bugl
bugl
HomeLearnPatternsSearch
HomeLearnPatternsSearch

Loading lesson path

Learn/AI/JS Graphics
AI•JS Graphics

Chart.js

Concept visual

Chart.js

Graph traversalgraph
ABCDE
current
queued
1
4

Start from A

Formula

Chart.js is a free JavaScript library for making HTML - based charts.
It is one of the simplest visualization libraries for JavaScript, and comes with the following built - in chart types:

Scatter Plot

Line Chart

Bar Chart

Pie Chart

Donut Chart

Bubble Chart

Area Chart

Radar Chart

Mixed Chart

How to Use Chart.js? Chart.js is easy to use. First, add a link to the providing CDN (Content Delivery Network):

Formula

< script src ="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.4/Chart.js">

</script>

Formula

Then, add a < canvas > to where you want to draw the chart:
<canvas id="myChart" style="width:100%;max-width:700px"></canvas>

The canvas element must have a unique id. That's all!

Typical Scatter Chart Syntax:

const myChart = new Chart("myChart", {
type: "scatter", data: {}, options: {}
});

Typical Line Chart Syntax:

const myChart = new Chart("myChart", {
type: "line", data: {}, options: {}
});

Typical Bar Chart Syntax:

const myChart = new Chart("myChart", {
type: "bar", data: {}, options: {}
});

Scatter Plots

House Prices vs. Size

Source Code const xyValues = [
{x:50, y:7},
{x:60, y:8},
{x:70, y:8},
{x:80, y:9},
{x:90, y:9},
{x:100, y:9},
{x:110, y:10},
{x:120, y:11},
{x:130, y:14},
{x:140, y:14},
{x:150, y:15}
];
new Chart("myChart", {
type: "scatter", data: {
datasets: [{
pointRadius: 4, pointBackgroundColor: "rgba(0,0,255,1)", data: xyValues
}]
}, options:{...}
});

Line Graphs

House Prices vs. Size

Source Code const xValues = [50,60,70,80,90,100,110,120,130,140,150];
const yValues = [7,8,8,9,9,9,10,11,14,14,15];
new Chart("myChart", {
type: "line", data: {
labels: xValues, datasets: [{
backgroundColor:"rgba(0,0,255,1.0)", borderColor: "rgba(0,0,255,0.1)", data: yValues
}]
}, options:{...}
});

If you set the borderColor to zero, you can scatter plot the line graph: borderColor: "rgba(0,0,0,0)",

Multiple Lines

Source Code const xValues = [100,200,300,400,500,600,700,800,900,1000];
new Chart("myChart", {
type: "line", data: {
labels: xValues, datasets: [{
data: [860,1140,1060,1060,1070,1110,1330,2210,7830,2478], borderColor: "red", fill: false
},{
data: [1600,1700,1700,1900,2000,2700,4000,5000,6000,7000], borderColor: "green", fill: false
},{
data: [300,700,2000,5000,6000,4000,2000,1000,200,100], borderColor: "blue", fill: false
}]
}, options: {
legend: {display: false}
}
});

Linear Graphs

Source Code const xValues = [];
const yValues = [];
generateData("x * 2 + 7", 0, 10, 0.5);
new Chart("myChart", {
type: "line", data: {
labels: xValues, datasets: [{
fill: false, pointRadius: 1, borderColor: "rgba(255,0,0,0.5)", data: yValues
}]
}, options: {...}
});
function generateData(value, i1, i2, step = 1) {
for (let x = i1; x <= i2; x += step) {
yValues.push(eval(value));
xValues.push(x);
}
}

Function Graphs

Same as Linear Graph. Just change the generateData parameter(s):

generateData("Math.sin(x)", 0, 10, 0.5);

Bar Charts

Source Code var xValues = ["Italy", "France", "Spain", "USA", "Argentina"];
var yValues = [55, 49, 44, 24, 15];
var barColors = ["red", "green","blue","orange","brown"];
new Chart("myChart", {
type: "bar", data: {
labels: xValues, datasets: [{

backgroundColor: barColors, data: yValues

}]
}, options: {...}
});

Color only one bar:

var barColors = ["blue"];

Same color all bars:

var barColors ="red";

Color Shades:

var barColors = [
"rgba(0,0,255,1.0)",
"rgba(0,0,255,0.8)",
"rgba(0,0,255,0.6)",
"rgba(0,0,255,0.4)",
"rgba(0,0,255,0.2)",
];

Horizontal Bars

Just change type from "bar" to "horizontalBar": type: "horizontalBar",

Pie Charts

Example new Chart("myChart", {
type: "pie", data: {
labels: xValues, datasets: [{

backgroundColor: barColors, data: yValues

}]
}, options: {
title: {
display: true, text: "World Wide Wine Production"
}
}
});

Previous

Plotly.js

Next

Google Chart