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Added extrapolation method

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SimpleArt
2020-11-27 22:10:30 -05:00
parent d845e7fc1b
commit 5407e2ea63
1 changed files with 27 additions and 1 deletions
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28
src/crossover/crossover_methods.py
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@ -173,7 +173,7 @@ class Crossover_Methods:
@genes_to_chromosome
@values_to_genes
def average(ga, parent_1, parent_2):
"""Cross two parents by taking a a weighted average of the genes."""
"""Cross two parents by taking the average of the genes."""
value_iter_1 = parent_1.gene_value_iter
value_iter_2 = parent_2.gene_value_iter
@ -186,3 +186,29 @@ class Crossover_Methods:
yield (value_1+value_2)/2
except:
raise ValueError("Could not take the average of the gene values. Use integer or float genes.")
@genes_to_chromosome
@values_to_genes
def extrapolate(ga, parent_1, parent_2):
"""Cross two parents by extrapolating towards the better parent.
May result in gene values outside the expected domain.
"""
# Swap so that parent 1 is the better parent.
if ga.target_fitness_type == 'min' and parent_1.fitness > parent_2.fitness:
parent_1, parent_2 = parent_2, parent_1
if ga.target_fitness_type == 'max' and parent_1.fitness < parent_2.fitness:
parent_1, parent_2 = parent_2, parent_1
value_iter_1 = parent_1.gene_value_iter
value_iter_2 = parent_2.gene_value_iter
for value_1, value_2 in zip(value_iter_1, value_iter_2):
if type(value_1) == type(value_2) == int:
yield value_1 + (value_1-value_2)//4
else:
try:
yield value_1 + (value_1-value_2)/4
except:
raise ValueError("Could not take the average of the gene values. Use integer or float genes.")