Obtain a repeated game
Given a game in Nashpy
it is possible to create a new game by repeating
it as described in Repeated Games:
>>> import nashpy as nash
>>> import nashpy.repeated_games
>>> import numpy as np
>>> A = np.array([[1, -1], [-1, 1]])
>>> matching_pennies = nash.Game(A)
>>> repeated_matching_pennies = nash.repeated_games.obtain_repeated_game(game=matching_pennies, repetitions=2)
>>> repeated_matching_pennies
Zero sum game with payoff matrices:
Row player:
[[ 2. 2. 2. ... 0. -2. -2.]
[ 2. 2. 2. ... 0. -2. -2.]
[ 2. 2. 2. ... 0. -2. -2.]
...
[ 0. 0. 0. ... 2. 0. 2.]
[-2. -2. -2. ... 0. 2. 0.]
[-2. -2. -2. ... 2. 0. 2.]]
Column player:
[[-2. -2. -2. ... 0. 2. 2.]
[-2. -2. -2. ... 0. 2. 2.]
[-2. -2. -2. ... 0. 2. 2.]
...
[ 0. 0. 0. ... -2. 0. -2.]
[ 2. 2. 2. ... 0. -2. 0.]
[ 2. 2. 2. ... -2. 0. -2.]]
Note, that these games can become large even for small values of
repetitions
. The above game has payoff matrices with size:
>>> repeated_matching_pennies.payoff_matrices[0].shape
(32, 32)
When studying these large games direct computation of equilibria is unlikely to be computationally efficient. Instead learning algorithms should be used.
It is also to directly obtain a generator containing the strategies, which are mapping from histories of play to actions:
>>> strategies = nash.repeated_games.obtain_strategy_space(A=A, repetitions=2)
>>> next(strategies)
{((), ()): (1.0, 0.0), ((0,), (0,)): (1.0, 0.0), ((0,), (1,)): (1.0, 0.0), ((1,), (0,)): (1.0, 0.0), ((1,), (1,)): (1.0, 0.0)}