Graph generators

This module generates various graphs. It is part of larger ngraph family. If you need something not as simple as generated graphs, please check out ngraph.sparce-collection repository which contains graphs from University of Florida collection.

Install

With npm do:

npm install ngraph.generators

If you prefer CDN you can also do:

<script src='https://cdn.jsdelivr.net/npm/[email protected]/dist/ngraph.generators.min.js'></script>

In case of CDN the library will be accessible under global name generators

Supported graphs

All images below are clickable and point to interactive 3d visualization, done by ngraph.three library.

ladder

// Creates a ladder with 10 steps
var graph = require('ngraph.generators').ladder(10);

complete

// Creates complete graph K6
var graph = require('ngraph.generators').complete(6);

completeBipartite

// Creates complete bipartite graph K 3,3.
var graph = require('ngraph.generators').completeBipartite(3, 3);

balancedBinTree

// Creates balanced binary tree with n levels.
var graph = require('ngraph.generators').balancedBinTree(5);

path

// Generates a path-graph with 10 steps.
var graph = require('ngraph.generators').path(10);

circularLadder

// Generates a graph in a form of a circular ladder with 5 steps.
var graph = require('ngraph.generators').circularLadder(5);

grid

// Generates a graph in a form of a grid with 10 rows and 10 columns.
var graph = require('ngraph.generators').grid(10, 10);

grid3

// Generates a graph in a form of a 3d grid with 5 rows and 5 columns and 5 levels.
var graph = require('ngraph.generators').grid3(5, 5, 5);

noLinks

// Creates graph with 100 nodes and 0 links
var graph = require('ngraph.generators').noLinks(100);

cliqueCircle

var cliqueCount = 10;
var cliqueSize = 5;

// create a circle, with `cliqueCount` nodes. Each node is a fully connected
// graph with `cliqueSize` nodes
var graph = require('ngraph.generators').cliqueCircle(cliqueCount, cliqueSize);

WattsStrogatz

This is a "small world" random graph, generated by Watts and Strogatz model. In this model generator takes three arguments:

• n - number of nodes
• k - number of edges for each node. Originally node is connected with k nearest neighbours on a circle graph
• b - probability of an edge rewrite. In other words node changes it's nearest neighbor to a random node inside graph with probability b.

// Creates graph with 100 nodes, each node is connected with 20 neighbours,
// and probability of neighbour to be outside of local node community is 1%.
var g1 = require('ngraph.generators').wattsStrogatz(100, 20, 0.00);
var g2 = require('ngraph.generators').wattsStrogatz(100, 20, 0.01);
var g3 = require('ngraph.generators').wattsStrogatz(100, 20, 0.10);
var g4 = require('ngraph.generators').wattsStrogatz(100, 20, 0.50);
var g5 = require('ngraph.generators').wattsStrogatz(20, 4, 0.02);

Watts Strogatz n = 100 k = 20 b = 0.00 (g1):

Watts Strogatz n = 100 k = 20 b = 0.01 (g2):

Watts Strogatz n = 100 k = 20 b = 0.10 (g3):

Watts Strogatz n = 100 k = 20 b = 0.50 (g4):

Watts Strogatz n = 20 k = 04 b = 0.02 (g5):

Custom createGraph()

By default this library uses ngraph.graph module to create new instances of a graph. If you want to use your own module, you can use factory method:

var generate = require('ngraph.generators').factory(function createGraph() {
  // the following methods are required from the createGraph api:
  return {
    addLink(from, to) {
      // ...
    },
    addNode(nodeId) {
    },
    getNodesCount() {
    }
  }
});

// now generators have the same methods as regular ngraph.generators:
var graph = generate.ladder(3);
generate.grid(10, 10);
generate.balancedBinTree(4);
// etc.