Bug in save best solutions

[screetech]

Description

If save_best_solutions = True, the best_solutions list is overwritten after each generation when a new population is being generated. A bug appears on line number 748. Solutions stored in best_solutions are probably just shallow copies, i.e., pointers to population.

What the bug looks like

best_solutions = []
best_solutions = [[9, 10, 5, 9, 9]] # after append on the line 728, it holds first best solution found
best_solutions = [[6, 9, 6, 9, 6]] # after the line 748, original value has been changed (changed after every single generation)

[ahmedfgad]

Thanks.

The bug is fixed by creating a copy of the best solution. This prevents a solution saved in the best_solutions attribute from being changed.

The next line:

best_solution = self.population[best_match_idx, :]

is replaced by this line:

best_solution = self.population[best_match_idx, :].copy()

[ahmedfgad]

PyGAD 2.10.2 is released which addresses this issue. Thank you :)