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D3 barchart with axes, scales and transitions (Data: randomly generated)
license: mit
border: no
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>CMT212 Lab Week 2</title>
<link rel="stylesheet" href="../base.css">
<script src="//d3js.org/d3.v4.min.js" charset="utf-8"></script>
<style>
.labels {
fill: white;
}
</style>
</head>
<body>
<input type="button" onclick="update()" value="Update"/>
<input type="range" value="50" min="0" max="100" id="maximum">
<div id="vis">
</div>
<script src="script.js".>
</script>
</body>
</html>
var width = 500;
var height = 350;
var maxValue = d3.select('#maximum')
.node()
.value;
var margin = {
top: 20,
left: 30,
right: 30,
bottom: 30
};
var svg = d3.select("#vis")
.append("svg")
.attr('width', width)
.attr('height', height)
.append("g")
.attr("transform", "translate(" + margin.top + "," + margin.left + ")");
width = width - margin.left - margin.right;
height = height - margin.top - margin.bottom;
var yscale = d3.scaleLinear()
.range([height, 0])
.domain([0, maxValue]);
var xscale = d3.scaleBand()
.range([0, width])
.padding(0.1);
var duration = 1000;
var xaxis = d3.axisBottom(xscale);
var yaxis = d3.axisLeft(yscale);
svg.append('g')
.attr('transform', 'translate(0, ' + (height) + ')')
.attr('class', 'x axis');
svg.append('g')
.attr('class', 'y axis');
function update() {
maxValue = d3.select('#maximum')
.node()
.value;
var exampleData = createRandomData(maxValue);
maxValue = d3.max(exampleData);
xscale.domain(d3.range(exampleData.length));
yscale.domain([0, maxValue]);
var bars = svg.selectAll(".bar")
.data(exampleData);
bars
.enter()
.append('rect')
.attr('class', 'bar')
.attr("fill", "red")
.attr('width', xscale.bandwidth())
.attr('height', 0)
.attr('y', height)
.merge(bars)
.transition()
.duration(duration)
.attr("height", function(d, i) {
return height - yscale(d);
})
.attr("y", function(d, i) {
return yscale(d);
})
.attr("width", xscale.bandwidth())
.attr("x", function(d, i) {
return xscale(i);
})
bars
.exit()
.transition()
.duration(duration)
.attr('height', 0)
.attr('y', height)
.remove();
var labels = svg.selectAll('.label')
.data(exampleData);
var new_labels = labels
.enter()
.append('text')
.attr('class', 'label')
.attr('opacity', 0)
.attr('y', height)
.attr('fill', 'white')
.attr('text-anchor', 'middle')
new_labels.merge(labels)
.transition()
.duration(duration)
.attr('opacity', 1)
.attr('x', function(d, i) {
return xscale(i) + xscale.bandwidth() / 2;
})
.attr('y', function(d) {
return yscale(d) + 20;
})
.text(function(d) {
return d;
});
labels
.exit()
.transition()
.duration(duration)
.attr('y', height)
.attr('opacity', 0)
.remove();
svg.select('.x.axis')
.transition()
.duration(duration)
.call(xaxis);
svg.select('.y.axis')
.transition()
.duration(duration)
.call(yaxis);
}
function createRandomData(maxValue) {
var numDataItems = Math.floor((Math.random() * 30) + 1);
var d = [];
for (var i = 0; i < numDataItems; i++) {
d.push(Math.floor((Math.random() * maxValue) + 1));
}
return d;
}
update();
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