Ant Colony Optimization

November 16, 2016

Since I created ant colony optimization algorithm this time, I will introduce it.

Here is my program, please refer this if you want.

Ant Colony Optimization (GitHub)

What is ant colony optimization?

Ant colony optimization is a probabilistic solution to solve like the shortest path problem,

imitates the ant behavior in finding a route to food.

Please see here for details of the algorithm.

Ant Colony Optimization

Program description

In this program, we can find an approximate solution of the shortest path problem as follows.


  • Start from s and go through all nodes
  • The number on the path represents the distance between the nodes

In this example, when passing in the order of a, d, b, c, the distance becomes the shortest 8.1.


How to use this

Usage is as follows.

const AntColony = require("./ant-colony")
const NOA = 10
const LIMIT = 100
const Q = 3
const RHO = 0.8
const EPSILON = 0.15
const distance = [
  //  s    a    b    c    d
  [0.0, 4.0, 4.0, 4.7, 5.0], // start
  [0.0, 0.0, 1.2, 2.5, 1.7], // a
  [0.0, 1.2, 0.0, 1.0, 1.4], // b
  [0.0, 2.5, 1.0, 0.0, 2.0], // c
  [0.0, 1.7, 1.4, 2.0, 0.0], // d
const ac = new AntColony(NOA, LIMIT, Q, RHO, EPSILON, distance)

Variable Meaning
NOA Number of ants
LIMIT Maximum number of attempts
Q Influence of pheromone
RHO Evaporation rate of pheromone
EPSILON The probability of not considering the pheromone concentration when an ant chooses the next node (epsilon-greedy method)
distance Two-dimensional array of graph

© 2021, Yosuke Saito