
dataExit = data.slice(0, 2),
w = 360,
h = 180,
x = d3.scale.ordinal().domain([57, 32, 112]).rangePoints([0, w], 1),
y = d3.scale.ordinal().domain(data).rangePoints([0, h], 2);
</script>
<p>Once upon a time, there were three little circles. This tutorial shows you how to manipulate them using
selections.</p>
<h2 id='selecting_elements'>Selecting Elements</h2>
<p>The <a href='https://github.com/mbostock/d3/wiki/Selections#selectAll'>selectAll</a> operator takes a <a
href='http://www.w3.org/TR/CSS2/selector.html'>selector</a> string, such as “circle”, and returns a
selection:</p>
<div class='chart' id='chart-2'>
<pre class='code'>
var circle = svg.selectAll("circle");
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-2").append("svg")
.attr("width", w)
.attr("height", h);
svg.selectAll(".little")
.data(data)
.enter().append("circle")
.attr("class", "little")
.attr("cx", x)
.attr("cy", y)
.attr("r", 12);
d3.select("#chart-2 button").on("click", function () {
svg.selectAll(".select").remove();
svg.selectAll(".select")
.data(data)
.enter().append("circle")
.attr("class", "select")
.attr("cx", x)
.attr("cy", y)
.attr("r", 60)
.style("fill", "none")
.style("stroke", "red")
.style("stroke-opacity", 1e-6)
.style("stroke-width", 3)
.transition()
.duration(750)
.attr("r", 12)
.style("stroke-opacity", 1);
});
})();
</script>
<p>Once we have a selection, we can apply various operators to the selected elements. For example, we might change the
fill color using <a href='https://github.com/mbostock/d3/wiki/Selections#style'>style</a>, and the radius and the
<em>y</em>-position using <a href='https://github.com/mbostock/d3/wiki/Selections#attr'>attr</a>:</p>
<div class='chart' id='chart-3'>
<pre class='code'>
circle.style("fill", "steelblue");
circle.attr("cy", 150);
circle.attr("r", 30);
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-3").append("svg")
.attr("width", w)
.attr("height", h);
var circle = svg.selectAll(".little")
.data(data)
.enter().append("circle")
.attr("class", "little")
.attr("cx", x)
.attr("cy", y)
.attr("r", 12);
d3.select("#chart-3 button").on("click", function () {
circle.style("fill", "#aaa").attr("r", 12).attr("cy", y);
circle.transition().duration(500).delay(0).style("fill", "steelblue");
circle.transition().duration(500).delay(500).attr("cy", 150);
circle.transition().duration(500).delay(1000).attr("r", 30);
});
})();
</script>
<p>We can also compute the attribute values dynamically, using functions rather than constants. For example, maybe we
want to set the <em>x</em>-coordinate to a random value:</p>
<div class='chart' id='chart-4'>
<pre class='code'>
circle.attr("cx", function() {
return Math.random() * w;
});
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-4").append("svg")
.attr("width", w)
.attr("height", h);
var circle = svg.selectAll(".little")
.data(data)
.enter().append("circle")
.attr("class", "little")
.attr("cx", x)
.attr("cy", y)
.attr("r", 12);
d3.select("#chart-4 button").on("click", function () {
circle.transition()
.duration(750)
.attr("cx", function () {
return Math.random() * w;
});
});
})();
</script>
<p>If you run this example multiple times, you’ll see that the attribute is recomputed as a number random number
each time. Unlike Protovis, D3 doesn’t stash these functions internally; they are run once, immediately, and
then your code continues. So you can run them again or redefine them however you like.</p>
<h2 id='binding_data'>Binding Data</h2>
<p>This is beginning to look a lot like <a href='http://jquery.com/'>jQuery</a>. More commonly, though, we want to use
<em>data</em> to drive the appearance of our circles. To do that, we need some data. For the sake of example, let’s
imagine that each of these circles represents a number: 32, 57 and 112. The <a
href='https://github.com/mbostock/d3/wiki/Selections#data'>data</a> operator binds these numbers to the
circles:</p>
<div class='chart' id='chart-5'>
<pre class='code'>
circle.data([32, 57, 112]);
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-5").append("svg")
.attr("width", w)
.attr("height", h);
svg.selectAll(".little")
.data(data)
.enter().append("circle")
.attr("class", "little")
.attr("cx", x)
.attr("cy", y)
.attr("r", 12);
var g = svg.selectAll(".data")
.data(data)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-5 button").on("click", function () {
g
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
})
.select("rect")
.style("opacity", 1);
g.transition()
.duration(750)
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
})
.select("rect")
.style("opacity", 1e-6);
});
})();
</script>
<p>All data in D3 is specified as an array of values. Conveniently, this mirrors the concept of a selection, which is
just an array of elements. Notice then how the first number (the first <em>datum</em>, 32) is bound to the first
circle (the first <em>element</em>, on top), the second number is bound to the second circle, and so on.</p>
<p>Once data is bound, that data is accessible as an argument to our attribute and style functions. This means we
visually encode data, or in other words, create a visualization! For example, here we set the <em>x</em>-position
and radius using the data:</p>
<div class='chart' id='chart-6'>
<pre class='code'>
circle.attr("cx", function(d) {
return d;
});
circle.attr("r", function(d) {
return Math.sqrt(d);
});
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-6").append("svg")
.attr("width", w)
.attr("height", h);
var g = svg.selectAll("g")
.data(data)
.enter().append("g")
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
});
g.append("circle")
.attr("class", "little")
.attr("r", 12);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-6 button").on("click", function () {
g
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
})
.select("circle")
.attr("r", 12);
g.transition()
.duration(750)
.attr("transform", function (d) {
return "translate(" + d + "," + y(d) + ")";
})
.select("circle")
.attr("r", Math.sqrt);
});
})();
</script>
<p>There’s a second argument to each function you can use: it specifies the <em>index</em> of the element within
its selection. This is a <a href='http://en.wikipedia.org/wiki/Zero-based_numbering'>zero-based</a> index, and it’s
useful for computing offsets or as a simple way of identifying individual elements. The argument is optional; if you
don’t specify it when declaring your function, it will be ignored. For example:</p>
<div class='chart' id='chart-6b'>
<pre class='code'>
circle.attr("cx", function(d, i) {
return i * 100 + 30;
});
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-6b").append("svg")
.attr("width", w)
.attr("height", h);
var g = svg.selectAll("g")
.data(data)
.enter().append("g")
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
});
g.append("circle")
.attr("class", "little")
.attr("r", 12);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(function (d, i) {
return i;
});
d3.select("#chart-6b button").on("click", function () {
g
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
})
.transition()
.duration(750)
.attr("transform", function (d, i) {
return "translate(" + (i * 100 + 30) + "," + y(d) + ")";
});
});
})();
</script>
<p>Here we use the index <em>i</em> to position the elements sequentially only the <em>x</em>-dimension. Each element is
separated by 100 pixels, with an offset of 30 pixels from the left side. In SVG, the origin is in the top-left
corner.</p>
<h2 id='creating_elements'>Creating Elements</h2>
<p>But what if we had <em>four</em> numbers to display, rather than three? We wouldn’t have enough circles to
display all the numbers. When joining data to elements, D3 stores the leftover data in the <a
href='https://github.com/mbostock/d3/wiki/Selections#enter'>enter</a> selection. (The terms “enter”
and “exit” are adopted from stage terminology.) Here, the fourth number 293 remains in the enter
selection, because we only have three circle elements:</p>
<div class='chart' id='chart-7'>
<pre class='code'>
var circle = svg.selectAll("circle")
.data([32, 57, 112, 293]);
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-7").append("svg")
.attr("width", w)
.attr("height", h);
svg.selectAll(".little")
.data(data)
.enter().append("circle")
.attr("class", "little")
.attr("cx", x)
.attr("cy", y)
.attr("r", 12);
var g = svg.selectAll(".data")
.data(dataEnter)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-7 button").on("click", function () {
g
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
})
.select("rect")
.style("opacity", 1);
g.filter(
function (d, i) {
return i != 3;
}).transition()
.duration(750)
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
})
.select("rect")
.style("opacity", 1e-6);
g.select("rect").filter(function (d, i) {
return i == 3;
})
.style("fill", "#eee")
.style("stroke", "#ccc")
.transition()
.duration(750)
.style("fill", "lightgreen")
.style("stroke", "green");
});
})();
</script>
<p>Using the enter selection, we can create new circles for any missing data. Each new circle is already bound to the
data, so we can use data to compute attributes and styles:</p>
<div class='chart' id='chart-8'>
<pre class='code'>
var enter = circle.enter().append("circle");
enter.attr("cy", 90);
enter.attr("cx", 160);
enter.attr("r", function(d) {
return Math.sqrt(d);
});
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-8").append("svg")
.attr("width", w)
.attr("height", h);
var g = svg.selectAll("g")
.data(data)
.enter().append("g")
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
});
g.append("circle")
.attr("class", "little")
.attr("r", 12);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
var g = svg.selectAll(".data")
.data(dataEnter)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
})
.filter(function (d, i) {
return i == 3;
});
g.append("circle")
.attr("class", "little")
.attr("r", 1e-6);
g.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20)
.style("fill", "lightgreen")
.style("stroke", "green");
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-8 button").on("click", function () {
g.attr("transform", "translate(80,20)");
g.select("circle").attr("r", 1e-6);
g.select("rect").style("opacity", 1);
var t = g.transition().duration(750);
t.attr("transform", "translate(160,100)");
t.select("circle").attr("r", Math.sqrt);
t.select("rect").style("opacity", 1e-6);
});
})();
</script>
<p>Taking this to the next logical step, then, what if we have <em>no</em> existing elements? Meaning, what if the
document is empty? Say we start with an empty page, and we want to create new circles that correspond to our data?
Then we’re joining data to an empty selection, and all of the data ends up in <em>enter</em>:</p>
<div class='chart' id='chart-9'>
<pre class='code'>
var enter = circle.enter().append("circle");
enter.attr("cy", 90);
enter.attr("cx", function(d) {
return d;
});
enter.attr("r", function(d) {
return Math.sqrt(d);
});
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-9").append("svg")
.attr("width", w)
.attr("height", h);
var g = svg.selectAll(".data")
.data(dataEnter)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.append("circle")
.attr("class", "little")
.attr("r", 1e-6);
g.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20)
.style("fill", "lightgreen")
.style("stroke", "green");
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-9 button").on("click", function () {
g.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.select("rect").style("opacity", 1);
g.select("circle").attr("r", 1e-6);
var t = g.transition().duration(750);
t.attr("transform", function (d, i) {
return "translate(" + d + ",90)";
});
t.select("circle").attr("r", Math.sqrt);
t.select("rect").style("opacity", 1e-6);
});
})();
</script>
<p>This pattern is so common, you’ll often see the <a
href='https://github.com/mbostock/d3/wiki/Selections#selectAll'>selectAll</a> + <a
href='https://github.com/mbostock/d3/wiki/Selections#data'>data</a> + <a
href='https://github.com/mbostock/d3/wiki/Selections#enter'>enter</a> + <a
href='https://github.com/mbostock/d3/wiki/Selections#append'>append</a> operators called sequentially, one
immediately after the other. Despite it being common, keep in mind that this is just one special case of a data
join; we’ve already seen another common case (selecting elements for update) and we’ll see other
interesting cases to consider in a bit.</p>
<p>Another technique you can use to make your code more concise is <a
href='http://en.wikipedia.org/wiki/Method_chaining'>method chaining</a>. Each operator in D3 returns the current
selection, so you can apply multiple operators sequentially. For example, the above code can be rewritten:</p>
<div class='chart' id='chart-10'>
<pre class='code'>
svg.selectAll("circle")
.data([32, 57, 112, 293])
.enter().append("circle")
.attr("cy", 90)
.attr("cx", String)
.attr("r", Math.sqrt);
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-10").append("svg")
.attr("width", w)
.attr("height", h);
var g = svg.selectAll(".data")
.data(dataEnter)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.append("circle")
.attr("class", "little")
.attr("r", 1e-6);
g.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20)
.style("fill", "lightgreen")
.style("stroke", "green");
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-10 button").on("click", function () {
g.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.select("rect").style("opacity", 1);
g.select("circle").attr("r", 1e-6);
var t = g.transition().duration(750);
t.attr("transform", function (d, i) {
return "translate(" + d + ",90)";
});
t.select("circle").attr("r", Math.sqrt);
t.select("rect").style("opacity", 1e-6);
});
})();
</script>
<p>As you can see, the code is made even smaller using built-in JavaScript functions, rather than defining anonymous
ones. The built-in <a href='https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String'>String</a>
method, for example, is a shorthand way of using JavaScript’s default string conversion to compute the
attribute value from the associated data. Similarly, we can plug in <a
href='https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Math/sqrt'>Math.sqrt</a> to set
the radius attribute as the square root of the associated data. This technique of plugging in reusable functions to
compute attribute values is used extensively in D3, particularly in conjunction with <a
href='https://github.com/mbostock/d3/wiki/Quantitative-Scales'>scales</a> and <a
href='https://github.com/mbostock/d3/wiki/SVG-Shapes'>shapes</a>.</p>
<h2 id='destroying_elements'>Destroying Elements</h2>
<p>Sometimes you have the opposite problem from creation: you have too <em>many</em> existing elements, and you want to
remove them. You can select nodes and <a href='https://github.com/mbostock/d3/wiki/Selections#remove'>remove</a>
them, but more commonly, you’ll use the <a href='https://github.com/mbostock/d3/wiki/Selections#exit'>exit</a>
selection to let D3 determine which elements are exiting the stage. The exit selection is the opposite of the enter
selection: it contains all elements for which there is no corresponding data.</p>
<div class='chart' id='chart-11'>
<pre class='code'>
var circle = svg.selectAll("circle")
.data([32, 57]);
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-11").append("svg")
.attr("width", w)
.attr("height", h);
var circle = svg.selectAll(".little")
.data(data)
.enter().append("circle")
.attr("class", "little")
.attr("cx", x)
.attr("cy", y)
.attr("r", 12)
.filter(function (d, i) {
return i == 2;
});
var g = svg.selectAll(".data")
.data(dataExit)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
g.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
d3.select("#chart-11 button").on("click", function () {
g
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
})
.select("rect")
.style("opacity", 1);
g.transition()
.duration(750)
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
})
.select("rect")
.style("opacity", 1e-6);
circle
.style("fill", "#aaa")
.style("stroke", "#666")
.transition()
.duration(750)
.style("fill", "lightcoral")
.style("stroke", "red");
});
})();
</script>
<p>All that’s left to do, then, is to remove the exiting elements:</p>
<div class='chart' id='chart-12'>
<pre class='code'>
circle.exit().remove();
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-12").append("svg")
.attr("width", w)
.attr("height", h);
var g = svg.selectAll(".data")
.data(data)
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d) {
return "translate(" + x(d) + "," + y(d) + ")";
});
g.append("circle")
.attr("class", "little")
.attr("r", 12);
g.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
g = g.filter(function (d, i) {
return i == 2;
});
g.select("circle")
.style("fill", "lightcoral")
.style("stroke", "red");
d3.select("#chart-12 button").on("click", function () {
g.select("circle").attr("r", 12);
g.select("text").style("opacity", 1);
var t = g.transition().duration(750);
t.select("circle").attr("r", 1e-6);
t.select("text").style("opacity", 1e-6);
});
})();
</script>
<p>The enter, update and exit selections are computed by the <a
href='https://github.com/mbostock/d3/wiki/Selections#data'>data</a> operator, and don’t change when you
append or remove elements—at least until you call <a
href='https://github.com/mbostock/d3/wiki/Selections#selectAll'>selectAll</a> again. So, if you keep
variables around that point to selections (such as <code>circle</code>, above), you’ll probably want to
reselect after adding or removing elements.</p>
<h2 id='all_together_now'>All Together Now</h2>
<p>Putting everything together, consider the three possible outcomes that result from joining data to elements:</p>
<ol>
<li>enter - incoming actors, entering the stage.</li>
<li>update - persistent actors, staying on stage.</li>
<li>exit - outgoing actors, exiting the stage.</li>
</ol>
<p>When we use the default join-by-index, either the enter or exit selection will be empty (or both): if there are more
data than elements, the extra data are in the enter selection; if there are fewer data than elements, the extra
elements are in the exit selection. However, by specifying a key function to the data operator, we can control
exactly how data is bound to elements. And in this case, we have both enter and exit.</p>
<div class='chart' id='chart-13'>
<pre class='code'>
var circle = svg.selectAll("circle")
.data([32, 57, 293], String);
circle.enter().append("circle")
.attr("cy", 90)
.attr("cx", String)
.attr("r", Math.sqrt);
circle.exit().remove();
</pre>
<button>Run</button>
</div>
<script type='text/javascript'>
(function () {
var svg = d3.select("#chart-13").append("svg")
.attr("width", w)
.attr("height", h);
var gd = svg.selectAll(".data")
.data([32, 57, 293])
.enter().append("g")
.attr("class", "data")
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
});
var ed = gd.filter(function (d, i) {
return i == 2;
}),
ud = gd.filter(function (d, i) {
return i != 2;
});
ed.append("circle")
.attr("class", "little")
.attr("r", 1e-6);
gd.append("rect")
.attr("x", -10)
.attr("y", -10)
.attr("width", 20)
.attr("height", 20);
gd.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
var ge = svg.selectAll(".element")
.data(data)
.enter().append("g")
.attr("class", "element")
.attr("transform", function (d) {
return "translate(" + d + ",90)";
});
ge.append("circle")
.attr("class", "little")
.attr("r", Math.sqrt);
ge.append("text")
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(String);
ed.select("rect")
.style("fill", "lightgreen")
.style("stroke", "green");
var xe = ge.filter(function (d, i) {
return i == 2;
});
xe.select("circle")
.style("fill", "lightcoral")
.style("stroke", "red");
d3.select("#chart-13 button").on("click", function () {
gd
.attr("transform", function (d, i) {
return "translate(" + 20 * (i + 1) + ",20)";
})
.transition()
.duration(750)
.attr("transform", function (d) {
return "translate(" + d + ",90)";
});
gd.select("rect")
.style("opacity", 1)
.transition()
.duration(750)
.style("opacity", 1e-6);
ed.select("circle")
.attr("r", 1e-6)
.transition()
.duration(750)
.attr("r", Math.sqrt);
xe.select("circle")
.attr("r", Math.sqrt)
.transition()
.duration(750)
.attr("r", 1e-6);
xe.select("text")
.style("opacity", 1)
.transition()
.duration(750)
.style("opacity", 1e-6);
});
})();
</script>
<p>Want to learn more about selections and transitions? Read <a href='bar-2.html'>A Bar Chart, Part 2</a> for a
practical example of using enter and exit to display realtime data.</p>
</div>
<div class="foot">Copyright © 2011 <a href="http://bost.ocks.org/mike">Mike Bostock</a></div>
</div>
</div>
</body>
</html>