0.1.0 • Published 1 year ago
eugenics v0.1.0
Eugenics
Eugenics is an immutable typescript library for genetic algorithms. It is designed to be used in a functional programming style, returning new objects instead of mutating existing ones for libraries like React or Redux.
The library has been inspired by Python's DEAP library.
Installation
npm install eugenics
Usage
Knapsack problem
Here's an example implementation of the knapsack problem using eugenics
.
import { crossTwoPoint, mutFlipBit, selTournament, evolveSimple } from 'eugenics';
const generateProblem = n => {
const weights = [];
const values = [];
for (let i = 0; i < n; i++) {
weights.push(Math.ceil(Math.random() * 10 + 5));
values.push(Math.ceil(Math.random() * 10 + 5));
}
return { weights, values };
};
const max_weight = 40;
const problem = generateProblem(10);
const fitness = (individual: boolean[]) => {
let weight = 0;
let value = 0;
for (let i = 0; i < individual.length; i++) {
if (individual[i]) {
weight += problem.weights[i];
value += problem.values[i];
}
}
if (weight > max_weight) {
return 0;
}
return value;
};
const population = Array.from({ length: 100 }, () =>
Array.from({ length: problem.weights.length }, () => Math.random() > 0.5)
);
const {population: newPopulation} = evolveSimple(population, {
fitness,
crossover: crossTwoPoint,
mutation: mutFlipBit(0.05),
selection: selTournament,
}, {
ngen: 100
});
0.1.0
1 year ago