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Chart.js Graphs

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Chart.js module for charting graphs. Adding new chart types: graph, forceDirectedGraph, dendogram, and tree.

force

dend_h

tree_v

radial

Works great with https://github.com/chartjs/chartjs-plugin-datalabels or https://github.com/chrispahm/chartjs-plugin-dragdata

data label

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Related Plugins

Check out also my other chart.js plugins:

Install

npm install --save chart.js chartjs-chart-graph

Usage

see Samples on Github

CodePens

Graphviz Dot File Parsing

A Graphviz Dot File parsing package is located at https://github.com/sgratzl/chartjs-chart-graph-dot-parser. It creates compatible data structures to be consumed by this plugin.

Styling

The new chart types are based on the existing line controller. Tho, instead of showing a line per dataset it shows edges as lines. Therefore, the styling options for points and lines are the same. See also https://www.chartjs.org/docs/latest/charts/line.html. However, to avoid confusion, the line options have a default line prefix, e..g lineBorderColor to specify the edge border color and pointBorderColor to specify the node border color.

Data Structure

data: {
  labels: ['A', 'B', 'C'], // node labels
  datasets: [{
    data: [ // nodes as objects
      { x: 1, y: 2 }, // x, y will be set by the force directed graph and can be omitted
      { x: 3, y: 1 },
      { x: 5, y: 3 }
    ],
    edges: [ // edge list where source/target refers to the node index
      { source: 0, target: 1},
      { source: 0, target: 2}
    ]
  }]
},

Alternative structure for trees

data: {
  labels: ['A', 'B', 'C'], // node labels
  datasets: [{
    data: [ // nodes as objects
      { x: 1, y: 2 }, // x, y will be set by the force directed graph and can be omitted
      { x: 3, y: 1, parent: 0 },
      { x: 5, y: 3, parent: 0 }
    ]
  }]
},

Force Directed Graph

chart type: forceDirectedGraph

Computes the x,y position of nodes based on a force simulation. It is based on https://github.com/d3/d3-force/.

force

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Options

Dendogram, Tree

chart types: dendogram, tree

The tree and dendograms layouts are based on https://github.com/d3/d3-hierarchy.

Dendogram Horizontal

dend_h

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Dendogram Vertical

dend_v

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Dendogram Radial

radial

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Tidy Tree Horizontal

tree_h

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Tidy Tree Vertical

tree_v

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Tidy Tree Radial

radial

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Options

ESM and Tree Shaking

The ESM build of the library supports tree shaking thus having no side effects. As a consequence the chart.js library won't be automatically manipulated nor new controllers automatically registered. One has to manually import and register them.

Variant A:

import { Chart, LinearScale, PointElement } from 'chart.js';
import { ForceDirectedGraphController, EdgeLine } from 'chartjs-chart-graph';

// register controller in chart.js and ensure the defaults are set
Chart.register(ForceDirectedGraphController, EdgeLine, LinearScale, PointElement);
...

new Chart(ctx, {
  type: ForceDirectedGraphController.id,
  data: [...],
});

Variant B:

import { ForceDirectedGraphChart } from 'chartjs-chart-graph';

new ForceDirectedGraphChart(ctx, {
  data: [...],
});

Development Environment

npm i -g yarn
yarn install
yarn sdks vscode

Building

yarn install
yarn build