@datastructures-js/graph

Graph & Directed Graph

Graph's vertex is represented as a key-value object where key data type is: number or string

Usage

const graphFn = require('@datastructures-js/graph');

// graph
const graph = graphFn();

// directed graph
const directedGraph = graphFn({ directed: true });

API

.addVertex(key, value)

adds a vertex object to the graph. Vertex object has the following api:

getKey() get the vertex key. getValue() get the vertex value. setValue(value) sets (updates) the vertex value.

// adding vertices of the graph in the diagram
graph.addVertex('v1', true);
graph.addVertex('v2', true);
graph.addVertex('v3', true);
graph.addVertex('v4', true);
graph.addVertex('v5', true);

// adding vertices of the directed graph in the diagram
directedGraph.addVertex('v1', true);
directedGraph.addVertex('v2', true);
directedGraph.addVertex('v3', true);
directedGraph.addVertex('v4', true);
directedGraph.addVertex('v5', true);

.hasVertex(key)

checks if the graph has a vertex

console.log(graph.hasVertex('v1')); // true

.removeVertex(key)

removes a vertex from the graph

graph.removeVertex('test');
graph.hasVertex('test'); // false

.addEdge(key1, key2, weight)

adds a weighted edge between two existing vertices.

// adding edges of the graph in diagram
graph.addEdge('v1', 'v2', 2);
graph.addEdge('v2', 'v3', 3);
graph.addEdge('v1', 'v3', 6);
graph.addEdge('v2', 'v4', 1);
graph.addEdge('v4', 'v3', 1);
graph.addEdge('v4', 'v5', 4);
graph.addEdge('v3', 'v5', 2);

// adding edges of the directed graph in diagram
directedGraph.addEdge('v1', 'v2', 2);
directedGraph.addEdge('v1', 'v3', 3);
directedGraph.addEdge('v1', 'v4', 1);
directedGraph.addEdge('v2', 'v4', 1);
directedGraph.addEdge('v3', 'v5', 2);
directedGraph.addEdge('v4', 'v3', 1);
directedGraph.addEdge('v4', 'v5', 4);

.hasEdge(key1, key2)

checks if the graph has an edge between two exsiting vertices

console.log(graph.hasEdge('v1', 'v2')); // true

.getWeight(key1, key2)

returns the edge's weight between two vertices

console.log(graph.getWeight('v1', 'v2')); // 2

.removeEdge(key1, key2)

removes an existing edge in the graph

graph.removeEdge('v1', 'v2');
graph.hasEdge('v1', 'v2'); // false
graph.hasEdge('v2', 'v1'); // false

.countVertices()

gets the number of vertices in the graph.

console.log(graph.countVertices()); // 5
console.log(directedGraph.countVertices()); // 5

.dfsTraverse(key, cb)

traverse the graph from a strating vertex using depth-first search and call cb for each vertex object.

graph.traverseDfs('v1', v => console.log(v.getKey(), v.getValue()));
// v1 true
// v2 true
// v3 true
// v4 true
// v5 true

.bfsTraverse(key, cb)

traverse the graph from a strating vertex using breadth-first search and call cb for each vertex object.

graph.traverseDfs('v5', v => console.log(v.getKey(), v.getValue()));
// v5 true
// v4 true
// v3 true
// v2 true
// v1 true

.traverse(key, cb, type)

traversing the graph using dfs or bfs approach. Default is bfs.

graph.traverse('v5', v => console.log(v.getKey(), v.getValue())); // bfs default
// v5 true
// v4 true
// v3 true
// v2 true
// v1 true

graph.traverse('v1', v => console.log(v.getKey(), v.getValue()), 'dfs');
// v1 true
// v2 true
// v3 true
// v4 true
// v5 true

.dfsShortestPath(key1, key2)

finds the shortest path between two vertices based on a depth-first search algorithm.

console.log(graph.findShortestPath('v1', 'v5'));
// [ ['v1', 'v2', 'v4', 'v3', 'v5'] ]

console.log(directedGraph.dfsShortestPath('v1', 'v5'));
// [['v1', 'v4', 'v3', 'v5']]

.findShortestPath(v1, v2, algorithm)

find all possible shortests paths (same weight sum) between two vertices in the graph using an algorithm.

Right now, only a DFS algorithm is implemented. so it does the same as .dfsShortestPath.

console.log(graph.findShortestPath('v1', 'v5'));
// [ ['v1', 'v2', 'v4', 'v3', 'v5'] ]

.clear()

clears all the vertices and edges in the graph.

graph.clear();
directedGraph.clear();

Build

grunt build

License

The MIT License. Full License is here