Source code for mealpy.swarm_based.GTO

#!/usr/bin/env python
# Created by "Thieu" at 21:58, 16/03/2023 ----------%                                                                               
#       Email: nguyenthieu2102@gmail.com            %                                                    
#       Github: https://github.com/thieu1995        %                         
# --------------------------------------------------%

import numpy as np
from mealpy.optimizer import Optimizer


[docs]class OriginalGTO(Optimizer): """ The original version of: Giant Trevally Optimizer (GTO) Notes: 1. This version is implemented exactly as described in the paper. 2. https://www.mathworks.com/matlabcentral/fileexchange/121358-giant-trevally-optimizer-gto 3. https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9955508 Hyper-parameters should fine-tune in approximate range to get faster convergence toward the global optimum: + A (float): a position-change-controlling parameter with a range from 0.3 to 0.4, default=0.4 + H (float): initial value for specifies the jumping slope function, default=2.0 Examples ~~~~~~~~ >>> import numpy as np >>> from mealpy import FloatVar, GTO >>> >>> def objective_function(solution): >>> return np.sum(solution**2) >>> >>> problem_dict = { >>> "bounds": FloatVar(n_vars=30, lb=(-10.,) * 30, ub=(10.,) * 30, name="delta"), >>> "minmax": "min", >>> "obj_func": objective_function >>> } >>> >>> model = GTO.OriginalGTO(epoch=1000, pop_size=50) >>> g_best = model.solve(problem_dict) >>> print(f"Solution: {g_best.solution}, Fitness: {g_best.target.fitness}") >>> print(f"Solution: {model.g_best.solution}, Fitness: {model.g_best.target.fitness}") References ~~~~~~~~~~ [1] Sadeeq, H. T., & Abdulazeez, A. M. (2022). Giant Trevally Optimizer (GTO): A Novel Metaheuristic Algorithm for Global Optimization and Challenging Engineering Problems. IEEE Access, 10, 121615-121640. """ def __init__(self, epoch: int = 10000, pop_size: int = 100, A: float = 0.4, H: float = 2.0, **kwargs: object) -> None: """ Args: epoch (int): maximum number of iterations, default = 10000 pop_size (int): number of population size, default = 100 A (float): a position-change-controlling parameter with a range from 0.3 to 0.4, default=0.4 H (float): initial value for specifies the jumping slope function, default=2.0 """ super().__init__(**kwargs) self.epoch = self.validator.check_int("epoch", epoch, [1, 100000]) self.pop_size = self.validator.check_int("pop_size", pop_size, [5, 10000]) self.A = self.validator.check_float("A", A, [-10., 10.]) self.H = self.validator.check_float("H", H, [1., 10.]) self.set_parameters(["epoch", "pop_size", "A", "H"]) self.sort_flag = True
[docs] def evolve(self, epoch): """ The main operations (equations) of algorithm. Inherit from Optimizer class Args: epoch (int): The current iteration """ # Step 1: Extensive Search pop_new = [] for idx in range(0, self.pop_size): # Eq.(4) pos_new = self.g_best.solution * self.generator.random() + ((self.problem.ub - self.problem.lb) * self.generator.random() + self.problem.lb) * \ self.get_levy_flight_step(beta=1.5, multiplier=0.01, size=self.problem.n_dims, case=-1) pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax) self.pop, self.g_best = self.update_global_best_agent(self.pop, save=False) # Step 2: Choosing Area pos_list = np.array([agent.solution for agent in self.pop]) pos_m = np.mean(pos_list, axis=0) pop_new = [] for idx in range(0, self.pop_size): r3 = self.generator.random() pos_new = self.g_best.solution * self.A * r3 + pos_m - self.pop[idx].solution * r3 # Eq. 7 pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax) _, self.g_best = self.update_global_best_agent(self.pop, save=False) # Step 3: Attacking H = self.generator.random() * (self.H - (epoch+1) * self.H / self.epoch) # Eq.(15) pop_new = [] for idx in range(0, self.pop_size): # the distance between the prey and the attacker, and can be calculated using (12): dist = np.sum(np.abs(self.g_best.solution - self.pop[idx].solution)) theta2 = (360 - 0) * self.generator.random() + 0 theta1 = (1.33 / 1.00029) * np.sin(np.radians(theta2)) # calculate theta_1 using (10) VD = np.sin(np.radians(theta1)) * dist # Eq. 11 # Eq. (13) pos_new = self.pop[idx].solution * np.sin(np.radians(theta2)) * self.pop[idx].target.fitness + VD + H pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax)
[docs]class Matlab102GTO(Optimizer): """ The conversion of Matlab code (version 1.0.2 - 27/04/2023) to Python code of: Giant Trevally Optimizer (GTO) Links: 1. https://www.mathworks.com/matlabcentral/fileexchange/121358-giant-trevally-optimizer-gto 2. https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9955508 Notes: 1. The authors sent me an email asking to update the algorithm. In this version, they removed 2 for loops in the epoch (generations) based on my comments, so the computation time will reduce to 3*pop_size from 2*pop_size^2 + pop_size. However, this will also lead to a reduction in performance results. My question: Are the results in the paper valid? 2. I have decided to implement the original version of the algorithm exactly as described in the paper (OriginalGTO). Examples ~~~~~~~~ >>> import numpy as np >>> from mealpy import FloatVar, GTO >>> >>> def objective_function(solution): >>> return np.sum(solution**2) >>> >>> problem_dict = { >>> "bounds": FloatVar(n_vars=30, lb=(-10.,) * 30, ub=(10.,) * 30, name="delta"), >>> "minmax": "min", >>> "obj_func": objective_function >>> } >>> >>> model = GTO.Matlab102GTO(epoch=1000, pop_size=50) >>> g_best = model.solve(problem_dict) >>> print(f"Solution: {g_best.solution}, Fitness: {g_best.target.fitness}") >>> print(f"Solution: {model.g_best.solution}, Fitness: {model.g_best.target.fitness}") References ~~~~~~~~~~ [1] Sadeeq, H. T., & Abdulazeez, A. M. (2022). Giant Trevally Optimizer (GTO): A Novel Metaheuristic Algorithm for Global Optimization and Challenging Engineering Problems. IEEE Access, 10, 121615-121640. """ def __init__(self, epoch: int = 10000, pop_size: int = 100, **kwargs: object) -> None: """ Args: epoch (int): maximum number of iterations, default = 10000 pop_size (int): number of population size, default = 100 """ super().__init__(**kwargs) self.epoch = self.validator.check_int("epoch", epoch, [1, 100000]) self.pop_size = self.validator.check_int("pop_size", pop_size, [5, 10000]) self.set_parameters(["epoch", "pop_size"]) self.sort_flag = True
[docs] def evolve(self, epoch): """ The main operations (equations) of algorithm. Inherit from Optimizer class Args: epoch (int): The current iteration """ # Step 1: Extensive Search pop_new = [] for idx in range(0, self.pop_size): # foraging movement patterns of giant trevallies are simulated using Eq.(4) pos_new = self.g_best.solution * self.generator.random() + ((self.problem.ub - self.problem.lb) * self.generator.random() + self.problem.lb) * \ self.get_levy_flight_step(beta=1.5, multiplier=0.01, size=self.problem.n_dims, case=-1) pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax) self.pop, self.g_best = self.update_global_best_agent(self.pop, save=False) # Step 2: Choosing Area A = 0.4 pop_new = [] for idx in range(0, self.pop_size): pos_m = np.mean(np.array([agent.solution for agent in self.pop]), axis=0) # In the choosing area step, giant trevallies identify and select the best area in terms of # the amount of food (seabirds) within the selected search space where they can hunt for prey. r3 = self.generator.random() pos_new = self.g_best.solution * A * r3 + pos_m - self.pop[idx].solution * r3 # Eq. 7 pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax) self.pop, self.g_best = self.update_global_best_agent(self.pop, save=False) # Step 3: Attacking H = self.generator.random() * (2.0 - (epoch+1) * 2.0 / self.epoch) # Eq.(15) pop_new = [] for idx in range(0, self.pop_size): # the distance between the prey and the attacker, and can be calculated using (12): dist = np.sum(np.abs(self.g_best.solution - self.pop[idx].solution)) theta2 = (360 - 0) * self.generator.random() + 0 theta1 = 1.3296 * np.sin(np.radians(theta2)) # calculate theta_1 using (10) # visual distortion indicates the apparent height of the bird, which is always seen # to be higher than its actual height due to the refraction of the light. VD = np.sin(np.radians(theta1)) * dist # Eq. 11 # the behavior of giant trevally when chasing and jumping out of the water is mathematically simulated using (13) pos_new = self.pop[idx].solution * np.sin(np.radians(theta2)) * self.pop[idx].target.fitness + VD + H pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax)
[docs]class Matlab101GTO(Optimizer): """ The conversion of Matlab code (version 1.0.1 - 29/11/2022) to Python code of: Giant Trevally Optimizer (GTO) Links: 1. https://www.mathworks.com/matlabcentral/fileexchange/121358-giant-trevally-optimizer-gto 2. https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9955508 Notes: 1. This algorithm costs a huge amount of computational resources in each epoch. Therefore, be careful when using the maximum number of generations as a stopping condition. 2. Other algorithms update around K*pop_size times in each epoch, this algorithm updates around 2*pop_size^2 + pop_size times 3. This version is used by the authors to compared with other algorithms in their paper. Examples ~~~~~~~~ >>> import numpy as np >>> from mealpy import FloatVar, GTO >>> >>> def objective_function(solution): >>> return np.sum(solution**2) >>> >>> problem_dict = { >>> "bounds": FloatVar(n_vars=30, lb=(-10.,) * 30, ub=(10.,) * 30, name="delta"), >>> "minmax": "min", >>> "obj_func": objective_function >>> } >>> >>> model = GTO.Matlab101GTO(epoch=1000, pop_size=50) >>> g_best = model.solve(problem_dict) >>> print(f"Solution: {g_best.solution}, Fitness: {g_best.target.fitness}") >>> print(f"Solution: {model.g_best.solution}, Fitness: {model.g_best.target.fitness}") References ~~~~~~~~~~ [1] Sadeeq, H. T., & Abdulazeez, A. M. (2022). Giant Trevally Optimizer (GTO): A Novel Metaheuristic Algorithm for Global Optimization and Challenging Engineering Problems. IEEE Access, 10, 121615-121640. """ def __init__(self, epoch: int = 10000, pop_size: int = 100, **kwargs: object) -> None: """ Args: epoch (int): maximum number of iterations, default = 10000 pop_size (int): number of population size, default = 100 """ super().__init__(**kwargs) self.epoch = self.validator.check_int("epoch", epoch, [1, 100000]) self.pop_size = self.validator.check_int("pop_size", pop_size, [5, 10000]) self.set_parameters(["epoch", "pop_size"]) self.sort_flag = True
[docs] def evolve(self, epoch): """ The main operations (equations) of algorithm. Inherit from Optimizer class Args: epoch (int): The current iteration """ # Step 1: Extensive Search for idx in range(0, self.pop_size): pop_new = [] for jdx in range(0, self.pop_size): if idx == jdx: continue # foraging movement patterns of giant trevallies are simulated using Eq.(4) pos_new = self.g_best.solution * self.generator.random() + ((self.problem.ub - self.problem.lb) * self.generator.random() + self.problem.lb) * self.get_levy_flight_step(beta=1.5, multiplier=0.01, size=self.problem.n_dims, case=-1) pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: pop_new[-1].target = self.get_target(pos_new) pop_new = self.update_target_for_population(pop_new) self.pop[idx] = self.get_best_agent(pop_new + [self.pop[idx]], self.problem.minmax) _, self.g_best = self.update_global_best_agent(self.pop, save=False) # Step 2: Choosing Area pos_list = np.array([agent.solution for agent in self.pop]) pos_m = np.mean(pos_list, axis=0) A = 0.4 pop_new = [] for idx in range(0, self.pop_size): # In the choosing area step, giant trevallies identify and select the best area in terms of # the amount of food (seabirds) within the selected search space where they can hunt for prey. r3 = self.generator.random() pos_new = self.g_best.solution * A * r3 + pos_m - self.pop[idx].solution * r3 # Eq. 7 pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: agent.target = self.get_target(pos_new) self.pop[idx] = self.get_better_agent(agent, self.pop[idx], self.problem.minmax) if self.mode in self.AVAILABLE_MODES: pop_new = self.update_target_for_population(pop_new) self.pop = self.greedy_selection_population(self.pop, pop_new, self.problem.minmax) _, self.g_best = self.update_global_best_agent(self.pop, save=False) # Step 3: Attacking H = self.generator.random() * (2.0 - epoch * 2.0 / self.epoch) # Eq.(15) for idx in range(0, self.pop_size): pop_new = [] for jdx in range(0, self.pop_size): if idx == jdx: continue # the distance between the prey and the attacker, and can be calculated using (12): dist = np.sum(np.abs(self.g_best.solution - self.pop[idx].solution)) theta2 = (360 - 0) * self.generator.random() + 0 theta1 = 1.3296 * np.sin(np.radians(theta2)) # calculate theta_1 using (10) # visual distortion indicates the apparent height of the bird, which is always seen # to be higher than its actual height due to the refraction of the light. VD = np.sin(np.radians(theta1)) * dist # Eq. 11 # the behavior of giant trevally when chasing and jumping out of the water is mathematically simulated using (13) pos_new = self.pop[idx].solution * np.sin(np.radians(theta2)) * self.pop[idx].target.fitness + VD + H pos_new = self.correct_solution(pos_new) agent = self.generate_empty_agent(pos_new) pop_new.append(agent) if self.mode not in self.AVAILABLE_MODES: pop_new[-1].target = self.get_target(pos_new) pop_new = self.update_target_for_population(pop_new) self.pop[idx] = self.get_best_agent(pop_new + [self.pop[idx]], self.problem.minmax)