English

Python 3.8+ is supported.

If you need Python 2 support you can use v1.1.11 version of the library.

The library contains various tools (shanten, agari, hand calculation) for the Japanese version of mahjong (riichi mahjong).

Riichi mahjong hands calculation

It supports optional features like:

Feature	Keyword parameter	Default value
Disable or enable open tanyao yaku	has_open_tanyao	False
Disable or enable aka dora in the hand	has_aka_dora	False
Disable or enable double yakuman (like suuanko tanki)	has_double_yakuman	True
Settings for different kazoe yakuman calculation (it сan be an yakuman or a sanbaiman)	kazoe_limit	HandConstants.KAZOE_LIMITED
Support kiriage mangan	kiriage	False
Allow to disable additional +2 fu in open hand (you can make 1-20 hand with that setting)	fu_for_open_pinfu	True
Disable or enable pinfu tsumo	fu_for_pinfu_tsumo	False
Counting renhou as 5 han or yakuman	renhou_as_yakuman	False
Disable or enable Daisharin yakuman	has_daisharin	False
Disable or enable Daisharin in other suits (Daisuurin, Daichikurin)	has_daisharin_other_suits	False
Disable or enable yakuman for dealing into open hands	has_sashikomi_yakuman	False
Limit yakuman calculation to 6 (maximum score 192000)	limit_to_sextuple_yakuman	True
Disable or enable extra yakuman for all honors 7 pairs	has_daichisei	False
Disable or enable paarenchan without any yaku	paarenchan_needs_yaku	True

The code was validated on tenhou.net phoenix replays in total on 11,120,125 hands.

So, we can say that our hand calculator works the same way that tenhou.net hand calculation.

How to use

You can find more examples here: https://github.com/MahjongRepository/mahjong/blob/1x_version/doc/examples.py

Let's calculate how much will cost this hand:

Tanyao hand by ron

from mahjong.hand_calculating.hand import HandCalculator
from mahjong.tile import TilesConverter
from mahjong.hand_calculating.hand_config import HandConfig
from mahjong.meld import Meld

calculator = HandCalculator()

# we had to use all 14 tiles in that array
tiles = TilesConverter.string_to_136_array(man='22444', pin='333567', sou='444')
win_tile = TilesConverter.string_to_136_array(sou='4')[0]

result = calculator.estimate_hand_value(tiles, win_tile)

print(result.han, result.fu)
print(result.cost['main'])
print(result.yaku)
for fu_item in result.fu_details:
    print(fu_item)

Output:

1 40
1300
[Tanyao]
{'fu': 30, 'reason': 'base'}
{'fu': 4, 'reason': 'closed_pon'}
{'fu': 4, 'reason': 'closed_pon'}
{'fu': 2, 'reason': 'open_pon'}

How about tsumo?

result = calculator.estimate_hand_value(tiles, win_tile, config=HandConfig(is_tsumo=True))

print(result.han, result.fu)
print(result.cost['main'], result.cost['additional'])
print(result.yaku)
for fu_item in result.fu_details:
    print(fu_item)

Output:

4 40
4000 2000
[Menzen Tsumo, Tanyao, San Ankou]
{'fu': 20, 'reason': 'base'}
{'fu': 4, 'reason': 'closed_pon'}
{'fu': 4, 'reason': 'closed_pon'}
{'fu': 4, 'reason': 'closed_pon'}
{'fu': 2, 'reason': 'tsumo'}

What if we add open set?

melds = [Meld(meld_type=Meld.PON, tiles=TilesConverter.string_to_136_array(man='444'))]

result = calculator.estimate_hand_value(tiles, win_tile, melds=melds, config=HandConfig(options=OptionalRules(has_open_tanyao=True)))

print(result.han, result.fu)
print(result.cost['main'])
print(result.yaku)
for fu_item in result.fu_details:
    print(fu_item)

Output:

1 30
1000
[Tanyao]
{'fu': 20, 'reason': 'base'}
{'fu': 4, 'reason': 'closed_pon'}
{'fu': 2, 'reason': 'open_pon'}
{'fu': 2, 'reason': 'open_pon'}

Shanten calculation

from mahjong.shanten import Shanten

shanten = Shanten()
tiles = TilesConverter.string_to_34_array(man='13569', pin='123459', sou='443')
result = shanten.calculate_shanten(tiles)

print(result)

Aotenjou scoring rules

tiles = self.TilesConverter.string_to_136_array(honors='11133555666777')
win_tile = self.TilesConverter.string_to_136_array(honors='3')[0]

melds = [
    Meld(meld_type=Meld.KAN, tiles=TilesConverter.string_to_136_array(honors='1111'), opened=False),
    Meld(meld_type=Meld.KAN, tiles=TilesConverter.string_to_136_array(honors='5555'), opened=False),
    Meld(meld_type=Meld.KAN, tiles=TilesConverter.string_to_136_array(honors='6666'), opened=False),
    Meld(meld_type=Meld.KAN, tiles=TilesConverter.string_to_136_array(honors='7777'), opened=False),
]

result = hand.estimate_hand_value(tiles, win_tile, melds=melds, dora_indicators=TilesConverter.string_to_136_array(honors='44447777'),
    scores_calculator_factory=Aotenjou, config=HandConfig(is_riichi=True, is_tsumo=True, is_ippatsu=True, is_haitei=True, player_wind=EAST, round_wind=EAST))

print(result.han, result.fu)
print(result.cost['main'])
print(result.yaku)
for fu_item in result.fu_details:
    print(fu_item)

Output:

95 160
50706024009129176059868128215100
[Menzen Tsumo, Riichi, Ippatsu, Haitei Raoyue, Yakuhai (wind of place), Yakuhai (wind of round), Daisangen, Suu kantsu, Tsuu iisou, Suu ankou tanki, Dora 24]
{'fu': 32, 'reason': 'closed_terminal_kan'}
{'fu': 32, 'reason': 'closed_terminal_kan'}
{'fu': 32, 'reason': 'closed_terminal_kan'}
{'fu': 32, 'reason': 'closed_terminal_kan'}
{'fu': 20, 'reason': 'base'}
{'fu': 2, 'reason': 'pair_wait'}
{'fu': 2, 'reason': 'tsumo'}