PGNXtract 2025.02.21

PGNBook is now called PGNXtract. The name change is intended to make it clear that this is primarily about filtering PGN files with pgn-extract. The fact that you can also create a Polyglot opening book from the generated PGN files is a nice side effect. When creating an opening book, you have to answer the following questions beforehand (please refer to the readme file for more details):

Remove games by using tag files [y]?
Remove games with setup tags (e.g. Chess960) [y]?
Remove comments, NAGs and variations [y]?
Maximum number of plies (optional):
Additional parameters for pgn-extract (optional):
Remove duplicate games [y]?