Chart.js

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

How to Use Chart.js?

1. Add a link to the providing CDN (Content Delivery Network):

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

2. Add a to where in the HTML you want to draw the chart:

The canvas element must have a unique id.

Typical Bar Chart Syntax:

const myChart = new Chart("myChart", <
type: "bar",
data: <>,
options: <>
>);

Typical Line Chart Syntax:

const myChart = new Chart("myChart", <
type: "line",
data: <>,
options: <>
>);

Bar Charts

Source Code

const xValues = ["Italy", "France", "Spain", "USA", "Argentina"];
const yValues = [55, 49, 44, 24, 15];
const barColors = ["red", "green","blue","orange","brown"];

new Chart("myChart", type: "bar",
data: labels: xValues,
datasets: [ backgroundColor: barColors,
data: yValues
>]
>,
options: <. >
>);

Color only one bar:

const barColors = ["blue"];

Same color all bars:

const barColors ="red";

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"
>
>
>);

Doughnut Charts

Just change type from "pie" to "doughnut":

type: "doughnut";

Scatter Plots

House Prices vs. Size

Source Code

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:
>
>);

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

Function Graphs

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