Edge case for converting fitness to minimization

Avoid catastrophic cancellations
2020-11-09 16:02:01 -05:00
parent ce0d879f82
commit 9c455957f2
1 changed files with 4 additions and 1 deletions
--- a/src/EasyGA.py
+++ b/src/EasyGA.py
@ -141,7 +141,10 @@ class GA(Attributes):
        if self.target_fitness_type == 'max': return fitness_value
        max_fitness = self.population.get_chromosome(-1).get_fitness()
        min_fitness = self.population.get_chromosome(0).get_fitness()
-        return max_fitness - fitness_value + min_fitness
+        if min_fitness / max_fitness < 1e-5:
+            return -fitness_value
+        else:
+            return max_fitness - fitness_value + min_fitness


    def print_generation(self):