Module history

Classes

class History

A representation of the action history for a prisoner's dilemma actioner. The history contains a "c" for cooperation and a "d" for defection.

Source code

class History:
    """
    A representation of the action history for a prisoner's dilemma actioner.
    The history contains a "c" for cooperation and a "d" for defection.
    """
    def __init__(self):
        self.history = []

    def get_length(self):
        """Returns the number of actions in the history"""
        return len(self.history)

    def get_most_recent(self):
        """Returns the most recent action (equivalent to `get_past_action(1)`)"""
        if len(self.history) == 0:
            raise RuntimeError("cannot get the most recent action from an empty history")
        return self.history[-1]

    def get_past_action(self, n):
        """Returns the action taken `n` rounds ago"""
        if len(self.history) < n:
            raise RuntimeError("No past action {} rounds ago for a history of length {}".format(n, len(self.history)))
        return self.history[-n]

    def get_num_defects(self):
        """Returns the number of defections in the history"""
        return self.history.count('d')

    def get_num_coops(self):
        """Returns the number of cooperations in the history"""
        return self.history.count('c')

    def has_recent_defect(self, n):
        """Returns `True` if there was a defection in the last `n` actions, otherwise returns `False`"""
        return 'd' in self.history[-n:]

    def has_recent_coop(self, n):
        """Returns `True` if there was a cooperation in the last `n` actions, otherwise returns `False`"""
        return 'c' in self.history[-n:]

    def add_action(self, action):
        """Adds `action` to the end of the history"""
        if action != 'c' and action != 'd':
            raise ValueError("action must be either 'c' or 'd', {} given".format(action))
        self.history.append(action)

    def __iter__(self):
        return iter(self.history)

    def __repr__(self):
        return repr(self.history)

Methods

def add_action(self, action)

Adds action to the end of the history

Source code

def add_action(self, action):
    """Adds `action` to the end of the history"""
    if action != 'c' and action != 'd':
        raise ValueError("action must be either 'c' or 'd', {} given".format(action))
    self.history.append(action)

def get_length(self)

Returns the number of actions in the history

Source code

def get_length(self):
    """Returns the number of actions in the history"""
    return len(self.history)

def get_most_recent(self)

Returns the most recent action (equivalent to get_past_action(1))

Source code

def get_most_recent(self):
    """Returns the most recent action (equivalent to `get_past_action(1)`)"""
    if len(self.history) == 0:
        raise RuntimeError("cannot get the most recent action from an empty history")
    return self.history[-1]

def get_num_coops(self)

Returns the number of cooperations in the history

Source code

def get_num_coops(self):
    """Returns the number of cooperations in the history"""
    return self.history.count('c')

def get_num_defects(self)

Returns the number of defections in the history

Source code

def get_num_defects(self):
    """Returns the number of defections in the history"""
    return self.history.count('d')

def get_past_action(self, n)

Returns the action taken n rounds ago

Source code

def get_past_action(self, n):
    """Returns the action taken `n` rounds ago"""
    if len(self.history) < n:
        raise RuntimeError("No past action {} rounds ago for a history of length {}".format(n, len(self.history)))
    return self.history[-n]

def has_recent_coop(self, n)

Returns True if there was a cooperation in the last n actions, otherwise returns False

Source code

def has_recent_coop(self, n):
    """Returns `True` if there was a cooperation in the last `n` actions, otherwise returns `False`"""
    return 'c' in self.history[-n:]

def has_recent_defect(self, n)

Returns True if there was a defection in the last n actions, otherwise returns False

Source code

def has_recent_defect(self, n):
    """Returns `True` if there was a defection in the last `n` actions, otherwise returns `False`"""
    return 'd' in self.history[-n:]