albertajuelo / pokerhand-eval

Poker Texas Hold'em Hand Evaluator using pure Lua

PokerHand-eval

Poker Texas Hold'em Hand Evaluator using pure Lua.

Contents

• Overview
• Origin
• Requirements
• Basic Usage
• Documentation
• Development
• References

Overview

This is a pure Lua library to calculate the rank of the best [Texas Holdem] hand out of 5, 6, or 7 cards. It does not run the board for you, or calculate winning percentage, EV, or anything like that. But if you give it two hands and the same board, you will be able to tell which hand wins.

Also there is a two-card ranking/percentile algorithm (Credit to Zach Wissner-Gross).

This is a Lua port from the python library.

Origin

This repository is based on Ivan Ribeiro (@irr) work: https://github.com/irr/lua-pokerhand-eval

Requirements

Lua version required: 5.1 or 5.2.

Basic Usage

If using LuaRocks:

luarocks install pokerhand-eval

Otherwise, download https://github.com/AlberTajuelo/pokerhand-eval/zipball/master.

Alternately, if using GIT:

git clone git://github.com/AlberTajuelo/pokerhand-eval.git

cd pokerhand-eval 

luarocks make

Calculate Hand winning percentile without board cards:

    card = require "holdem.card"
    lookup = require "holdem.lookup"
    analysis = require "holdem.analysis"

    hand = { Card.new(2, 1), Card.new(2, 2) }
    board = {}
    rank, percentile = analysis.evaluate(hand, board)
    print(rank, percentile)
    -- Output: nil	0.52337858220211
    -- For 2 cards, rank will be nil and you must use percentile

Calculate hand winning percentile with three board cards:

    card = require "holdem.card"
    lookup = require "holdem.lookup"
    analysis = require "holdem.analysis"

    hand = { Card.new(2, 1), Card.new(2, 2) }
    board = { Card.new(10, 2), Card.new(14, 2), Card.new(13, 2), Card.new(7, 2) }
    rank, percentile = analysis.evaluate(hand, board)
    print(rank, percentile)
    -- Output: 420  0.6792270531401
    -- ps: less rank is better

Documentation

Card Rank

This table represents given a card rank what index is assigned. Rank is 2-14 representing 2-A (Ace).

Card Rank	Index	Symbol
2	2	2
3	3	3
4	4	4
5	5	5
6	6	6
7	7	7
8	8	8
9	9	9
10	10	T
Jack	11	J
Queen	12	Q
King	13	K
Ace	14	A

Card Suit

This table represents given a card suit what index is assigned. Suit is 1-4 representing in given order Spades, Hearts, Diamonds and Clubs.

Card Suit	Index	Symbol
Spades (♠)	1	S
Hearts (♥)	2	H
Diamonds (♦)	3	D
Clubs (♣)	4	C

Card Constructor

The Card constructor accepts two arguments, rank, and suit.

    card = require "holdem.card"

    aceOfSpades = card.Card(14, 1)
    twoOfDiamonds = card.Card(2, 3)

    -- or

    aceOfSpades = card.Card("AS")
    twoOfDiamonds = card.Card("2D")

Development

PokerHand-eval is currently in development.

WARNING: Not all corner cases have been tested and documented.

References

The algorithm for 5 cards is just a port of this algorithm.

Six and seven card evaluators using a very similar card representation and applying some of the same ideas with prime numbers. The idea was to strike a balance between lookup table size and speed.

You can search for more info using following references:

• Texas Holdem
• BitOp-lua
• underscore-dot-lua