easy-graph

A graph/network library that has easy-to-use API to generate, manipulate and visualize graph!

• Why I wrap another library (Cytoscape.js in this case)
  • I dont like their APIs, I prefer networkX and graphStream's API
  • Dependency Inversion Principle, High level modules should not depend upon low-level modules, both should depend upon abstractions. Since abstraction changed less than implementing details.
  • With abstraction, if Cytoscape.js updates, I only need to change one copy of code, that is the easy-graph wrapper.

Quick Start

Show me the code [Dijkstra Shortest Path]

• //generate a random undirected graph, by default node has integer ID from 0
  const eg = require('easy-graph')
  const G = eg.randomGraph({v:30, p:0.5, weightOnEdge: true});
  
  const dist,prev = Array(30).fill(-Infinity), Array(30).fill(null)
  const [source,target] = [0,29]
  dist[source] = 0
  //operations on nodes and edges
  const heap = new PriorityQueue(G.V(),dist)
  while(!heap.empty()){
      let u = heap.extractMin()
      for ( v of G.Neighbor(u) ){ 
          let alt = dist[u] + G.E(u,v).weight
          if ( dist[v] > alt ) {
              dist[v] = alt
              prev[v] = u
              heap.decreaseKey(v,alt)
          }
      }
  }
  let t = target, path = [t]
  while(prev[t]){
      t = prev[t]
      path.push(t)
  }
  console.log( dist[target], path.reverse() )

Installation

• ​

API Documentation

• create a graph
  • let G = easyGraph.randomGraph()
• get all nodes id as array of nodeid [ id1, id2,...]
  • G.V()
• get all edges id as array of [ [from,to], ... ]
  • G.E()
• get adjcent nodes of a node
  • G.Neighbor(nodeID)
• get an edge object
  • G.E(sourceID, targetID)
• get a node object
  • G.V(nodeID)
• get all edges start with a node (out degree)
  • G.E(sourceID)
• ​