Search found 2878 matches

by Evert
Thu Jun 21, 2018 11:37 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about the value of fairy pieces
Replies: 10
Views: 316

Re: about the value of fairy pieces

I think it's important to make a distinction between opening and end game values. I can imagine Crab/Barc beating a Knight in the end game simply because the Knight cannot easily defend both flanks. I also believe that the value difference between Q and B/R goes down in the end game. What would be a...
by Evert
Thu Jun 21, 2018 5:00 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about the value of fairy pieces
Replies: 10
Views: 316

Re: about the value of fairy pieces

But suppose you replace Pawns by (promoting) Ferzes (or allow FIDE Pawns to capture backwards, fmWcF). These make chains that are self-protecting, and can only be damaged at the expense of the first attacker. So it would be more helpful to have two pieces, one of which less valuable than a pair of ...
by Evert
Wed Jun 20, 2018 9:14 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about the value of fairy pieces
Replies: 10
Views: 316

Re: about the value of fairy pieces

Seems contrived on a normal board, normal rules and an otherwise balanced army. It would imply that B and C are due some sort of synergy bonus (generalised pair bonus) that is larger when the pieces are further apart (or at least, not on the same square). The effect HGM mentions is of course also im...
by Evert
Tue Jun 12, 2018 5:16 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: whether or not a piece has moved and how many times
Replies: 11
Views: 679

Re: whether or not a piece has moved and how many times

Curious about how others have implemented calculation of how many times each piece has moved since the beginning of the game. The concern is when a piece has been captured in a make move and then uncaptured and updating the array. How did you solve this? I'd do it the same way I handle the 50-move ...
by Evert
Tue Jun 05, 2018 8:46 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Bitboard for a non-chess game
Replies: 4
Views: 606

Re: Bitboard for a non-chess game

You should be able to use the same logic as for pawn duo's and hanging pawns (there's a breakdown of the logic on CPW). Essentially you have to find squares that border exactly one empty square, which can be done by testing for squares that have an empty square to the West (say), but not in any of t...
by Evert
Thu May 31, 2018 12:30 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Move ordering based on stored values of child nodes
Replies: 4
Views: 435

Re: Move ordering based on stored values of child nodes

With current move ordering heuristics, you get a cut-off from the first three moves in 95-99% of cases. That's the statistic you have to beat. Any effort spent on move ordering in ALL-nodes is wasted. Any effort in improving move ordering in a CUT-node is wasted in 95-99% of cases, so whatever you p...
by Evert
Tue May 22, 2018 8:52 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: 7-men Syzygy attempt
Replies: 428
Views: 45271

Re: 7-men Syzygy attempt

Ok, so I'm sure I've asked this before, but I don't remember the explanation and I can't find it using the search. Assuming I have N-piece DTM and DTZ50 tables. Can't I get DTM50 optimal play (not value) by first reducing the move list to those moves that preserve the win (according to DTZ50), and ...
by Evert
Tue May 22, 2018 6:11 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: 7-men Syzygy attempt
Replies: 428
Views: 45271

Re: 7-men Syzygy attempt

DTM50 conceptually stores a distance-to-mate value for each pair (position, rule50_counter). So that is 100x as much raw data as for DTM. The sequence of values for a particular position is far from random, but it is not immediately obvious how to find an efficient encoding that fits into a good co...
by Evert
Fri May 18, 2018 5:56 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Issue with self play testing
Replies: 5
Views: 546

Re: Issue with self play testing

Upon reflection, I see that the Elo gain is possibly 2x that: the old Ares never made such attacks and thus the ability to defend against them went untested and unmeasured. Yes, and that's why the gain is typically less than it is in self-play: the other opponent may not have been so blind, so you ...
by Evert
Fri May 11, 2018 6:42 am
Forum: Computer Chess Club: General Topics
Topic: Regarding Talkchess update and features
Replies: 33
Views: 2327

Re: Regarding Talkchess update and features

Can you activate the option to automatically open new links in new tabs though? Currently if you forget to click with the middle button or with ctrl, it's quite annoying. Urgh, please don't! Nothing pisses me off more* than a website deciding for me that I want to open a link in a new tab. If I wan...