gograph

Table of Contents

• Install
• How to Use
  • Graph
    • Directed
    • Acyclic
    • Undirected
    • Weighted
  • Traverse
  • Connectivity
  • Shortest Path
    • Dijkstra
    • Bellman-Ford
    • Floyd-Warshall
• License

Install

Use go get command to get the latest version of the gograph:

go get github.com/hmdsefi/gograph

Then you can use import the gograph to your code:

package main

import "github.com/hmdsefi/gograph"

How to Use

Graph

gograph contains the Graph[T comparable] interface that provides all needed APIs to manage a graph. All the supported graph types in gograph library implemented this interface.

type Graph[T comparable] interface {
GraphType

AddEdge(from, to *Vertex[T], options ...EdgeOptionFunc) (*Edge[T], error)
GetAllEdges(from, to *Vertex[T]) []*Edge[T]
GetEdge(from, to *Vertex[T]) *Edge[T]
EdgesOf(v *Vertex[T]) []*Edge[T]
RemoveEdges(edges ...*Edge[T])
AddVertexByLabel(label T, options ...VertexOptionFunc) *Vertex[T]
AddVertex(v *Vertex[T])
GetVertexByID(label T) *Vertex[T]
GetAllVerticesByID(label ...T) []*Vertex[T]
GetAllVertices() []*Vertex[T]
RemoveVertices(vertices ...*Vertex[T])
ContainsEdge(from, to *Vertex[T]) bool
ContainsVertex(v *Vertex[T]) bool
}

The generic type of the T in Graph interface represents the vertex label. The type of T should be comparable. You cannot use slices and function types for T.

Directed

graph := New[int](gograph.Directed())

graph.AddEdge(gograph.NewVertex(1), gograph.NewVertex(2))
graph.AddEdge(gograph.NewVertex(1), gograph.NewVertex(3))
graph.AddEdge(gograph.NewVertex(2), gograph.NewVertex(2))
graph.AddEdge(gograph.NewVertex(3), gograph.NewVertex(4))
graph.AddEdge(gograph.NewVertex(4), gograph.NewVertex(5))
graph.AddEdge(gograph.NewVertex(5), gograph.NewVertex(6))

Acyclic

graph := New[int](gograph.Directed())

graph.AddEdge(gograph.NewVertex(1), gograph.NewVertex(2))
graph.AddEdge(gograph.NewVertex(2), gograph.NewVertex(3))
_, err := graph.AddEdge(gograph.NewVertex(3), gograph.NewVertex(1))
if err != nil {
// do something
}

Undirected

// by default graph is undirected
graph := New[string]()

graph.AddEdge(gograph.NewVertex("A"), gograph.NewVertex("B"))
graph.AddEdge(gograph.NewVertex("A"), gograph.NewVertex("D"))
graph.AddEdge(gograph.NewVertex("B"), gograph.NewVertex("C"))
graph.AddEdge(gograph.NewVertex("B"), gograph.NewVertex("D"))

Weighted

graph := New[string]()

vA := gograph.AddVertexByLabel("A")
vB := gograph.AddVertexByLabel("B")
vC := gograph.AddVertexByLabel("C")
vD := gograph.AddVertexByLabel("D")

graph.AddEdge(vA, vB, gograph.WithEdgeWeight(4))
graph.AddEdge(vA, vD, gograph.WithEdgeWeight(3))
graph.AddEdge(vB, vC, gograph.WithEdgeWeight(3))
graph.AddEdge(vB, vD, gograph.WithEdgeWeight(1))
graph.AddEdge(vC, vD, gograph.WithEdgeWeight(2))

graph := New[string]()
vA := gograph.AddVertexByLabel("A", gograph.WithVertexWeight(3))
vB := gograph.AddVertexByLabel("B", gograph.WithVertexWeight(2))
vC := gograph.AddVertexByLabel("C", gograph.WithVertexWeight(4))

graph.AddEdge(vA, vB)
graph.AddEdge(vB, vC)

Traverse

Traverse package provides the iterator interface that guarantees all the algorithm export the same APIs:

type Iterator[T comparable] interface {
	HasNext() bool
	Next() *gograph.Vertex[T]
	Iterate(func(v *gograph.Vertex[T]) error) error
	Reset()
}

This package contains the following iterators:

• Breadth-First iterator
• Depth-First iterator
• Topological iterator
• Closest-First iterator
• Random Walk iterator

License

Apache License, please see LICENSE for details.