Getting started in EJ2 TypeScript Heatmap chart control

2 Jun 202324 minutes to read

This section explains the steps required to create a heat map and demonstrates the basic usage of the heat map control.

Dependencies

For using heat map, the following minimum requirements are needed.

|-- @syncfusion/ej2-heatmap
    |-- @syncfusion/ej2-base
    |-- @syncfusion/ej2-data
    |-- @syncfusion/ej2-svg-base

Installation and configuration

To start with heat map controls, you can clone the Essential JS 2 quickstartproject
and install necessary packages by using the following commands.

git clone https://github.com/syncfusion/ej2-quickstart.git quickstart
cd quickstart
npm install

Heatmap packages should be mapped in the system.config.js configuration file.

System.config({
    paths: {
        'syncfusion:': './node_modules/@syncfusion/',
    },
    map: {
        app: 'app',

        //Syncfusion packages mapping
        "@syncfusion/ej2-base": "syncfusion:ej2-base/dist/ej2-base.umd.min.js",
        "@syncfusion/ej2-data": "syncfusion:ej2-data/dist/ej2-data.umd.min.js",
        "@syncfusion/ej2-svg-base": "syncfusion:ej2-svg-base/dist/ej2-svg-base.umd.min.js",
        "@syncfusion/ej2-heatmap": "syncfusion:ej2-heatmap/dist/ej2-heatmap.umd.min.js",
    },
    packages: {
        'app': { main: 'app', defaultExtension: 'js' }
    }
});

System.import('app');

The project is preconfigured with common settings (src/styles/styles.css, system.config.js ) to start with all Essential JS 2 controls.

Adding heat map to the project

Add an HTML div element of heat map to your index.html. [src/index.html]

<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Heatmap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="node_modules/systemjs/dist/system.src.js" type="text/javascript"></script>
    <script src="system.config.js"></script>
</head>

<body>
     <!--container which is going to render the Heatmap-->
     <div id='element'>
     </div>
</body>

</html>

Now, import the heat map control into your app.ts to instantiate the heat map and append the heat map instance to the #container [src/app/app.ts]

import { HeatMap } from '@syncfusion/ej2-heatmap';

// initialize HeatMap control
let heatmap: HeatMap = new HeatMap();

// render initialized HeatMap
heatmap.appendTo('#element');

Use the npm run start command to run the application in the browser.


npm run start

The below example shows a basic Heatmap.

index.ts
index.html
import { HeatMap } from '@syncfusion/ej2-heatmap';

let heatmap: HeatMap = new HeatMap ();

heatmap.appendTo('#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

Module Injection

The heat map controls are segregated into individual feature-wise modules. To use its feature, you need to inject its feature module using the HeatMap.Inject() method. In the current application, the basic heat map is modified to visualize sales revenue data for week, and the tooltip and legend features of the heat map are used. Find the relevant feature modules and descriptions as follows.

Legend - Provides the legend feature by injecting it.
Tooltip - Provides the tooltip feature by injecting it.

Now, import the above-mentioned modules from the heat map package and inject them into the heat map control using the HeatMap.Inject() method.

import {Legend, Tooltip} from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

Populate heat map with data

This section explains how to populate the following two-dimensional array data to the heat map.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
    [73, 39, 26, 39, 94, 0],
    [93, 58, 53, 38, 26, 68],
    [99, 28, 22, 4, 66, 90],
    [14, 26, 97, 69, 69, 3],
    [7, 46, 47, 47, 88, 6],
    [41, 55, 73, 23, 3, 79],
    [56, 69, 21, 86, 3, 33],
    [45, 7, 53, 81, 95, 79],
    [60, 77, 74, 68, 88, 51],
    [25, 25, 10, 12, 78, 14],
    [25, 56, 55, 58, 12, 82],
    [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
     dataSource: heatmapData,
     }, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

Enable axis labels

You can add axis labels to the heat map and format those labels using the xAxis and yAxis properties. Axis labels provide additional information about the data points populated in the heat map.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
     [73, 39, 26, 39, 94, 0],
     [93, 58, 53, 38, 26, 68],
     [99, 28, 22, 4, 66, 90],
     [14, 26, 97, 69, 69, 3],
     [7, 46, 47, 47, 88, 6],
     [41, 55, 73, 23, 3, 79],
     [56, 69, 21, 86, 3, 33],
     [45, 7, 53, 81, 95, 79],
     [60, 77, 74, 68, 88, 51],
     [25, 25, 10, 12, 78, 14],
     [25, 56, 55, 58, 12, 82],
     [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
    xAxis: {
        labels: ['Nancy', 'Andrew','Janet', 'Margaret', 'Steven',
        'Michael', 'Robert', 'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
         },
         yAxis:{
             labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
             },
             dataSource: heatmapData
             }, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

Add heat map title

Add a title using the titleSettings property to the heat map to provide quick information to the user
about the data populated in the heat map.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
     [73, 39, 26, 39, 94, 0],
            [93, 58, 53, 38, 26, 68],
            [99, 28, 22, 4, 66, 90],
            [14, 26, 97, 69, 69, 3],
            [7, 46, 47, 47, 88, 6],
            [41, 55, 73, 23, 3, 79],
            [56, 69, 21, 86, 3, 33],
            [45, 7, 53, 81, 95, 79],
            [60, 77, 74, 68, 88, 51],
            [25, 25, 10, 12, 78, 14],
            [25, 56, 55, 58, 12, 82],
            [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
    titleSettings: {
            text: 'Sales Revenue per Employee (in 1000 US$)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        },
        xAxis: {
            labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven',
            'Michael', 'Robert', 'Laura', 'Anne', 'Paul', 'Karin',   'Mario'],
        },
        yAxis: {
            labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
        },
     dataSource: heatmapData,
     }, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

Enable legend

Use a legend for the heat map in the visible object by setting the legendSettings property to true and injecting the Legend module using the HeatMap.Inject(Legend) method.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
     [73, 39, 26, 39, 94, 0],
            [93, 58, 53, 38, 26, 68],
            [99, 28, 22, 4, 66, 90],
            [14, 26, 97, 69, 69, 3],
            [7, 46, 47, 47, 88, 6],
            [41, 55, 73, 23, 3, 79],
            [56, 69, 21, 86, 3, 33],
            [45, 7, 53, 81, 95, 79],
            [60, 77, 74, 68, 88, 51],
            [25, 25, 10, 12, 78, 14],
            [25, 56, 55, 58, 12, 82],
            [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
    titleSettings: {
            text: 'Sales Revenue per Employee (in 1000 US$)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        },
        xAxis: {
            labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven',
            'Michael', 'Robert', 'Laura', 'Anne', 'Paul', 'Karin',   'Mario'],
        },
        yAxis: {
            labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
        },
        dataSource: heatmapData,
        legendSettings: {
            visible:true,
            position: 'Right',
            showLabel: true,
            height: "150"
        }
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

Add data label

Add data labels to improve the readability of the heat map. This can be achieved by setting the showLabel property to true in the cellSettings object.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
     [73, 39, 26, 39, 94, 0],
            [93, 58, 53, 38, 26, 68],
            [99, 28, 22, 4, 66, 90],
            [14, 26, 97, 69, 69, 3],
            [7, 46, 47, 47, 88, 6],
            [41, 55, 73, 23, 3, 79],
            [56, 69, 21, 86, 3, 33],
            [45, 7, 53, 81, 95, 79],
            [60, 77, 74, 68, 88, 51],
            [25, 25, 10, 12, 78, 14],
            [25, 56, 55, 58, 12, 82],
            [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
     titleSettings: {
        text: 'Sales Revenue per Employee (in 1000 US$)',
        textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        },
     cellSettings: {
            showLabel: true,
        },
     xAxis: {
            labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven',
            'Michael', 'Robert', 'Laura', 'Anne', 'Paul', 'Karin',   'Mario'],
        },
     yAxis: {
            labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
        },
     dataSource: heatmapData,
     legendSettings: {
            position: 'Right',
            showLabel: true,
            height: "150"
     }
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

Add custom cell palette

The default palette settings of the heat map cells can be customized by using the paletteSettings property.
Using the palette property in paletteSettings object, you can change the color set for the cells.
You can change the color mode of the cells to fixed or gradient mode using the type property.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
     [73, 39, 26, 39, 94, 0],
            [93, 58, 53, 38, 26, 68],
            [99, 28, 22, 4, 66, 90],
            [14, 26, 97, 69, 69, 3],
            [7, 46, 47, 47, 88, 6],
            [41, 55, 73, 23, 3, 79],
            [56, 69, 21, 86, 3, 33],
            [45, 7, 53, 81, 95, 79],
            [60, 77, 74, 68, 88, 51],
            [25, 25, 10, 12, 78, 14],
            [25, 56, 55, 58, 12, 82],
            [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
    titleSettings: {
            text: 'Sales Revenue per Employee (in 1000 US$)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        },
    cellSettings: {
            showLabel: true,
        },
     xAxis: {
            labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven',
            'Michael', 'Robert', 'Laura', 'Anne', 'Paul', 'Karin',   'Mario'],
        },
      yAxis: {
            labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
        },
      dataSource: heatmapData,
      legendSettings: {
            position: 'Right',
            showLabel: true,
            height: "150"
        },
      paletteSettings: {
            palette: [
                { value: 0, color: '#C06C84' },
                { value: 50, color: '#6C5B7B' },
                { value: 100, color: '#355C7D' }
                ],
            type: "Gradient"
        },
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>

The tooltip is used when you cannot display information by using the data labels due to space constraints. You can enable the tooltip by setting the showTooltip property to true and injecting the Tooltip module using the HeatMap.Inject(Tooltip) method.

index.ts
index.html
import { HeatMap, Legend, Tooltip } from '@syncfusion/ej2-heatmap';
HeatMap.Inject(Legend, Tooltip);

let heatmapData: any [] = [
     [73, 39, 26, 39, 94, 0],
            [93, 58, 53, 38, 26, 68],
            [99, 28, 22, 4, 66, 90],
            [14, 26, 97, 69, 69, 3],
            [7, 46, 47, 47, 88, 6],
            [41, 55, 73, 23, 3, 79],
            [56, 69, 21, 86, 3, 33],
            [45, 7, 53, 81, 95, 79],
            [60, 77, 74, 68, 88, 51],
            [25, 25, 10, 12, 78, 14],
            [25, 56, 55, 58, 12, 82],
            [74, 33, 88, 23, 86, 59]];

let heatmap: HeatMap = new HeatMap({
    titleSettings: {
            text: 'Sales Revenue per Employee (in 1000 US$)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        },
    cellSettings: {
            showLabel: true,
        },
    xAxis: {
            labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven',
            'Michael', 'Robert', 'Laura', 'Anne', 'Paul', 'Karin',   'Mario'],
        },
    yAxis: {
            labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
        },
    dataSource: heatmapData,
    legendSettings: {
            position: 'Right',
            showLabel: true,
            height: "150"
        },
    showTooltip:true,
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 HeatMap</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='element'></div>
    </div>
</body>

</html>