Track the number of mates from matetrack.epd of Joost VandeVondele' matetrack
that are scored correctly on chessdb.cn (cdb), the largest online database of chess positions and openings.
The files matetrack_cdbeval.epd
and matetrack_cdbpv.epd are created weekly with
the help of the scripts fens2cdb.py and cdbbulkpv.py from cdblib, respectively, and the obtained mate statistics are written to cdbmatetrack.csv.
The file matetrack.epd contains 6554 mate problems, ranging from mate in 1 (#1) to #126 for positions with between 4 and 32 pieces. Moreover:
- 865 positions have 7 pieces or fewer.
- Of these 7men positions, 9 are not scored by cdb because they allow castling.
As cdb currently does not store mate scores for 7men EGTB positions, the theoretically maximal number of (best) mates it can find within this test suite is 5691. Note that this is an upper bound. The currently achievable number of (best) mates may in fact be lower, and relies on the cdb worker's ability to resolve mating lines that end in 7men EGTB positions. Recent SF versions find about 3600 mates (and 2500 best mates) with 1M nodes per position, see matetrack.
The two files matetrack_cdbmates.epd and matetrack_cdbnonmates.epd contain the positions for which cdb reports a mate and a non-mate score, respectively, where the latter file excludes positions with 7 pieces or fewer. Both files are sorted: matetrack_cdbmates.epd by difference in mate score between cdb's mate and the best mate, and matetrack_cdbnonmates.epd by absolute value of the cdb eval.
