Training data generation

Training data generation using Fairy-Stockfish

Training data generator: https://github.com/ianfab/Fairy-Stockfish/tree/tools

Example

uci
setoption name Use NNUE value false
setoption name Threads value 8
setoption name Hash value 2048
setoption name UCI_Variant value extinction
isready
generate_training_data depth 2 count 10000000 random_multi_pv 4 random_multi_pv_diff 100 random_move_count 8 random_move_max_ply 20 write_min_ply 5 eval_limit 10000 set_recommended_uci_options data_format bin output_file_name extinction.bin
quit

If you want to use an existing NNUE network for training data generation, you need to change Use NNUE to pure and set the EvalFile, e.g., something like

setoption name Use NNUE value pure
setoption name EvalFile value somevariant-1234567890ab.nnue

Settings

Since only bin format is supported, you need to specify data_format bin.
For variants with a low branching factor like losers/antichess, it is recommended to increase the random_multi_pv_diff in order to increase the variety of positions.

Generating data from old HalfKP networks

If you want to use an old HalfKP NNUE network to start generating training data, you can use the old generator code at https://github.com/ianfab/variant-nnue. However, since the training data format was changed in the meantime, this will only work with older versions of the trainer, the latest compatible version should be https://github.com/ianfab/variant-nnue-pytorch/tree/91c302941acb131fbabb441dd6ced992ec04dfcb. Also the syntax for the training data generation command looks slightly different. An example is:

gensfen depth 2 loop 100000000 random_multi_pv 4 random_multi_pv_diff 100 random_move_count 8 random_move_maxply 20 write_minply 5 write_maxply 200 eval_limit 10000 set_recommended_uci_options sfen_format bin output_file_name extinction.bin