diff --git a/src/niapy/algorithms/other/aso.py b/src/niapy/algorithms/other/aso.py index 882e6cb44..b72477cfe 100644 --- a/src/niapy/algorithms/other/aso.py +++ b/src/niapy/algorithms/other/aso.py @@ -1,183 +1,196 @@ # encoding=utf8 -import logging +"""Anarchic Society Optimization algorithm.""" import numpy as np +from scipy.spatial.distance import euclidean from niapy.algorithms.algorithm import Algorithm -from niapy.util import full_array, euclidean +from niapy.util.array import full_array -logging.basicConfig() -logger = logging.getLogger('niapy.algorithms.other') -logger.setLevel('INFO') +__all__ = [ + 'AnarchicSocietyOptimization', + 'elitism', + 'sequential', + 'crossover', +] -__all__ = ['AnarchicSocietyOptimization', 'elitism', 'sequential', 'crossover'] - -def elitism(x, xpb, xb, xr, mp_c, mp_s, mp_p, mutation_rate, crossover_probability, task, rng): - r"""Select the best of all three strategies. +def _mp_c(x, f, cr, mp, rng): + r"""Get new position based on fickleness (Fickleness Index strategy). Args: - x (numpy.ndarray): individual position. - xpb (numpy.ndarray): individuals best position. - xb (numpy.ndarray): current best position. - xr (numpy.ndarray): random individual. - mp_c (float): Fickleness index value. - mp_s (float): External irregularity index value. - mp_p (float): Internal irregularity index value. - mutation_rate (float): scale factor. - crossover_probability (float): crossover factor. - task (Task): optimization task. - rng (numpy.random.Generator): random number generator. + x (numpy.ndarray): Current individual's position. + f (float): Scale factor. + cr (float): Crossover probability. + mp (float): Fickleness index value. + rng (numpy.random.Generator): Random number generator. Returns: - Tuple[numpy.ndarray, float]: - 1. New position of individual - 2. New positions fitness/function value - + numpy.ndarray: New position. """ - xn = [task.repair(mp_current(x, mutation_rate, crossover_probability, mp_c, rng), rng=rng), - task.repair(mp_society(x, xr, xb, crossover_probability, mp_s, rng), rng=rng), - task.repair(mp_past(x, xpb, crossover_probability, mp_p, rng), rng=rng)] - xn_f = np.apply_along_axis(task.eval, 1, xn) - ib = np.argmin(xn_f) - return xn[ib], xn_f[ib] + xn = x.copy() + if mp < 0.5: + b = np.sort(rng.choice(len(x), 2, replace=False)) + xn[b[0]:b[1]] = xn[b[0]:b[1]] + f * rng.standard_normal(b[1] - b[0]) + else: + mask = rng.random(len(x)) < cr + xn[mask] = xn[mask] + f * rng.standard_normal(np.sum(mask)) + return xn -def sequential(x, xpb, xb, xr, mp_c, mp_s, mp_p, mutation_rate, crossover_probability, task, rng): - r"""Sequentially combines all three strategies. +def _mp_s(x, xr, xb, cr, mp, rng): + r"""Get new position based on external irregularity (External Irregularity Index strategy). Args: - x (numpy.ndarray): individual position. - xpb (numpy.ndarray): individuals best position. - xb (numpy.ndarray): current best position. - xr (numpy.ndarray): random individual. - mp_c (float): Fickleness index value. - mp_s (float): External irregularity index value. - mp_p (float): Internal irregularity index value. - mutation_rate (float): scale factor. - crossover_probability (float): crossover factor. - task (Task): optimization task. - rng (numpy.random.Generator): random number generator. + x (numpy.ndarray): Current individual's position. + xr (numpy.ndarray): Random individual's position. + xb (numpy.ndarray): Global best individual's position. + cr (float): Crossover probability. + mp (float): External irregularity index value. + rng (numpy.random.Generator): Random number generator. Returns: - tuple[numpy.ndarray, float]: - 1. new position - 2. new positions function/fitness value - + numpy.ndarray: New position. """ - xn = task.repair(mp_society( - mp_past(mp_current(x, mutation_rate, crossover_probability, mp_c, rng), xpb, crossover_probability, mp_p, rng), - xr, - xb, crossover_probability, mp_s, rng), rng=rng) - return xn, task.eval(xn) + xn = x.copy() + if mp < 0.25: + b = np.sort(rng.choice(len(x), 2, replace=False)) + xn[b[0]:b[1]] = xb[b[0]:b[1]] + elif mp < 0.5: + mask = rng.random(len(x)) < cr + xn[mask] = xb[mask] + elif mp < 0.75: + b = np.sort(rng.choice(len(x), 2, replace=False)) + xn[b[0]:b[1]] = xr[b[0]:b[1]] + else: + mask = rng.random(len(x)) < cr + xn[mask] = xr[mask] + return xn -def crossover(x, xpb, xb, xr, mp_c, mp_s, mp_p, mutation_rate, crossover_probability, task, rng): - r"""Create a crossover over all three strategies. +def _mp_p(x, xpb, cr, mp, rng): + r"""Get new position based on internal irregularity (Internal Irregularity Index strategy). Args: - x (numpy.ndarray): individual position. - xpb (numpy.ndarray): individuals best position. - xb (numpy.ndarray): current best position. - xr (numpy.ndarray): random individual. - mp_c (float): Fickleness index value. - mp_s (float): External irregularity index value. - mp_p (float): Internal irregularity index value. - mutation_rate (float): scale factor. - crossover_probability (float): crossover factor. - task (Task): optimization task. - rng (numpy.random.Generator): random number generator. + x (numpy.ndarray): Current individual's position. + xpb (numpy.ndarray): Individual's personal best position. + cr (float): Crossover probability. + mp (float): Internal irregularity index value. + rng (numpy.random.Generator): Random number generator. Returns: - Tuple[numpy.ndarray, float]: - 1. new position - 2. new positions function/fitness value. - + numpy.ndarray: New position. """ - xns = [task.repair(mp_current(x, mutation_rate, crossover_probability, mp_c, rng), rng=rng), - task.repair(mp_society(x, xr, xb, crossover_probability, mp_s, rng), rng=rng), - task.repair(mp_past(x, xpb, crossover_probability, mp_p, rng), rng=rng)] - index = rng.integers(len(xns)) - x = np.asarray([xns[index][i] if rng.random() < crossover_probability else x[i] for i in range(len(x))]) - return x, task.eval(x) + xn = x.copy() + if mp < 0.5: + b = np.sort(rng.choice(len(x), 2, replace=False)) + xn[b[0]:b[1]] = xpb[b[0]:b[1]] + else: + mask = rng.random(len(x)) < cr + xn[mask] = xpb[mask] + return xn -def mp_current(x, mutation_rate, crossover_rate, mp, rng): - r"""Get bew position based on fickleness. +def elitism(x, xpb, xb, xr, mp_c, mp_s, mp_p, f, cr, task, rng): + r"""Select the best of all three movement strategies. Args: - x (numpy.ndarray): Current individuals position. - mutation_rate (float): Scale factor. - crossover_rate (float): Crossover probability. - mp (float): Fickleness index value - rng (numpy.random.Generator): Random number generator + x (numpy.ndarray): Individual's current position. + xpb (numpy.ndarray): Individual's personal best position. + xb (numpy.ndarray): Global best position. + xr (numpy.ndarray): Random individual's position. + mp_c (float): Fickleness index value. + mp_s (float): External irregularity index value. + mp_p (float): Internal irregularity index value. + f (float): Scale factor. + cr (float): Crossover probability. + task (Task): Optimization task. + rng (numpy.random.Generator): Random number generator. Returns: - numpy.ndarray: New position - + Tuple[numpy.ndarray, float]: + 1. New position of individual. + 2. New position's fitness value. """ - if mp < 0.5: - b = np.sort(rng.choice(len(x), 2, replace=False)) - x[b[0]:b[1]] = x[b[0]:b[1]] + mutation_rate * rng.normal(0, 1, b[1] - b[0]) - return x - return np.asarray( - [x[i] + mutation_rate * rng.normal(0, 1) if rng.random() < crossover_rate else x[i] for i in range(len(x))]) + candidates = [ + task.repair(_mp_c(x, f, cr, mp_c, rng), rng=rng), + task.repair(_mp_s(x, xr, xb, cr, mp_s, rng), rng=rng), + task.repair(_mp_p(x, xpb, cr, mp_p, rng), rng=rng), + ] + fitnesses = np.apply_along_axis(task.eval, 1, candidates) + best_idx = np.argmin(fitnesses) + return candidates[best_idx], fitnesses[best_idx] -def mp_society(x, xr, xb, crossover_rate, mp, rng): - r"""Get new position based on external irregularity. +def sequential(x, xpb, xb, xr, mp_c, mp_s, mp_p, f, cr, task, rng): + r"""Sequentially apply all three movement strategies. Args: - x (numpy.ndarray): Current individuals position. - xr (numpy.ndarray): Random individuals position. - xb (numpy.ndarray): Global best individuals position. - crossover_rate (float): Crossover probability. - mp (float): External irregularity index. + x (numpy.ndarray): Individual's current position. + xpb (numpy.ndarray): Individual's personal best position. + xb (numpy.ndarray): Global best position. + xr (numpy.ndarray): Random individual's position. + mp_c (float): Fickleness index value. + mp_s (float): External irregularity index value. + mp_p (float): Internal irregularity index value. + f (float): Scale factor. + cr (float): Crossover probability. + task (Task): Optimization task. rng (numpy.random.Generator): Random number generator. Returns: - numpy.ndarray: New position. - + Tuple[numpy.ndarray, float]: + 1. New position. + 2. New position's fitness value. """ - if mp < 0.25: - b = np.sort(rng.choice(len(x), 2, replace=False)) - x[b[0]:b[1]] = xb[b[0]:b[1]] - return x - elif mp < 0.5: - return np.asarray([xb[i] if rng.random() < crossover_rate else x[i] for i in range(len(x))]) - elif mp < 0.75: - b = np.sort(rng.choice(len(x), 2, replace=False)) - x[b[0]:b[1]] = xr[b[0]:b[1]] - return x - return np.asarray([xr[i] if rng.random() < crossover_rate else x[i] for i in range(len(x))]) + xn = task.repair( + _mp_s( + _mp_p(_mp_c(x, f, cr, mp_c, rng), xpb, cr, mp_p, rng), + xr, xb, cr, mp_s, rng, + ), + rng=rng, + ) + return xn, task.eval(xn) -def mp_past(x, xpb, crossover_rate, mp, rng): - r"""Get new position based on internal irregularity. +def crossover(x, xpb, xb, xr, mp_c, mp_s, mp_p, f, cr, task, rng): + r"""Create a crossover over all three movement strategies. Args: - x (numpy.ndarray): Current individuals position. - xpb (numpy.ndarray): Current individuals personal best position. - crossover_rate (float): Crossover probability. - mp (float): Internal irregularity index value. + x (numpy.ndarray): Individual's current position. + xpb (numpy.ndarray): Individual's personal best position. + xb (numpy.ndarray): Global best position. + xr (numpy.ndarray): Random individual's position. + mp_c (float): Fickleness index value. + mp_s (float): External irregularity index value. + mp_p (float): Internal irregularity index value. + f (float): Scale factor. + cr (float): Crossover probability. + task (Task): Optimization task. rng (numpy.random.Generator): Random number generator. Returns: - numpy.ndarray: Current individuals new position. - + Tuple[numpy.ndarray, float]: + 1. New position. + 2. New position's fitness value. """ - if mp < 0.5: - b = np.sort(rng.choice(len(x), 2, replace=False)) - x[b[0]:b[1]] = xpb[b[0]:b[1]] - return x - return np.asarray([xpb[i] if rng.random() < crossover_rate else x[i] for i in range(len(x))]) + candidates = [ + task.repair(_mp_c(x, f, cr, mp_c, rng), rng=rng), + task.repair(_mp_s(x, xr, xb, cr, mp_s, rng), rng=rng), + task.repair(_mp_p(x, xpb, cr, mp_p, rng), rng=rng), + ] + xn = np.array([ + candidates[rng.integers(len(candidates))][i] if rng.random() < cr else x[i] + for i in range(len(x)) + ]) + return xn, task.eval(xn) class AnarchicSocietyOptimization(Algorithm): r"""Implementation of Anarchic Society Optimization algorithm. Algorithm: - Anarchic Society Optimization algorithm + Anarchic Society Optimization Date: 2018 @@ -189,94 +202,99 @@ class AnarchicSocietyOptimization(Algorithm): MIT Reference paper: - Ahmadi-Javid, Amir. "Anarchic Society Optimization: A human-inspired method." Evolutionary Computation (CEC), 2011 IEEE Congress on. IEEE, 2011. + Ahmadi-Javid, Amir. "Anarchic Society Optimization: A human-inspired method." + Evolutionary Computation (CEC), 2011 IEEE Congress on. IEEE, 2011. Attributes: - Name (list of str): List of stings representing name of algorithm. + Name (List[str]): List of strings representing algorithm names. alpha (List[float]): Factor for fickleness index function :math:`\in [0, 1]`. gamma (List[float]): Factor for external irregularity index function :math:`\in [0, \infty)`. theta (List[float]): Factor for internal irregularity index function :math:`\in [0, \infty)`. - d (Callable[[float, float], float]): function that takes two arguments that are function values and calculates the distance between them. - dn (Callable[[numpy.ndarray, numpy.ndarray], float]): function that takes two arguments that are points in function landscape and calculates the distance between them. - nl (float): Normalized range for neighborhood search :math:`\in (0, 1]`. - F (float): Mutation parameter. - CR (float): Crossover parameter :math:`\in [0, 1]`. - Combination (Callable[numpy.ndarray, numpy.ndarray, numpy.ndarray, numpy.ndarray, float, float, float, float, float, float, Task, numpy.random.Generator]): Function for combining individuals to get new position/individual. + d (Callable): Distance function for fitness values. + dn (Callable): Distance function for positions in search space. + nl (float): Normalized neighbourhood range :math:`\in (0, 1]`. + f (float): Mutation scale factor. + cr (float): Crossover probability :math:`\in [0, 1]`. + combination (Callable): Strategy for combining movement operators. See Also: * :class:`niapy.algorithms.Algorithm` + Examples: + >>> from niapy.algorithms.other import AnarchicSocietyOptimization + >>> from niapy.task import Task + >>> from niapy.benchmarks import Sphere + >>> task = Task(problem=Sphere(dimension=10), max_evals=10000) + >>> algo = AnarchicSocietyOptimization(population_size=43) + >>> best, best_fit = algo.run(task) + >>> print(best_fit) """ Name = ['AnarchicSocietyOptimization', 'ASO'] + def __init__(self, population_size=43, alpha=(1, 0.83), gamma=(1.17, 0.56), + theta=(0.932, 0.832), d=euclidean, dn=euclidean, nl=1.0, + f=1.2, cr=0.25, combination=elitism, *args, **kwargs): + r"""Initialize AnarchicSocietyOptimization algorithm.""" + super().__init__(population_size=population_size, *args, **kwargs) + self.set_parameters(population_size=population_size, alpha=alpha, gamma=gamma, + theta=theta, d=d, dn=dn, nl=nl, f=f, cr=cr, + combination=combination) + @staticmethod def info(): r"""Get basic information about the algorithm. Returns: str: Basic information. - - See Also: - :func:`niapy.algorithms.algorithm.Algorithm.info` - """ - return r"""Ahmadi-Javid, Amir. "Anarchic Society Optimization: A human-inspired method." Evolutionary Computation (CEC), 2011 IEEE Congress on. IEEE, 2011.""" - - def __init__(self, population_size=43, alpha=(1, 0.83), gamma=(1.17, 0.56), theta=(0.932, 0.832), d=euclidean, - dn=euclidean, nl=1, mutation_rate=1.2, crossover_rate=0.25, combination=elitism, *args, **kwargs): - r"""Initialize AnarchicSocietyOptimization. - - Args: - population_size (Optional[int]): Population size. - alpha (Optional[Tuple[float, ...]]): Factor for fickleness index function :math:`\in [0, 1]`. - gamma (Optional[Tuple[float, ...]]): Factor for external irregularity index function :math:`\in [0, \infty)`. - theta (Optional[List[float]]): Factor for internal irregularity index function :math:`\in [0, \infty)`. - d (Optional[Callable[[float, float], float]]): function that takes two arguments that are function values and calculates the distance between them. - dn (Optional[Callable[[numpy.ndarray, numpy.ndarray], float]]): function that takes two arguments that are points in function landscape and calculates the distance between them. - nl (Optional[float]): Normalized range for neighborhood search :math:`\in (0, 1]`. - mutation_rate (Optional[float]): Mutation parameter. - crossover_rate (Optional[float]): Crossover parameter :math:`\in [0, 1]`. - combination (Optional[Callable[numpy.ndarray, numpy.ndarray, numpy.ndarray, numpy.ndarray, float, float, float, float, float, float, Task, numpy.random.Generator]]): Function for combining individuals to get new position/individual. + return r"""Ahmadi-Javid, Amir. "Anarchic Society Optimization: A human-inspired method." + Evolutionary Computation (CEC), 2011 IEEE Congress on. IEEE, 2011.""" - See Also: - * :func:`niapy.algorithms.Algorithm.set_parameters` + @staticmethod + def type_parameters(): + r"""Get functions for checking parameter values. + Returns: + Dict[str, Callable]: + * alpha: Check alpha parameter. + * gamma: Check gamma parameter. + * theta: Check theta parameter. + * nl: Check neighbourhood range. + * f: Check scale factor. + * cr: Check crossover probability. """ - super().__init__(population_size, *args, **kwargs) - self.alpha = alpha - self.gamma = gamma - self.theta = theta - self.d = d - self.dn = dn - self.nl = nl - self.mutation_rate = mutation_rate - self.crossover_rate = crossover_rate - self.combination = combination + d = Algorithm.type_parameters() + d.update({ + 'alpha': lambda x: True, + 'gamma': lambda x: True, + 'theta': lambda x: True, + 'nl': lambda x: isinstance(x, float) and 0 < x <= 1, + 'f': lambda x: isinstance(x, (int, float)) and x > 0, + 'cr': lambda x: isinstance(x, float) and 0 <= x <= 1, + }) + return d - def set_parameters(self, population_size=43, alpha=(1, 0.83), gamma=(1.17, 0.56), theta=(0.932, 0.832), d=euclidean, - dn=euclidean, nl=1, mutation_rate=1.2, crossover_rate=0.25, combination=elitism, **kwargs): - r"""Set the parameters for the algorithm. + def set_parameters(self, population_size=43, alpha=(1, 0.83), gamma=(1.17, 0.56), + theta=(0.932, 0.832), d=euclidean, dn=euclidean, nl=1.0, + f=1.2, cr=0.25, combination=elitism, **kwargs): + r"""Set algorithm parameters. Args: - population_size (Optional[int]): Population size. - alpha (Optional[Tuple[float, ...]]): Factor for fickleness index function :math:`\in [0, 1]`. - gamma (Optional[Tuple[float, ...]]): Factor for external irregularity index function :math:`\in [0, \infty)`. - theta (Optional[List[float]]): Factor for internal irregularity index function :math:`\in [0, \infty)`. - d (Optional[Callable[[float, float], float]]): function that takes two arguments that are function values and calculates the distance between them. - dn (Optional[Callable[[numpy.ndarray, numpy.ndarray], float]]): function that takes two arguments that are points in function landscape and calculates the distance between them. - nl (Optional[float]): Normalized range for neighborhood search :math:`\in (0, 1]`. - mutation_rate (Optional[float]): Mutation parameter. - crossover_rate (Optional[float]): Crossover parameter :math:`\in [0, 1]`. - combination (Optional[Callable[numpy.ndarray, numpy.ndarray, numpy.ndarray, numpy.ndarray, float, float, float, float, float, float, Task, numpy.random.Generator]]): Function for combining individuals to get new position/individual. + population_size (Optional[int]): Number of individuals in population. + alpha (Optional[List[float]]): Factors for fickleness index :math:`\in [0, 1]`. + gamma (Optional[List[float]]): Factors for external irregularity index :math:`\in [0, \infty)`. + theta (Optional[List[float]]): Factors for internal irregularity index :math:`\in [0, \infty)`. + d (Optional[Callable]): Distance function for fitness values. + dn (Optional[Callable]): Distance function for positions. + nl (Optional[float]): Normalized neighbourhood range :math:`\in (0, 1]`. + f (Optional[float]): Mutation scale factor. + cr (Optional[float]): Crossover probability :math:`\in [0, 1]`. + combination (Optional[Callable]): Movement strategy combination function. + Choose from :func:`elitism`, :func:`sequential`, :func:`crossover`. See Also: * :func:`niapy.algorithms.Algorithm.set_parameters` - * Combination methods: - * :func:`niapy.algorithms.other.elitism` - * :func:`niapy.algorithms.other.crossover` - * :func:`niapy.algorithms.other.sequential` - """ super().set_parameters(population_size=population_size, **kwargs) self.alpha = alpha @@ -285,215 +303,249 @@ def set_parameters(self, population_size=43, alpha=(1, 0.83), gamma=(1.17, 0.56) self.d = d self.dn = dn self.nl = nl - self.mutation_rate = mutation_rate - self.crossover_rate = crossover_rate + self.f = f + self.cr = cr self.combination = combination def get_parameters(self): - r"""Get parameters of the algorithm. + r"""Get parameter values of the algorithm. Returns: - Dict[str, Any]: Algorithm parameters. - + Dict[str, Any]: Parameter values. """ params = super().get_parameters() params.update({ 'alpha': self.alpha, 'gamma': self.gamma, 'theta': self.theta, - 'd': self.d, - 'dn': self.dn, 'nl': self.nl, - 'mutation_rate': self.mutation_rate, - 'crossover_rate': self.crossover_rate, - 'combination': self.combination + 'f': self.f, + 'cr': self.cr, + 'combination': self.combination, }) return params - def init(self, _task): - r"""Initialize dynamic parameters of algorithm. + def _init_params(self, population_size): + r"""Expand scalar or short list parameters to arrays of length population_size. Args: - _task (Task): Optimization task. + population_size (int): Population size. Returns: - Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray] - 1. Array of `self.alpha` propagated values - 2. Array of `self.gamma` propagated values - 3. Array of `self.theta` propagated values - + Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray]: + 1. Alpha values per individual. + 2. Gamma values per individual. + 3. Theta values per individual. """ - return full_array(self.alpha, self.population_size), full_array(self.gamma, self.population_size), full_array( - self.theta, self.population_size) + return ( + full_array(self.alpha, population_size), + full_array(self.gamma, population_size), + full_array(self.theta, population_size), + ) - @staticmethod - def fickleness_index(x_f, xpb_f, xb_f, alpha): - r"""Get fickleness index. + def _fi(self, x_f, xpb_f, xb_f, alpha): + r"""Calculate fickleness index. + + A high fickleness index means the individual is likely to change its + behaviour (move away from its current position). Args: - x_f (float): Individuals fitness/function value. - xpb_f (float): Individuals personal best fitness/function value. - xb_f (float): Current best found individuals fitness/function value. - alpha (float): Fickleness factor. + x_f (float): Individual's current fitness value. + xpb_f (float): Individual's personal best fitness value. + xb_f (float): Global best fitness value. + alpha (float): Fickleness scaling factor. Returns: - float: Fickleness index. - + float: Fickleness index value. """ - return 1 - alpha * xb_f / x_f - (1 - alpha) * xpb_f / x_f + return 1.0 - alpha * xb_f / x_f - (1.0 - alpha) * xpb_f / x_f - def external_irregularity(self, x_f, xnb_f, gamma): - r"""Get external irregularity index. + def _ei(self, x_f, xnb_f, gamma): + r"""Calculate external irregularity index. + + Measures how different the individual's fitness is from its neighbour's. Args: - x_f (float): Individuals fitness/function value. - xnb_f (float): Individuals new fitness/function value. - gamma (float): External irregularity factor. + x_f (float): Individual's current fitness value. + xnb_f (float): Neighbour's fitness value. + gamma (float): External irregularity scaling factor. Returns: - float: External irregularity index. - + float: External irregularity index value. """ - return 1 - np.exp(-gamma * self.d(x_f, xnb_f)) + return 1.0 - np.exp(-gamma * abs(x_f - xnb_f)) + + def _ii(self, x_f, xpb_f, theta): + r"""Calculate internal irregularity index. - def irregularity_index(self, x_f, xpb_f, theta): - r"""Get internal irregularity index. + Measures how different the individual's current fitness is from its + personal best fitness. Args: - x_f (float): Individuals fitness/function value. - xpb_f (float): Individuals personal best fitness/function value. - theta (float): Internal irregularity factor. + x_f (float): Individual's current fitness value. + xpb_f (float): Individual's personal best fitness value. + theta (float): Internal irregularity scaling factor. Returns: - float: Internal irregularity index - + float: Internal irregularity index value. """ - return 1 - np.exp(-theta * self.d(x_f, xpb_f)) + return 1.0 - np.exp(-theta * abs(x_f - xpb_f)) - def get_best_neighbors(self, i, population, population_fitness, rs): - r"""Get neighbors of individual. + def _get_best_neighbor(self, i, population, population_fitness, rs): + r"""Find the best neighbour of individual *i* within the neighbourhood radius. - Measurement of distance for neighborhood is defined with `self.nl`. - Function for calculating distances is define with `self.dn`. + Neighbourhood is defined by ``self.nl`` (normalised distance threshold) + and ``self.dn`` (distance function in solution space). Args: - i (int): Index of individual for hum we are looking for neighbours. - population (numpy.ndarray): Current population. - population_fitness (numpy.ndarray[float]): Current population fitness/function values. - rs (numpy.ndarray[float]): distance between individuals. + i (int): Index of the focal individual. + population (numpy.ndarray): Current population positions. + population_fitness (numpy.ndarray): Current population fitness values. + rs (float): Search-space diameter used for normalisation. Returns: - numpy.ndarray[int]: Indexes that represent individuals closest to `i`-th individual. - + int: Index of the best neighbour within the neighbourhood. """ - nn = np.asarray([self.dn(population[i], population[j]) / rs for j in range(len(population))]) - return np.argmin(population_fitness[np.where(nn <= self.nl)]) + distances = np.array([ + self.dn(population[i], population[j]) / rs + for j in range(len(population)) + ]) + neighbor_indices = np.where(distances <= self.nl)[0] + return neighbor_indices[np.argmin(population_fitness[neighbor_indices])] - @staticmethod - def update_personal_best(population, population_fitness, personal_best, personal_best_fitness): - r"""Update personal best solution of all individuals in population. + def _update_personal_best(self, population, population_fitness, personal_best, personal_best_fitness): + r"""Update personal best positions for all individuals. Args: - population (numpy.ndarray): Current population. - population_fitness (numpy.ndarray[float]): Current population fitness/function values. - personal_best (numpy.ndarray): Current population best positions. - personal_best_fitness (numpy.ndarray[float]): Current populations best positions fitness/function values. + population (numpy.ndarray): Current population positions. + population_fitness (numpy.ndarray): Current population fitness values. + personal_best (numpy.ndarray): Current personal best positions. + personal_best_fitness (numpy.ndarray): Current personal best fitness values. Returns: - Tuple[numpy.ndarray, numpy.ndarray[float], numpy.ndarray, float]: - 1. New personal best positions for current population. - 2. New personal best positions function/fitness values for current population. - 3. New best individual. - 4. New best individual fitness/function value. - + Tuple[numpy.ndarray, numpy.ndarray]: + 1. Updated personal best positions. + 2. Updated personal best fitness values. """ - ix_pb = np.where(population_fitness < personal_best_fitness) - personal_best[ix_pb], personal_best_fitness[ix_pb] = population[ix_pb], population_fitness[ix_pb] + improved = population_fitness < personal_best_fitness + personal_best[improved] = population[improved].copy() + personal_best_fitness[improved] = population_fitness[improved].copy() return personal_best, personal_best_fitness def init_population(self, task): - r"""Initialize first population and additional arguments. + r"""Initialize population and algorithm state. Args: - task (Task): Optimization task + task (Task): Optimization task. Returns: - Tuple[numpy.ndarray, numpy.ndarray, dict]: - 1. Initialized population - 2. Initialized population fitness/function values - 3. Dict[str, Any]: - * x_best (numpy.ndarray): Initialized populations best positions. - * x_best_fitness (numpy.ndarray): Initialized populations best positions function/fitness values. - * alpha (numpy.ndarray): - * gamma (numpy.ndarray): - * theta (numpy.ndarray): - * rs (float): distance of search space. + Tuple[numpy.ndarray, numpy.ndarray, Dict[str, Any]]: + 1. Initial population positions. + 2. Initial population fitness values. + 3. Additional state: + * personal_best (numpy.ndarray): Personal best positions. + * personal_best_fitness (numpy.ndarray): Personal best fitness values. + * alpha (numpy.ndarray): Per-individual alpha values. + * gamma (numpy.ndarray): Per-individual gamma values. + * theta (numpy.ndarray): Per-individual theta values. + * rs (float): Search-space diameter. See Also: - * :func:`niapy.algorithms.algorithm.Algorithm.init_population` - * :func:`niapy.algorithms.other.aso.AnarchicSocietyOptimization.init` - + * :func:`niapy.algorithms.Algorithm.init_population` """ - population, population_fitness, d = Algorithm.init_population(self, task) - alpha, gamma, theta = self.init(task) - x_best, x_best_fitness = self.update_personal_best(population, task.optimization_type.value * population_fitness, - np.zeros((self.population_size, task.dimension)), - np.full(self.population_size, np.inf)) - d.update({'x_best': x_best, 'x_best_fitness': x_best_fitness, 'alpha': alpha, 'gamma': gamma, 'theta': theta, - 'rs': self.d(task.upper, task.lower)}) - return population, population_fitness, d - - def run_iteration(self, task, population, population_fitness, best_x, best_fitness, **params): - r"""Core function of AnarchicSocietyOptimization algorithm. + population, population_fitness, state = super().init_population(task) + alpha, gamma, theta = self._init_params(self.population_size) + personal_best = population.copy() + personal_best_fitness = population_fitness.copy() + rs = self.dn(task.upper, task.lower) + state.update({ + 'personal_best': personal_best, + 'personal_best_fitness': personal_best_fitness, + 'alpha': alpha, + 'gamma': gamma, + 'theta': theta, + 'rs': rs, + }) + return population, population_fitness, state + + def run_iteration(self, task, population, population_fitness, best_x, best_fitness, + personal_best, personal_best_fitness, alpha, gamma, theta, rs, **params): + r"""Perform one iteration of the Anarchic Society Optimization algorithm. Args: task (Task): Optimization task. - population (numpy.ndarray): Current populations positions. - population_fitness (numpy.ndarray): Current populations function/fitness values. - best_x (numpy.ndarray): Current global best individuals position. - best_fitness (float): Current global best individual function/fitness value. - **params: Additional arguments. + population (numpy.ndarray): Current population positions. + population_fitness (numpy.ndarray): Current population fitness values. + best_x (numpy.ndarray): Global best position found so far. + best_fitness (float): Global best fitness value found so far. + personal_best (numpy.ndarray): Personal best positions. + personal_best_fitness (numpy.ndarray): Personal best fitness values. + alpha (numpy.ndarray): Per-individual fickleness factors. + gamma (numpy.ndarray): Per-individual external irregularity factors. + theta (numpy.ndarray): Per-individual internal irregularity factors. + rs (float): Search-space diameter for normalising distances. + **params: Unused additional parameters. Returns: - Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray, float, dict]: - 1. Initialized population - 2. Initialized population fitness/function values - 3. New global best solution - 4. New global best solutions fitness/objective value - 5. Dict[str, Union[float, int, numpy.ndarray]: - * x_best (numpy.ndarray): Initialized populations best positions. - * x_best_fitness (numpy.ndarray): Initialized populations best positions function/fitness values. - * alpha (numpy.ndarray): - * gamma (numpy.ndarray): - * theta (numpy.ndarray): - * rs (float): distance of search space. - + Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray, float, Dict[str, Any]]: + 1. New population positions. + 2. New population fitness values. + 3. New global best position. + 4. New global best fitness value. + 5. Updated state dictionary. """ - x_best = params.pop('x_best') - x_best_fitness = params.pop('x_best_fitness') - alpha = params.pop('alpha') - gamma = params.pop('gamma') - theta = params.pop('theta') - rs = params.pop('rs') - - x_in = [self.get_best_neighbors(i, population, population_fitness, rs) for i in range(len(population))] - mp_c, mp_s, mp_p = np.asarray( - [self.fickleness_index(population_fitness[i], x_best_fitness[i], best_fitness, alpha[i]) for i in - range(len(population))]), np.asarray( - [self.external_irregularity(population_fitness[i], population_fitness[x_in[i]], gamma[i]) for i in - range(len(population))]), np.asarray( - [self.irregularity_index(population_fitness[i], x_best_fitness[i], theta[i]) for i in range(len(population))]) - x_tmp = np.asarray([self.combination(population[i], x_best[i], best_x, - population[self.integers(len(population), skip=[i])], mp_c[i], mp_s[i], - mp_p[i], self.mutation_rate, self.crossover_rate, task, self.rng) for i in range(len(population))], - dtype=object) - population, population_fitness = np.asarray([x_tmp[i][0] for i in range(len(population))]), np.asarray( - [x_tmp[i][1] for i in range(len(population))]) - x_best, x_best_fitness = self.update_personal_best(population, population_fitness, x_best, x_best_fitness) - best_x, best_fitness = self.get_best(population, population_fitness, best_x, best_fitness) - return population, population_fitness, best_x, best_fitness, {'x_best': x_best, - 'x_best_fitness': x_best_fitness, - 'alpha': alpha, - 'gamma': gamma, - 'theta': theta, - 'rs': rs} + n = len(population) + + # Find best neighbour index for each individual + neighbor_indices = [ + self._get_best_neighbor(i, population, population_fitness, rs) + for i in range(n) + ] + + # Compute movement probability indices + mp_c = np.array([ + self._fi(population_fitness[i], personal_best_fitness[i], best_fitness, alpha[i]) + for i in range(n) + ]) + mp_s = np.array([ + self._ei(population_fitness[i], population_fitness[neighbor_indices[i]], gamma[i]) + for i in range(n) + ]) + mp_p = np.array([ + self._ii(population_fitness[i], personal_best_fitness[i], theta[i]) + for i in range(n) + ]) + + # Generate new positions using the chosen combination strategy + new_population = np.empty_like(population) + new_fitness = np.empty(n) + for i in range(n): + # Pick a random individual different from i + rand_idx = self.integers(n, skip=[i]) + new_population[i], new_fitness[i] = self.combination( + population[i], + personal_best[i], + best_x, + population[rand_idx], + mp_c[i], mp_s[i], mp_p[i], + self.f, self.cr, + task, + self.rng, + ) + + # Update personal bests + personal_best, personal_best_fitness = self._update_personal_best( + new_population, new_fitness, personal_best, personal_best_fitness + ) + + # Update global best + best_x, best_fitness = self.get_best(new_population, new_fitness, best_x, best_fitness) + + return new_population, new_fitness, best_x, best_fitness, { + 'personal_best': personal_best, + 'personal_best_fitness': personal_best_fitness, + 'alpha': alpha, + 'gamma': gamma, + 'theta': theta, + 'rs': rs, + } diff --git a/tests/test_aso.py b/tests/test_aso.py index 44f97d02a..2824134dc 100644 --- a/tests/test_aso.py +++ b/tests/test_aso.py @@ -1,16 +1,13 @@ # encoding=utf8 -from niapy.algorithms.other import AnarchicSocietyOptimization -from niapy.algorithms.other.aso import elitism, sequential, crossover +from niapy.algorithms.other.aso import AnarchicSocietyOptimization, elitism, sequential, crossover from tests.test_algorithm import AlgorithmTestCase, MyProblem -class ASOTestCase(AlgorithmTestCase): +class ASOElitismTestCase(AlgorithmTestCase): def setUp(self): AlgorithmTestCase.setUp(self) self.algo = AnarchicSocietyOptimization - -class ASOElitismTestCase(ASOTestCase): def test_custom(self): aso_custom = self.algo(population_size=10, combination=elitism, seed=self.seed) aso_customc = self.algo(population_size=10, combination=elitism, seed=self.seed) @@ -23,6 +20,10 @@ def test_griewank(self): class ASOSequentialTestCase(AlgorithmTestCase): + def setUp(self): + AlgorithmTestCase.setUp(self) + self.algo = AnarchicSocietyOptimization + def test_custom(self): aso_custom = self.algo(population_size=10, combination=sequential, seed=self.seed) aso_customc = self.algo(population_size=10, combination=sequential, seed=self.seed) @@ -35,6 +36,10 @@ def test_griewank(self): class ASOCrossoverTestCase(AlgorithmTestCase): + def setUp(self): + AlgorithmTestCase.setUp(self) + self.algo = AnarchicSocietyOptimization + def test_custom(self): aso_custom = self.algo(population_size=10, combination=crossover, seed=self.seed) aso_customc = self.algo(population_size=10, combination=crossover, seed=self.seed)