Mahjong hands calculation

## Project description

For now only Python 3.5+ is supported.

## Riichi mahjong hands calculation

This library can calculate hand cost (han, fu with details, yaku and scores) for riichi mahjong (japanese version).

It supports features like:

• Disable or enable aka dora in the hand
• Disable or enable open tanyao yaku
• Disable or enable double yakuman (like suuanko tanki)
• Settings for different kazoe yakuman calculation (it kan be an yakuman or a sanbaiman)
• Support kiriage mangan
• Allow to disable additional +2 fu in open hand (you can make 1-20 hand with that setting)

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

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

Right now it supports only japanese version (riichi mahjong). MCR (chinese version) is in plans.

Project repository: https://github.com/MahjongRepository/mahjong

### How to install

```pip install mahjong
```

### How to use

You can find more examples here: https://github.com/MahjongRepository/mahjong/blob/master/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'}
```

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

print(result.han, result.fu)
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(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)
```

## Releases History

### 1.1.2 (2017-10-14)

• Add settings for different kazoe yakuman calculation (it kan be an yakuman or a sanbaiman)
• Support up to sextuple yakuman scores
• Support kiriage mangan
• Allow to disable +2 fu in open hand
• Allow to disable tsumo pinfu (add 2 additional fu for hand like that)

### 1.1.1 (2017-10-07)

• Fix a bug with not correct agari state determination and closed kan in the hand

### 1.1.0 (2017-10-07)

Breaking changes:

• Interface of hand calculator was changed. New interface will allow to easy support different game rules

• Refactor hand divider. Allow to pass melds objects instead of arrays
• Add file with usage examples
• Minor project refactoring

### 1.0.5 (2017-09-25)

• Improve installation script

### 1.0.4 (2017-09-25)

Bug fixes:

• Fix refactoring regressions with kan sets and dora calculations
• Fix regression with sankantsusuukantsu and called chankan
• Closed kan can’t be used in chuuren poutou
• Fix yaku ids (some of them had incorrect numbers)

Features:

• Allow to disable double yakuman (like suuanko tanki)
• Remove float calculations from scores and fu