Skip to content

Instantly share code, notes, and snippets.

@UdochukwuNweke
Created January 27, 2018 04:54
Show Gist options
  • Star 0 You must be signed in to star a gist
  • Fork 0 You must be signed in to fork a gist
  • Save UdochukwuNweke/75e876f7025a36912a26703661238083 to your computer and use it in GitHub Desktop.
Save UdochukwuNweke/75e876f7025a36912a26703661238083 to your computer and use it in GitHub Desktop.
S18 - HW 3 - Bar Chart
license: gpl-3.0

CS 725/825 - Spring 2018 - Homework 3 - Bar Chart

See the assignment instructions at http://www.cs.odu.edu/~mweigle/CS725-S18/HW3

Explanation of how the bar chart is constructed (for the most part) is available at https://bost.ocks.org/mike/bar/3/

Other helpful links (scale, domain, range):

Original README.md

This simple bar chart is constructed from a TSV file storing the frequency of letters in the English language. The chart employs conventional margins and a number of D3 features:

forked from mbostock's block: Bar Chart

forked from weiglemc's block: S18 - HW 3 - Bar Chart

forked from anonymous's block: S18 - HW 3 - Bar Chart

forked from anonymous's block: S18 - HW 3 - Bar Chart

letter frequency
A .08167
B .01492
C .02782
D .04253
E .12702
F .02288
G .02015
H .06094
I .06966
J .00153
K .00772
L .04025
M .02406
N .06749
O .07507
P .01929
Q .00095
R .05987
S .06327
T .09056
U .02758
V .00978
W .02360
X .00150
Y .01974
Z .00074
<!DOCTYPE html>
<html>
<meta charset="utf-8">
<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="https://d3js.org/d3-scale-chromatic.v1.min.js"></script> <!-- for color scales -->
<style>
body {font-family: calibri;}
.axis {font: 14px calibri;}
.label {font: 16px calibri;}
</style>
<body>
<p>Frequency of usage of letters in English</p>
<h2>Bar Chart 1</h2>
<div><svg id="chart1" width="800" height="400"></svg></div>
<h2>Bar Chart 2</h2>
<div><svg id="chart2" width="800" height="400"></svg></div>
<script>
// chart 1
var svg1 = d3.select("#chart1"),
margin = {top: 20, right: 20, bottom: 30, left: 40},
width = +svg1.attr("width") - margin.left - margin.right,
height = +svg1.attr("height") - margin.top - margin.bottom;
// See https://github.com/d3/d3-scale
var x1 = d3.scaleBand().rangeRound([0, width]).padding(0.1),
y1 = d3.scaleLinear().rangeRound([height, 0]); // note that we've reversed the range
// creates new svg <g> space, sets new (0,0) at left, top margin
var g1 = svg1.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
d3.tsv("data.tsv", function(d) {
d.frequency = +d.frequency; // convert text to number
return d;
}, function(error, data) {
if (error) throw error;
// See https://www.dashingd3js.com/d3js-scales
// maps domain of x values (letters) to range of positions on x-axis
x1.domain(data.map(function(d) { return d.letter; }));
// maps domain of y values (frequencies 0, max freq) to range of positions on y-axis
y1.domain([0, d3.max(data, function(d) { return d.frequency; })]);
// x-axis
g1.append("g")
.attr("class", "axis x-axis")
.attr("transform", "translate(0," + height + ")") // move axis to bottom of chart
.call(d3.axisBottom(x1));
// y-axis
g1.append("g")
.attr("class", "axis y-axis")
.call(d3.axisLeft(y1).ticks(10, "#")); // number of ticks and type
// y-axis label
g1.append("text")
.attr("class", "label")
.attr("x", 0-margin.left) // set x position of label
.attr("y", 0-margin.top/2) // set y position of label
.style("text-anchor", "start") // left-justify
.text ("Frequency")
// bars
g1.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function(d) { console.log ("letter: " + d.letter + ", x: " + x1(d.letter)); return x1(d.letter); })
.attr("y", function(d) { console.log ("freq: " + d.frequency + ", y: " + y1(d.frequency)); return y1(d.frequency); })
.attr("width", x1.bandwidth()) // width of each band
.attr("height", function(d) { return height - y1(d.frequency); })
.style("fill", "steelblue") // color of the bars
;
});
// chart 2
var svg2 = d3.select("#chart2"),
margin = {top: 20, right: 20, bottom: 30, left: 40},
width = +svg2.attr("width") - margin.left - margin.right,
height = +svg2.attr("height") - margin.top - margin.bottom;
var x2 = d3.scaleBand().rangeRound([0, width]).padding(0.1),
y2 = d3.scaleLinear().rangeRound([height, 0]);
var g2 = svg2.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
d3.tsv("data.tsv", function(d) {
d.frequency = +d.frequency;
return d;
}, function(error, data) {
if (error) throw error;
x2.domain(data.map(function(d) { return d.letter; }));
y2.domain([0, d3.max(data, function(d) { return d.frequency; })]);
// x-axis
g2.append("g")
.attr("class", "axis axis--x")
.attr("transform", "translate(0," + height + ")")
.call(d3.axisBottom(x2));
// y-axis
g2.append("g")
.attr("class", "axis axis--y")
.call(d3.axisLeft(y2).ticks(10, "#"));
// y-axis label
g2.append("text")
.attr("class", "label")
.attr("x", 0-margin.left)
.attr("y", 0-margin.top/2)
.style("text-anchor", "begin")
.text ("Frequency")
// bars
g2.selectAll(".bar")
.data(data)
.enter().append("rect")
.attr("class", "bar")
.attr("x", function(d) { return x2(d.letter); })
.attr("y", function(d) { return y2(d.frequency); })
.attr("width", x2.bandwidth())
.attr("height", function(d) { return height - y2(d.frequency); })
.style("fill", "teal") // color of the bars
;
});
</script>
</body>
</html>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment