| |
| """Dataset loader for ChessBenchmate Aggregated dataset.""" |
|
|
| import msgpack |
| from pathlib import Path |
| from typing import Iterator, Dict, Any |
|
|
|
|
| def stream_positions(data_dir: str, shard_range: tuple = None) -> Iterator[Dict[str, Any]]: |
| """Stream positions from all shards. |
| |
| Args: |
| data_dir: Directory containing the .msgpack files |
| shard_range: Optional (start, end) tuple to limit shards |
| |
| Yields: |
| Dict with 'fen' and 'moves' keys |
| """ |
| data_path = Path(data_dir) |
| shard_files = sorted(data_path.glob('train-*.msgpack')) |
|
|
| if shard_range: |
| start, end = shard_range |
| shard_files = shard_files[start:end] |
|
|
| for shard_file in shard_files: |
| with open(shard_file, 'rb') as f: |
| unpacker = msgpack.Unpacker(f, raw=False) |
| for record in unpacker: |
| yield record |
|
|
|
|
| def count_positions(data_dir: str) -> tuple: |
| """Count total positions and moves in the dataset. |
| |
| Returns: |
| Tuple of (num_positions, num_moves) |
| """ |
| total_positions = 0 |
| total_moves = 0 |
|
|
| for record in stream_positions(data_dir): |
| total_positions += 1 |
| total_moves += len(record['moves']) |
|
|
| return total_positions, total_moves |
|
|
|
|
| if __name__ == '__main__': |
| import sys |
|
|
| if len(sys.argv) < 2: |
| print("Usage: python dataset.py <data_dir>") |
| sys.exit(1) |
|
|
| data_dir = sys.argv[1] |
|
|
| print(f"Sampling positions from {data_dir}...") |
| for i, record in enumerate(stream_positions(data_dir)): |
| print(f"\nPosition {i+1}:") |
| print(f" FEN: {record['fen']}") |
| print(f" Moves: {len(record['moves'])}") |
| for move, eval in list(record['moves'].items())[:3]: |
| print(f" {move}: win_prob={eval['win_prob']:.3f}, mate={eval['mate']}") |
| if i >= 4: |
| break |
|
|
