From 8c024a0290fcd9185aa75b5ee5aa5fd2cacbfa0c Mon Sep 17 00:00:00 2001
From: SimpleArt <71458112+SimpleArt@users.noreply.github.com>
Date: Fri, 4 Dec 2020 14:26:18 -0500
Subject: [PATCH] Added distance attribute

---
 src/EasyGA.py     |  4 ++--
 src/attributes.py | 11 +++++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/EasyGA.py b/src/EasyGA.py
index e084719..d460ffd 100644
--- a/src/EasyGA.py
+++ b/src/EasyGA.py
@@ -126,7 +126,7 @@ class GA(Attributes):
 
         # Difference between best and i-th chromosomes
         best_chromosome = self.population[0]
-        tol = lambda i: sqrt(abs(best_chromosome.fitness - self.population[i].fitness))
+        tol = lambda i: self.dist(best_chromosome, self.population[i])
 
         # Change rates with:
         multiplier = 1 + self.adapt_probability_rate
@@ -185,7 +185,7 @@ class GA(Attributes):
 
         # Difference between best and i-th chromosomes
         best_chromosome = self.population[0]
-        tol = lambda i: sqrt(abs(best_chromosome.fitness - self.population[i].fitness))
+        tol = lambda i: self.dist(best_chromosome, self.population[i])
 
         # First non-zero tolerance after amount_converged/4
         for i in range(amount_converged//4, len(self.population)):
diff --git a/src/attributes.py b/src/attributes.py
index 864541b..d072f1e 100644
--- a/src/attributes.py
+++ b/src/attributes.py
@@ -1,3 +1,6 @@
+# Import square root function for ga.adapt()
+from math import sqrt
+
 import random
 import sqlite3
 from copy import deepcopy
@@ -75,6 +78,7 @@ class Attributes:
             min_selection_probability    = 0.01,
             min_chromosome_mutation_rate = 0.01,
             min_gene_mutation_rate       = None,
+            dist                         = None,
             initialization_impl          = Initialization_Methods.random_initialization,
             fitness_function_impl        = Fitness_Examples.is_it_5,
             make_population              = create_population,
@@ -132,6 +136,13 @@ class Attributes:
         self.min_chromosome_mutation_rate = min_chromosome_mutation_rate
         self.min_gene_mutation_rate       = gene_mutation_rate if (min_gene_mutation_rate is None) else min_gene_mutation_rate
 
+        # Distance between two chromosomes
+        if dist is None:
+            self.dist = lambda chromosome_1, chromosome_2:\
+                sqrt(abs(chromosome_1.fitness - chromosome_2.fitness))
+        else:
+            self.dist = dist
+
         # Mutation variables
         self.chromosome_mutation_rate = deepcopy(chromosome_mutation_rate)
         self.gene_mutation_rate       = deepcopy(gene_mutation_rate)