@cloviz/eq-mc

WebAssembly poker equity calculator for Texas Hold'em.

Install

npm install @cloviz/eq-mc

Usage

import init, {
  calculate_combo_equity,
  calculate_combo_equity_exact,
} from "@cloviz/eq-mc"

await init()

const approximate = calculate_combo_equity("AsAh,KsKh", "", "", 100000)
const exact = calculate_combo_equity_exact("AsAh,KsKh", "", "")
const exactWithDeadCards = calculate_combo_equity_exact("AsAh,KsKh", "2c,7d,Ts", "Qc")

console.log({ approximate, exact, exactWithDeadCards })

API

calculate_combo_equity(combos, board, deadCards, trials)

Monte Carlo combo equity.

• combos: comma-separated combos, for example "AsAh,KsKh"
• board: comma-separated board cards, for example "2c,7d,Ts", or ""
• deadCards: comma-separated cards to exclude, for example "Ad,Kc", or ""
• trials: simulation count
• returns comma-separated equities, for example "0.826370,0.173630"

calculate_combo_equity_exact(combos, board, deadCards)

Exact combo equity by exhaustive runout enumeration.

• combos: comma-separated combos
• board: comma-separated board cards, or ""
• deadCards: comma-separated cards to exclude, for example "Ad,Kc", or ""
• returns comma-separated equities

For preflop heads-up exact equity, this API can use an optional packed lookup table loaded with load_preflop_hu_table. Without the table it falls back to the normal exact path.

calculate_range_equity(ranges, board, deadCards, trials)

Monte Carlo range equity.

• ranges: pipe-separated weighted ranges, for example "AsKs:1.0,AsKh:0.5|QhQd:1.0,QhQc:1.0"
• board: comma-separated board cards, or ""
• deadCards: comma-separated cards to exclude, for example "Ad,Kc", or ""
• trials: simulation count
• returns comma-separated equities

load_preflop_hu_table(bytes)

Loads an optional packed preflop heads-up exact equity table.

• bytes: Uint8Array containing the EQPH binary table
• returns true when the table was loaded, false when it was already loaded or the format is invalid

is_preflop_hu_table_loaded()

Returns whether the optional preflop heads-up table is loaded.

Packed Preflop HU Table Format

The table is intentionally not bundled into the npm package. It is meant to be served by applications that need low-latency preflop heads-up exact equity.

• header: 16 bytes
• magic: EQPH
• version: 1
• combo count: 1326
• entries: upper triangle only, excluding identical combo pairs
• entry size: 6 bytes
• entry payload: firstWins and chops as little-endian unsigned 24-bit ints
• total runouts per entry: 1_712_304

The canonical first/second order is the ascending combo-id order. Callers do not need to canonicalize hands before passing them to calculate_combo_equity_exact.