Code source de jouets.mafia

# Copyright 2016 Louis Paternault
#
# This file is part of Jouets.
#
# Jouets is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Jouets is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Jouets.  If not, see <http://www.gnu.org/licenses/>.

"""Calcul de probabilités pour le jeu mafia."""

from functools import lru_cache, wraps

VERSION = "0.1.0"

CACHE_SIZE = 1024 ** 2


def arguments_positifs(func):
    """Décorateur qui renvoit 0 si un des arguments est négatif."""

    @wraps(func)
    def wrapper(*args, **kwargs):
        """Fonction renvoyée par le décorateur."""
        for arg in list(args) + list(kwargs.values()):
            if arg < 0:
                return 0
        return func(*args, **kwargs)

    return wrapper


[docs]@lru_cache(CACHE_SIZE) @arguments_positifs def proba_matin(mafieux, innocents, detectives): """Calcule la probabilité que les innocents gagnent, le matin. Les arguments décrivent les joueurs restant un matin donné. """ if mafieux == 0: return 1.0 if mafieux >= innocents + detectives: return 0.0 total = mafieux + innocents + detectives return ( mafieux / total * proba_soir(mafieux - 1, innocents, detectives) + innocents / total * proba_soir(mafieux, innocents - 1, detectives) + detectives / total * proba_soir(mafieux, innocents, detectives - 1) )
[docs]@lru_cache(CACHE_SIZE) @arguments_positifs def proba_soir(mafieux, innocents, detectives): """Calcule la probabilité que les innocents gagnent, le soir. Les arguments décrivent les joueurs restant un soir donné. """ if mafieux == 0: return 1.0 if detectives == 0: return proba_matin(mafieux, innocents - 1, 0) # pylint: disable=line-too-long return ( innocents / (detectives + innocents) * mafieux / (mafieux + innocents) * proba_matin(mafieux - 1, innocents - 1, detectives) + innocents / (detectives + innocents) * innocents / (mafieux + innocents) * proba_matin(mafieux, innocents - 1, detectives) + detectives / (detectives + innocents) * mafieux / (mafieux + innocents) * proba_matin(mafieux - 1, innocents, detectives - 1) + detectives / (detectives + innocents) * innocents / (mafieux + innocents) * proba_matin(mafieux, innocents, detectives - 1) )