Source code for axelrod.strategies.selfsteem

from math import pi, sin

from axelrod.action import Action
from axelrod.player import Player

C, D = Action.C, Action.D


[docs]class SelfSteem(Player): """ This strategy is based on the feeling with the same name. It is modeled on the sine curve(f = sin( 2* pi * n / 10 )), which varies with the current iteration. If f > 0.95, 'ego' of the algorithm is inflated; always defects. If 0.95 > abs(f) > 0.3, rational behavior; follows TitForTat algortithm. If 0.3 > f > -0.3; random behavior. If f < -0.95, algorithm is at rock bottom; always cooperates. Futhermore, the algorithm implements a retaliation policy, if the opponent defects; the sin curve is shifted. But due to lack of further information, this implementation does not include a sin phase change. Names: - SelfSteem: [Andre2013]_ """ name = "SelfSteem" classifier = { "memory_depth": float("inf"), "stochastic": True, "long_run_time": False, "inspects_source": False, "manipulates_source": False, "manipulates_state": False, }
[docs] def strategy(self, opponent: Player) -> Action: turns_number = len(self.history) sine_value = sin(2 * pi * turns_number / 10) if sine_value > 0.95: return D if abs(sine_value) < 0.95 and abs(sine_value) > 0.3: return opponent.history[-1] if sine_value < 0.3 and sine_value > -0.3: return self._random.random_choice() return C