Mahjong
This environment is part of the classic environments. Please read that page first for general information.
| Name | Value |
|---|---|
| Actions | Discrete |
| Agents | 4 |
| Parallel API | false |
| Manual Control | No |
| Action Shape | Discrete(38) |
| Action Values | Discrete(38) |
| Observation Shape | (6, 34, 4) |
| Observation Values | [0, 1] |
| Import | from pettingzoo.classic import mahjong_v0 |
| Agents | agents= ['player_0', 'player_1', 'player_2', 'player_3'] |
Agent Environment Cycle
Mahjong
Mahjong is a tile-based game with 4 players. It uses a deck of 136 tiles that is comprised of 4 identical sets of 34 unique tiles. The objective is to form 4 sets and a pair with the 14th drawn tile. If no player wins, no player receives a reward.
Our implementation wraps RLCard and you can refer to its documentation for additional details. Please cite their work if you use this game in research.
Observation Space
The observation space has a (6, 34, 4) shape with the first index representing the encoding plane. The contents of each plane are described in the table below:
| Plane | Description |
|---|---|
| 0 | Current Player’s hand |
| 1 | Played tiles on the table |
| 2 | Public piles of player_0 |
| 3 | Public piles of player_1 |
| 4 | Public piles of player_2 |
| 5 | Public piles of player_3 |
Encoding per Plane
| Plane Row Index | Description |
|---|---|
| 0 - 8 | Bamboo0: 1, 1: 2, …, 8: 9 |
| 9 - 17 | Characters9: 1, 10: 2, …, 17: 9 |
| 18 - 26 | Dots18: 1, 19: 2, …, 26: 9 |
| 27 | Dragons Green |
| 28 | Dragons Red |
| 29 | Dragons White |
| 30 | Winds East |
| 31 | Winds West |
| 32 | Winds North |
| 33 | Winds South |
| Plane Column Index | Description |
|---|---|
| 0 | Tile Set 1 |
| 1 | Tile Set 2 |
| 2 | Tile Set 3 |
| 3 | Tile Set 4 |
Action Space
The action space, as described by RLCard, is
| Action ID | Action |
|---|---|
| 0 - 8 | Bamboo0: 1, 1: 2, …, 8: 9 |
| 9 - 17 | Characters9: 1, 10: 2, …, 17: 9 |
| 18 - 26 | Dots18: 1, 19: 2, …, 26: 9 |
| 27 | Dragons Green |
| 28 | Dragons Red |
| 29 | Dragons White |
| 30 | Winds East |
| 31 | Winds West |
| 32 | Winds North |
| 33 | Winds South |
| 34 | Pong |
| 35 | Chow |
| 36 | Gong |
| 37 | Stand |
For example, you would use action 34 to pong or action 37 to stand.
Rewards
| Winner | Loser |
|---|---|
| +1 | -1 |
Legal Moves
The legal moves available for each agent, found in env.infos[agent]['legal_moves'], are updated after each step. Taking an illegal move ends the game with a reward of -1 for the illegally moving agent and a reward of 0 for all other agents.