import numpy as np import random import math import time from typing import Callable, List, Tuple import matplotlib.pyplot as plt class QuantumInspiredMultiObjectiveOptimizer: def __init__(self, objective_fns: List[Callable[[List[float]], float]], dimension: int, population_size: int = 100, iterations: int = 200, tunneling_prob: float = 0.2, entanglement_factor: float = 0.5, mutation_scale: float = 1.0, archive_size: int = 200): self.objective_fns = objective_fns self.dimension = dimension self.population_size = population_size self.iterations = iterations self.tunneling_prob = tunneling_prob self.entanglement_factor = entanglement_factor self.mutation_scale = mutation_scale self.archive_size = archive_size self.population = [self._random_solution() for _ in range(population_size)] self.pareto_front = [] self.archive = [] def _random_solution(self) -> List[float]: return [random.uniform(-10, 10) for _ in range(self.dimension)] def _tunnel(self, solution: List[float], scale: float) -> List[float]: return [x + np.random.normal(0, scale) * random.choice([-1, 1]) if random.random() < self.tunneling_prob else x for x in solution] def _entangle(self, solution1: List[float], solution2: List[float], factor: float) -> List[float]: return [(1 - factor) * x + factor * y for x, y in zip(solution1, solution2)] def _evaluate(self, solution: List[float]) -> List[float]: return [fn(solution) for fn in self.objective_fns] def _dominates(self, obj1: List[float], obj2: List[float]) -> bool: return all(o1 <= o2 for o1, o2 in zip(obj1, obj2)) and any(o1 < o2 for o1, o2 in zip(obj1, obj2)) def _pareto_selection(self, scored_population: List[Tuple[List[float], List[float]]]) -> List[Tuple[List[float], List[float]]]: pareto = [] for candidate in scored_population: if not any(self._dominates(other[1], candidate[1]) for other in scored_population if other != candidate): pareto.append(candidate) unique_pareto = [] seen = set() for sol, obj in pareto: key = tuple(round(x, 6) for x in sol) if key not in seen: unique_pareto.append((sol, obj)) seen.add(key) return unique_pareto def _update_archive(self, pareto: List[Tuple[List[float], List[float]]]): combined = self.archive + pareto combined = self._pareto_selection(combined) self.archive = sorted(combined, key=lambda x: tuple(x[1]))[:self.archive_size] def optimize(self) -> Tuple[List[Tuple[List[float], List[float]]], float]: start_time = time.time() for i in range(self.iterations): adaptive_tunnel = self.mutation_scale * (1 - i / self.iterations) adaptive_entangle = self.entanglement_factor * (1 - i / self.iterations) scored_population = [(sol, self._evaluate(sol)) for sol in self.population] pareto = self._pareto_selection(scored_population) self._update_archive(pareto) self.pareto_front = pareto new_population = [p[0] for p in pareto] while len(new_population) < self.population_size: parent1 = random.choice(pareto)[0] parent2 = random.choice(pareto)[0] if parent1 == parent2: parent2 = self._tunnel(parent2, adaptive_tunnel) child = self._entangle(parent1, parent2, adaptive_entangle) child = self._tunnel(child, adaptive_tunnel) new_population.append(child) self.population = new_population duration = time.time() - start_time return self.archive, duration def sphere(x: List[float]) -> float: return sum(xi ** 2 for xi in x) def rastrigin(x: List[float]) -> float: return 10 * len(x) + sum(xi ** 2 - 10 * math.cos(2 * math.pi * xi) for xi in x) if __name__ == '__main__': optimizer = QuantumInspiredMultiObjectiveOptimizer( objective_fns=[sphere, rastrigin], dimension=20, population_size=100, iterations=200, tunneling_prob=0.2, entanglement_factor=0.5, mutation_scale=1.0, archive_size=300 ) pareto_front, duration = optimizer.optimize() print(f"Optimization completed in {duration:.2f} seconds") print(f"Pareto front size: {len(pareto_front)}") for sol, scores in pareto_front: print("Solution:", sol, "Objectives:", scores) if len(pareto_front[0][1]) == 2: x_vals = [obj[0] for _, obj in pareto_front] y_vals = [obj[1] for _, obj in pareto_front] plt.scatter(x_vals, y_vals, c='blue', label='Pareto Front') plt.xlabel('Objective 1') plt.ylabel('Objective 2') plt.title('Pareto Front Visualization') plt.legend() plt.grid(True) plt.show()