Exemple #1
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    def _mutation(self, child1_weights: np.ndarray, child2_weights: np.ndarray,
                  child1_bias: np.ndarray, child2_bias: np.ndarray) -> None:
        scale = .2
        rand_mutation = random.random()
        mutation_bucket = np.digitize(rand_mutation, self._mutation_bins)

        mutation_rate = self._mutation_rate
        if self.settings['mutation_rate_type'].lower() == 'decaying':
            mutation_rate = mutation_rate / sqrt(self.current_generation + 1)

        # Gaussian
        if mutation_bucket == 0:
            # Mutate weights
            gaussian_mutation(child1_weights, mutation_rate, scale=scale)
            gaussian_mutation(child2_weights, mutation_rate, scale=scale)

            # Mutate bias
            gaussian_mutation(child1_bias, mutation_rate, scale=scale)
            gaussian_mutation(child2_bias, mutation_rate, scale=scale)
        
        # Uniform random
        elif mutation_bucket == 1:
            # Mutate weights
            random_uniform_mutation(child1_weights, mutation_rate, -1, 1)
            random_uniform_mutation(child2_weights, mutation_rate, -1, 1)

            # Mutate bias
            random_uniform_mutation(child1_bias, mutation_rate, -1, 1)
            random_uniform_mutation(child2_bias, mutation_rate, -1, 1)

        else:
            raise Exception('Unable to determine valid mutation based off probabilities.')
Exemple #2
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    def _mutation(self, child1_weights: np.ndarray, child2_weights: np.ndarray,
                  child1_bias: np.ndarray, child2_bias: np.ndarray) -> None:
        mutation_rate = self.config.Mutation.mutation_rate
        scale = self.config.Mutation.gaussian_mutation_scale

        if self.config.Mutation.mutation_rate_type == 'dynamic':
            mutation_rate = mutation_rate / math.sqrt(self.current_generation + 1)
        
        # Mutate weights
        gaussian_mutation(child1_weights, mutation_rate, scale=scale)
        gaussian_mutation(child2_weights, mutation_rate, scale=scale)

        # Mutate bias
        gaussian_mutation(child1_bias, mutation_rate, scale=scale)
        gaussian_mutation(child2_bias, mutation_rate, scale=scale)
Exemple #3
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    def _mutation(self, chromosome: np.ndarray) -> None:
        """
        Randomly decide if we should perform mutation on a gene within the chromosome. This is done in place
        """
        rand_mutation = random.random()
        mutation_bucket = np.digitize(rand_mutation, self._mutation_bins)

        # Gaussian
        if mutation_bucket == 0:
            mutation_rate = get_ga_constant('mutation_rate')
            if get_ga_constant('mutation_rate_type').lower() == 'dynamic':
                mutation_rate = mutation_rate / math.sqrt(
                    self.current_generation + 1)
            gaussian_mutation(chromosome,
                              mutation_rate,
                              scale=get_ga_constant('gaussian_mutation_scale'))

        # Random uniform
        elif mutation_bucket == 1:
            #@TODO: add to this
            pass
        else:
            raise Exception(
                'Unable to determine valid mutation based off probabilities')