shakmaty-syzygy

A Rust library to probe Syzygy endgame tablebases, based on shakmaty.

Syzygy tables allow optimal play under the 50-move rule. Tables are available for positions with up to 7 pieces.

Example: Usage

```rust use shakmaty::{CastlingMode, Chess, fen::Fen}; use shakmaty_syzygy::{Tablebase, MaybeRounded, Wdl, Dtz, Syzygy};

let mut tables = Tablebase::new(); tables.add_directory("tables/chess")?;

let pos: Chess = "8/8/8/8/B7/N7/K2k4/8 b - - 0 1" .parse::()? .into_position(CastlingMode::Standard)?;

let wdl = tables.probewdlafterzeroing(&pos)?; asserteq!(wdl, Wdl::Loss);

let dtz = tables.probe_dtz(&pos)?; assert!(matches!(dtz, MaybeRounded::Rounded(Dtz(-59)))); ```

Example: Command line tool

A command line tool similar to Fathom:

``` $ cargo run --example fathom -- --path tables/chess -- "3qk3/8/8/8/8/8/8/4K3 w - - 0 1" [Event "KvKQ"] [Site ""] [Date "????.??.??"] [Round "-"] [White "Syzygy"] [Black "Syzygy"] [Result "0-1"] [FEN "3qk3/8/8/8/8/8/8/4K3 w - - 0 1"] [Annotator "shakmaty-syzygy"] [DTZ "-16 or -17"]

{ KvKQ with DTZ -16 or -17 } 1. Ke2 Kd7 2. Kd1 Ke6+ 3. Kc1 Qd3 4. Kb2 Qd2+ 5. Ka1 Kd5 6. Kb1 Kc4 7. Ka1 Kb3 8. Kb1 Qd1# { Checkmate } 0-1 ```

Documentation

Read the documentation

Acknowledgement

Thanks to Ronald de Man for his Syzygy tablebases. The probing code is closely based on his implementation for Stockfish.

License

shakmaty-syzygy is licensed under the GPL-3.0 (or any later version at your option). See the COPYING file for the full license text.