| Total Complexity | 52 |
| Total Lines | 535 |
| Duplicated Lines | 3.36 % |
| Changes | 0 | ||
Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like NiaPy.algorithms.basic.es often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
| 1 | # encoding=utf8 |
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| 2 | import logging |
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| 3 | from math import ceil |
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| 4 | |||
| 5 | from numpy import argmin, argsort, log, sum, fmax, sqrt, full, exp, eye, diag, apply_along_axis, round, any, asarray, dot, random as rand, tile, inf, where, append |
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| 6 | from numpy.linalg import norm, cholesky as chol, eig, solve, lstsq |
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| 7 | |||
| 8 | from NiaPy.algorithms.algorithm import Algorithm, Individual, defaultIndividualInit |
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| 9 | from NiaPy.util.utility import objects2array |
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| 10 | |||
| 11 | logging.basicConfig() |
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| 12 | logger = logging.getLogger('NiaPy.algorithms.basic') |
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| 13 | logger.setLevel('INFO') |
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| 14 | |||
| 15 | __all__ = ['EvolutionStrategy1p1', 'EvolutionStrategyMp1', 'EvolutionStrategyMpL', 'EvolutionStrategyML', 'CovarianceMatrixAdaptionEvolutionStrategy'] |
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| 16 | |||
| 17 | class IndividualES(Individual): |
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| 18 | r"""Individual for Evolution Strategies. |
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| 19 | |||
| 20 | See Also: |
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| 21 | * :class:`NiaPy.algorithms.Individual` |
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| 22 | """ |
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| 23 | def __init__(self, **kwargs): |
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| 24 | r"""Initialize individual. |
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| 25 | |||
| 26 | Args: |
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| 27 | kwargs (Dict[str, Any]): Additional arguments. |
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| 28 | |||
| 29 | See Also: |
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| 30 | * :func:`NiaPy.algorithms.Individual.__init__` |
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| 31 | """ |
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| 32 | Individual.__init__(self, **kwargs) |
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| 33 | self.rho = kwargs.get('rho', 1) |
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| 34 | |||
| 35 | class EvolutionStrategy1p1(Algorithm): |
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| 36 | r"""Implementation of (1 + 1) evolution strategy algorithm. Uses just one individual. |
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| 37 | |||
| 38 | Algorithm: |
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| 39 | (1 + 1) Evolution Strategy Algorithm |
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| 40 | |||
| 41 | Date: |
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| 42 | 2018 |
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| 43 | |||
| 44 | Authors: |
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| 45 | Klemen Berkovič |
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| 46 | |||
| 47 | License: |
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| 48 | MIT |
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| 49 | |||
| 50 | Reference URL: |
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| 51 | |||
| 52 | Reference paper: |
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| 53 | |||
| 54 | Attributes: |
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| 55 | Name (List[str]): List of strings representing algorithm names. |
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| 56 | mu (int): Number of parents. |
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| 57 | k (int): Number of iterations before checking and fixing rho. |
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| 58 | c_a (float): Search range amplification factor. |
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| 59 | c_r (float): Search range reduction factor. |
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| 60 | |||
| 61 | See Also: |
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| 62 | * :class:`NiaPy.algorithms.Algorithm` |
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| 63 | """ |
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| 64 | Name = ['EvolutionStrategy1p1', 'EvolutionStrategy(1+1)', 'ES(1+1)'] |
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| 65 | |||
| 66 | View Code Duplication | @staticmethod |
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| 67 | def typeParameters(): |
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| 68 | r"""Get dictionary with functions for checking values of parameters. |
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| 69 | |||
| 70 | Returns: |
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| 71 | Dict[str, Callable]: |
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| 72 | * mu (Callable[[int], bool]) |
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| 73 | * k (Callable[[int], bool]) |
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| 74 | * c_a (Callable[[Union[float, int]], bool]) |
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| 75 | * c_r (Callable[[Union[float, int]], bool]) |
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| 76 | * epsilon (Callable[[float], bool]) |
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| 77 | """ |
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| 78 | return { |
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| 79 | 'mu': lambda x: isinstance(x, int) and x > 0, |
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| 80 | 'k': lambda x: isinstance(x, int) and x > 0, |
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| 81 | 'c_a': lambda x: isinstance(x, (float, int)) and x > 1, |
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| 82 | 'c_r': lambda x: isinstance(x, (float, int)) and 0 < x < 1, |
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| 83 | 'epsilon': lambda x: isinstance(x, float) and 0 < x < 1 |
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| 84 | } |
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| 85 | |||
| 86 | def setParameters(self, mu=1, k=10, c_a=1.1, c_r=0.5, epsilon=1e-20, **ukwargs): |
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| 87 | r"""Set the arguments of an algorithm. |
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| 88 | |||
| 89 | Arguments: |
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| 90 | mu (Optional[int]): Number of parents |
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| 91 | k (Optional[int]): Number of iterations before checking and fixing rho |
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| 92 | c_a (Optional[float]): Search range amplification factor |
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| 93 | c_r (Optional[float]): Search range reduction factor |
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| 94 | |||
| 95 | See Also: |
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| 96 | * :func:`NiaPy.algorithms.Algorithm.setParameters` |
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| 97 | """ |
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| 98 | Algorithm.setParameters(self, NP=mu, itype=ukwargs.pop('itype', IndividualES), **ukwargs) |
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| 99 | self.mu, self.k, self.c_a, self.c_r, self.epsilon = mu, k, c_a, c_r, epsilon |
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| 100 | |||
| 101 | def mutate(self, x, rho): |
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| 102 | r"""Mutate individual. |
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| 103 | |||
| 104 | Args: |
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| 105 | x (Individual): Current individual. |
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| 106 | rho (float): Current standard deviation. |
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| 107 | |||
| 108 | Returns: |
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| 109 | Individual: Mutated individual. |
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| 110 | """ |
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| 111 | return x + self.normal(0, rho, len(x)) |
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| 112 | |||
| 113 | def updateRho(self, rho, k): |
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| 114 | r"""Update standard deviation. |
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| 115 | |||
| 116 | Args: |
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| 117 | rho (float): Current standard deviation. |
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| 118 | k (int): Number of succesfull mutations. |
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| 119 | |||
| 120 | Returns: |
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| 121 | float: New standard deviation. |
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| 122 | """ |
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| 123 | phi = k / self.k |
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| 124 | if phi < 0.2: return self.c_r * rho if rho > self.epsilon else 1 |
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| 125 | elif phi > 0.2: return self.c_a * rho if rho > self.epsilon else 1 |
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| 126 | else: return rho |
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| 127 | |||
| 128 | def initPopulation(self, task): |
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| 129 | r"""Initialize starting individual. |
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| 130 | |||
| 131 | Args: |
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| 132 | task (Task): Optimization task. |
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| 133 | |||
| 134 | Returns: |
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| 135 | Tuple[Individual, float, Dict[str, Any]]: |
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| 136 | 1, Initialized individual. |
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| 137 | 2, Initialized individual fitness/function value. |
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| 138 | 3. Additional arguments: |
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| 139 | * ki (int): Number of successful rho update. |
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| 140 | """ |
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| 141 | c, ki = IndividualES(task=task, rnd=self.Rand), 0 |
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| 142 | return c, c.f, {'ki': ki} |
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| 143 | |||
| 144 | def runIteration(self, task, c, fpop, xb, fxb, ki, **dparams): |
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| 145 | r"""Core function of EvolutionStrategy(1+1) algorithm. |
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| 146 | |||
| 147 | Args: |
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| 148 | task (Task): Optimization task. |
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| 149 | pop (Individual): Current position. |
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| 150 | fpop (float): Current position function/fitness value. |
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| 151 | xb (Individual): Global best position. |
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| 152 | fxb (float): Global best function/fitness value. |
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| 153 | ki (int): Number of successful updates before rho update. |
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| 154 | **dparams (Dict[str, Any]): Additional arguments. |
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| 155 | |||
| 156 | Returns: |
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| 157 | Tuple[Individual, float, Individual, float, Dict[str, Any]]: |
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| 158 | 1, Initialized individual. |
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| 159 | 2, Initialized individual fitness/function value. |
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| 160 | 3. New global best solution. |
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| 161 | 4. New global best soluitons fitness/objective value. |
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| 162 | 5. Additional arguments: |
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| 163 | * ki (int): Number of successful rho update. |
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| 164 | """ |
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| 165 | if task.Iters % self.k == 0: c.rho, ki = self.updateRho(c.rho, ki), 0 |
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| 166 | cn = objects2array([task.repair(self.mutate(c.x, c.rho), self.Rand) for _i in range(self.mu)]) |
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| 167 | cn_f = asarray([task.eval(cn[i]) for i in range(len(cn))]) |
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| 168 | ib = argmin(cn_f) |
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| 169 | if cn_f[ib] < c.f: |
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| 170 | c.x, c.f, ki = cn[ib], cn_f[ib], ki + 1 |
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| 171 | if cn_f[ib] < fxb: xb, fxb = self.getBest(cn[ib], cn_f[ib], xb, fxb) |
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| 172 | return c, c.f, xb, fxb, {'ki': ki} |
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| 173 | |||
| 174 | class EvolutionStrategyMp1(EvolutionStrategy1p1): |
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| 175 | r"""Implementation of (mu + 1) evolution strategy algorithm. Algorithm creates mu mutants but into new generation goes only one individual. |
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| 176 | |||
| 177 | Algorithm: |
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| 178 | (:math:`\mu + 1`) Evolution Strategy Algorithm |
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| 179 | |||
| 180 | Date: |
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| 181 | 2018 |
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| 182 | |||
| 183 | Authors: |
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| 184 | Klemen Berkovič |
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| 185 | |||
| 186 | License: |
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| 187 | MIT |
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| 188 | |||
| 189 | Reference URL: |
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| 190 | |||
| 191 | Reference paper: |
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| 192 | |||
| 193 | Attributes: |
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| 194 | Name (List[str]): List of strings representing algorithm names. |
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| 195 | |||
| 196 | See Also: |
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| 197 | * :class:`NiaPy.algorithms.basic.EvolutionStrategy1p1` |
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| 198 | """ |
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| 199 | Name = ['EvolutionStrategyMp1', 'EvolutionStrategy(mu+1)', 'ES(m+1)'] |
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| 200 | |||
| 201 | def setParameters(self, **kwargs): |
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| 202 | r"""Set core parameters of EvolutionStrategy(mu+1) algorithm. |
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| 203 | |||
| 204 | Args: |
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| 205 | **kwargs (Dict[str, Any]): |
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| 206 | |||
| 207 | See Also: |
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| 208 | * :func:`NiaPy.algorithms.basic.EvolutionStrategy1p1.setParameters` |
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| 209 | """ |
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| 210 | mu = kwargs.pop('mu', 40) |
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| 211 | EvolutionStrategy1p1.setParameters(self, mu=mu, **kwargs) |
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| 212 | |||
| 213 | class EvolutionStrategyMpL(EvolutionStrategy1p1): |
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| 214 | r"""Implementation of (mu + lambda) evolution strategy algorithm. Mulation creates lambda individual. Lambda individual compete with mu individuals for survival, so only mu individual go to new generation. |
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| 215 | |||
| 216 | Algorithm: |
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| 217 | (:math:`\mu + \lambda`) Evolution Strategy Algorithm |
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| 218 | |||
| 219 | Date: |
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| 220 | 2018 |
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| 221 | |||
| 222 | Authors: |
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| 223 | Klemen Berkovič |
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| 224 | |||
| 225 | License: |
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| 226 | MIT |
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| 227 | |||
| 228 | Reference URL: |
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| 229 | |||
| 230 | Reference paper: |
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| 231 | |||
| 232 | Attributes: |
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| 233 | Name (List[str]): List of strings representing algorithm names |
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| 234 | lam (int): TODO |
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| 235 | |||
| 236 | See Also: |
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| 237 | * :class:`NiaPy.algorithms.basic.EvolutionStrategy1p1` |
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| 238 | """ |
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| 239 | Name = ['EvolutionStrategyMpL', 'EvolutionStrategy(mu+lambda)', 'ES(m+l)'] |
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| 240 | |||
| 241 | @staticmethod |
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| 242 | def typeParameters(): |
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| 243 | r"""TODO. |
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| 244 | |||
| 245 | Returns: |
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| 246 | Dict[str, Any]: |
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| 247 | * lam (Callable[[int], bool]): TODO. |
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| 248 | |||
| 249 | See Also: |
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| 250 | * :func:`NiaPy.algorithms.basic.EvolutionStrategy1p1` |
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| 251 | """ |
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| 252 | d = EvolutionStrategy1p1.typeParameters() |
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| 253 | d['lam'] = lambda x: isinstance(x, int) and x > 0 |
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| 254 | return d |
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| 255 | |||
| 256 | def setParameters(self, lam=45, **ukwargs): |
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| 257 | r"""Set the arguments of an algorithm. |
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| 258 | |||
| 259 | Arguments: |
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| 260 | lam (int): Number of new individual generated by mutation. |
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| 261 | |||
| 262 | See Also: |
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| 263 | * :func:`NiaPy.algorithms.basic.es.EvolutionStrategy1p1.setParameters` |
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| 264 | """ |
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| 265 | EvolutionStrategy1p1.setParameters(self, InitPopFunc=defaultIndividualInit, **ukwargs) |
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| 266 | self.lam = lam |
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| 267 | |||
| 268 | def updateRho(self, pop, k): |
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| 269 | r"""Update standard deviation for population. |
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| 270 | |||
| 271 | Args: |
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| 272 | pop (numpy.ndarray[Individual]): Current population. |
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| 273 | k (int): Number of successful mutations. |
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| 274 | """ |
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| 275 | phi = k / self.k |
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| 276 | if phi < 0.2: |
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| 277 | for i in pop: i.rho = self.c_r * i.rho |
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| 278 | elif phi > 0.2: |
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| 279 | for i in pop: i.rho = self.c_a * i.rho |
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| 280 | |||
| 281 | def changeCount(self, c, cn): |
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| 282 | r"""Update number of successful mutations for population. |
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| 283 | |||
| 284 | Args: |
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| 285 | c (numpy.ndarray[Individual]): Current population. |
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| 286 | cn (numpy.ndarray[Individual]): New population. |
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| 287 | |||
| 288 | Returns: |
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| 289 | int: Number of successful mutations. |
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| 290 | """ |
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| 291 | k = 0 |
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| 292 | for e in cn: |
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| 293 | if e not in c: k += 1 |
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| 294 | return k |
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| 295 | |||
| 296 | def mutateRand(self, pop, task): |
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| 297 | r"""Mutate random individual form population. |
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| 298 | |||
| 299 | Args: |
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| 300 | pop (numpy.ndarray[Individual]): Current population. |
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| 301 | task (Task): Optimization task. |
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| 302 | |||
| 303 | Returns: |
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| 304 | numpy.ndarray: Random individual from population that was mutated. |
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| 305 | """ |
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| 306 | i = self.randint(self.mu) |
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| 307 | return task.repair(self.mutate(pop[i].x, pop[i].rho), rnd=self.Rand) |
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| 308 | |||
| 309 | def initPopulation(self, task): |
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| 310 | r"""Initialize starting population. |
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| 311 | |||
| 312 | Args: |
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| 313 | task (Task): Optimization task. |
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| 314 | |||
| 315 | Returns: |
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| 316 | Tuple[numpy.ndarray[Individual], numpy.ndarray[float], Dict[str, Any]]: |
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| 317 | 1. Initialized populaiton. |
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| 318 | 2. Initialized populations function/fitness values. |
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| 319 | 3. Additional arguments: |
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| 320 | * ki (int): Number of successful mutations. |
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| 321 | |||
| 322 | See Also: |
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| 323 | * :func:`NiaPy.algorithms.algorithm.Algorithm.initPopulation` |
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| 324 | """ |
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| 325 | c, fc, d = Algorithm.initPopulation(self, task) |
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| 326 | d.update({'ki': 0}) |
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| 327 | return c, fc, d |
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| 328 | |||
| 329 | def runIteration(self, task, c, fpop, xb, fxb, ki, **dparams): |
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| 330 | r"""Core function of EvolutionStrategyMpL algorithm. |
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| 331 | |||
| 332 | Args: |
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| 333 | task (Task): Optimization task. |
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| 334 | c (numpy.ndarray): Current population. |
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| 335 | fpop (numpy.ndarray): Current populations fitness/function values. |
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| 336 | xb (numpy.ndarray): Global best individual. |
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| 337 | fxb (float): Global best individuals fitness/function value. |
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| 338 | ki (int): Number of successful mutations. |
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| 339 | **dparams (Dict[str, Any]): Additional arguments. |
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| 340 | |||
| 341 | Returns: |
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| 342 | Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray, float, Dict[str, Any]]: |
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| 343 | 1. New population. |
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| 344 | 2. New populations function/fitness values. |
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| 345 | 3. New global best solution. |
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| 346 | 4. New global best solutions fitness/objective value. |
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| 347 | 5. Additional arguments: |
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| 348 | * ki (int): Number of successful mutations. |
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| 349 | """ |
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| 350 | if task.Iters % self.k == 0: _, ki = self.updateRho(c, ki), 0 |
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| 351 | cn = objects2array([IndividualES(x=self.mutateRand(c, task), task=task, rnd=self.Rand) for _ in range(self.lam)]) |
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| 352 | cn = append(cn, c) |
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| 353 | cn = objects2array([cn[i] for i in argsort([i.f for i in cn])[:self.mu]]) |
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| 354 | ki += self.changeCount(c, cn) |
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| 355 | fcn = asarray([x.f for x in cn]) |
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| 356 | xb, fxb = self.getBest(cn, fcn, xb, fxb) |
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| 357 | return cn, fcn, xb, fxb, {'ki': ki} |
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| 358 | |||
| 359 | class EvolutionStrategyML(EvolutionStrategyMpL): |
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| 360 | r"""Implementation of (mu, lambda) evolution strategy algorithm. Algorithm is good for dynamic environments. Mu individual create lambda chields. Only best mu chields go to new generation. Mu parents are discarded. |
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| 361 | |||
| 362 | Algorithm: |
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| 363 | (:math:`\mu + \lambda`) Evolution Strategy Algorithm |
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| 364 | |||
| 365 | Date: |
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| 366 | 2018 |
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| 367 | |||
| 368 | Authors: |
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| 369 | Klemen Berkovič |
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| 370 | |||
| 371 | License: |
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| 372 | MIT |
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| 373 | |||
| 374 | Reference URL: |
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| 375 | |||
| 376 | Reference paper: |
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| 377 | |||
| 378 | Attributes: |
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| 379 | Name (List[str]): List of strings representing algorithm names |
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| 380 | |||
| 381 | See Also: |
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| 382 | * :class:`NiaPy.algorithm.basic.es.EvolutionStrategyMpL` |
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| 383 | """ |
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| 384 | Name = ['EvolutionStrategyML', 'EvolutionStrategy(mu,lambda)', 'ES(m,l)'] |
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| 385 | |||
| 386 | def newPop(self, pop): |
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| 387 | r"""Return new population. |
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| 388 | |||
| 389 | Args: |
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| 390 | pop (numpy.ndarray): Current population. |
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| 391 | |||
| 392 | Returns: |
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| 393 | numpy.ndarray: New population. |
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| 394 | """ |
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| 395 | pop_s = argsort([i.f for i in pop]) |
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| 396 | if self.mu < self.lam: return objects2array([pop[i] for i in pop_s[:self.mu]]) |
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| 397 | npop = list() |
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| 398 | for i in range(int(ceil(float(self.mu) / self.lam))): npop.extend(pop[:self.lam if (self.mu - i * self.lam) >= self.lam else self.mu - i * self.lam]) |
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| 399 | return objects2array(npop) |
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| 400 | |||
| 401 | def initPopulation(self, task): |
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| 402 | r"""Initialize starting population. |
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| 403 | |||
| 404 | Args: |
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| 405 | task (Task): Optimization task. |
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| 406 | |||
| 407 | Returns: |
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| 408 | Tuple[numpy.ndarray[Individual], numpy.ndarray[float], Dict[str, Any]]: |
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| 409 | 1. Initialized population. |
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| 410 | 2. Initialized populations fitness/function values. |
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| 411 | 2. Additional arguments. |
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| 412 | |||
| 413 | See Also: |
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| 414 | * :func:`NiaPy.algorithm.basic.es.EvolutionStrategyMpL.initPopulation` |
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| 415 | """ |
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| 416 | c, fc, _ = EvolutionStrategyMpL.initPopulation(self, task) |
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| 417 | return c, fc, {} |
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| 418 | |||
| 419 | def runIteration(self, task, c, fpop, xb, fxb, **dparams): |
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| 420 | r"""Core function of EvolutionStrategyML algorithm. |
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| 421 | |||
| 422 | Args: |
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| 423 | task (Task): Optimization task. |
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| 424 | c (numpy.ndarray): Current population. |
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| 425 | fpop (numpy.ndarray): Current population fitness/function values. |
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| 426 | xb (numpy.ndarray): Global best individual. |
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| 427 | fxb (float): Global best individuals fitness/function value. |
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| 428 | **dparams Dict[str, Any]: Additional arguments. |
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| 429 | |||
| 430 | Returns: |
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| 431 | Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray, float, Dict[str, Any]]: |
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| 432 | 1. New population. |
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| 433 | 2. New populations fitness/function values. |
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| 434 | 3. New global best solution. |
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| 435 | 4. New global best solutions fitness/objective value. |
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| 436 | 5. Additional arguments. |
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| 437 | """ |
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| 438 | cn = objects2array([IndividualES(x=self.mutateRand(c, task), task=task, rand=self.Rand) for _ in range(self.lam)]) |
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| 439 | c = self.newPop(cn) |
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| 440 | fc = asarray([x.f for x in c]) |
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| 441 | xb, fxb = self.getBest(c, fc, xb, fxb) |
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| 442 | return c, fc, xb, fxb, {} |
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| 443 | |||
| 444 | def CovarianceMaatrixAdaptionEvolutionStrategyF(task, epsilon=1e-20, rnd=rand): |
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| 445 | lam, alpha_mu, hs, sigma0 = (4 + round(3 * log(task.D))) * 10, 2, 0, 0.3 * task.bcRange() |
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| 446 | mu = int(round(lam / 2)) |
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| 447 | w = log(mu + 0.5) - log(range(1, mu + 1)) |
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| 448 | w = w / sum(w) |
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| 449 | mueff = 1 / sum(w ** 2) |
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| 450 | cs = (mueff + 2) / (task.D + mueff + 5) |
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| 451 | ds = 1 + cs + 2 * max(sqrt((mueff - 1) / (task.D + 1)) - 1, 0) |
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| 452 | ENN = sqrt(task.D) * (1 - 1 / (4 * task.D) + 1 / (21 * task.D ** 2)) |
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| 453 | cc, c1 = (4 + mueff / task.D) / (4 + task.D + 2 * mueff / task.D), 2 / ((task.D + 1.3) ** 2 + mueff) |
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| 454 | cmu, hth = min(1 - c1, alpha_mu * (mueff - 2 + 1 / mueff) / ((task.D + 2) ** 2 + alpha_mu * mueff / 2)), (1.4 + 2 / (task.D + 1)) * ENN |
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| 455 | ps, pc, C, sigma, M = full(task.D, 0.0), full(task.D, 0.0), eye(task.D), sigma0, full(task.D, 0.0) |
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| 456 | x = rnd.uniform(task.bcLower(), task.bcUpper()) |
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| 457 | x_f = task.eval(x) |
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| 458 | while not task.stopCondI(): |
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| 459 | pop_step = asarray([rnd.multivariate_normal(full(task.D, 0.0), C) for _ in range(int(lam))]) |
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| 460 | pop = asarray([task.repair(x + sigma * ps, rnd) for ps in pop_step]) |
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| 461 | pop_f = apply_along_axis(task.eval, 1, pop) |
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| 462 | isort = argsort(pop_f) |
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| 463 | pop, pop_f, pop_step = pop[isort[:mu]], pop_f[isort[:mu]], pop_step[isort[:mu]] |
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| 464 | if pop_f[0] < x_f: x, x_f = pop[0], pop_f[0] |
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| 465 | M = sum(w * pop_step.T, axis=1) |
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| 466 | ps = solve(chol(C).conj() + epsilon, ((1 - cs) * ps + sqrt(cs * (2 - cs) * mueff) * M + epsilon).T)[0].T |
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| 467 | sigma *= exp(cs / ds * (norm(ps) / ENN - 1)) ** 0.3 |
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| 468 | ifix = where(sigma == inf) |
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| 469 | if any(ifix): sigma[ifix] = sigma0 |
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| 470 | if norm(ps) / sqrt(1 - (1 - cs) ** (2 * (task.Iters + 1))) < hth: hs = 1 |
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| 471 | else: hs = 0 |
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| 472 | delta = (1 - hs) * cc * (2 - cc) |
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| 473 | pc = (1 - cc) * pc + hs * sqrt(cc * (2 - cc) * mueff) * M |
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| 474 | C = (1 - c1 - cmu) * C + c1 * (tile(pc, [len(pc), 1]) * tile(pc.reshape([len(pc), 1]), [1, len(pc)]) + delta * C) |
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| 475 | for i in range(mu): C += cmu * w[i] * tile(pop_step[i], [len(pop_step[i]), 1]) * tile(pop_step[i].reshape([len(pop_step[i]), 1]), [1, len(pop_step[i])]) |
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| 476 | E, V = eig(C) |
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| 477 | if any(E < epsilon): |
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| 478 | E = fmax(E, 0) |
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| 479 | C = lstsq(V.T, dot(V, diag(E)).T, rcond=None)[0].T |
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| 480 | return x, x_f |
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| 481 | |||
| 482 | class CovarianceMatrixAdaptionEvolutionStrategy(Algorithm): |
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| 483 | r"""Implementation of (mu, lambda) evolution strategy algorithm. Algorithm is good for dynamic environments. Mu individual create lambda chields. Only best mu chields go to new generation. Mu parents are discarded. |
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| 484 | |||
| 485 | Algorithm: |
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| 486 | (:math:`\mu + \lambda`) Evolution Strategy Algorithm |
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| 487 | |||
| 488 | Date: |
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| 489 | 2018 |
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| 490 | |||
| 491 | Authors: |
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| 492 | Klemen Berkovič |
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| 493 | |||
| 494 | License: |
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| 495 | MIT |
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| 496 | |||
| 497 | Reference URL: |
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| 498 | https://arxiv.org/abs/1604.00772 |
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| 499 | |||
| 500 | Reference paper: |
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| 501 | Hansen, Nikolaus. "The CMA evolution strategy: A tutorial." arXiv preprint arXiv:1604.00772 (2016). |
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| 502 | |||
| 503 | Attributes: |
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| 504 | Name (List[str]): List of names representing algorithm names |
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| 505 | epsilon (float): TODO |
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| 506 | """ |
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| 507 | Name = ['CovarianceMatrixAdaptionEvolutionStrategy', 'CMA-ES', 'CMAES'] |
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| 508 | epsilon = 1e-20 |
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| 509 | |||
| 510 | @staticmethod |
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| 511 | def typeParameters(): return { |
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| 512 | 'epsilon': lambda x: isinstance(x, (float, int)) and 0 < x < 1 |
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| 513 | } |
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| 514 | |||
| 515 | def setParameters(self, epsilon=1e-20, **ukwargs): |
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| 516 | r"""Set core parameters of CovarianceMatrixAdaptionEvolutionStrategy algorithm. |
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| 517 | |||
| 518 | Args: |
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| 519 | epsilon (float): Small number. |
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| 520 | **ukwargs (Dict[str, Any]): Additional arguments. |
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| 521 | """ |
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| 522 | Algorithm.setParameters(self, **ukwargs) |
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| 523 | self.epsilon = epsilon |
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| 524 | |||
| 525 | def runTask(self, task): |
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| 526 | r"""TODO. |
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| 527 | |||
| 528 | Args: |
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| 529 | task (Task): Optimization task. |
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| 530 | |||
| 531 | Returns: |
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| 532 | TODO. |
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| 533 | """ |
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| 534 | return CovarianceMaatrixAdaptionEvolutionStrategyF(task, self.epsilon, rnd=self.Rand) |
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| 535 | |||
| 537 |