Search found 433 matches

by Aleks Peshkov
Wed Nov 28, 2018 9:10 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: How to incrementally update attack tables?
Replies: 5
Views: 1207

Re: How to incrementally update attack tables?

Board representation for incremental attack tables should be build from scratch.
It is not a efficient idea to add attacks as extra weight to well-known representations.
by Aleks Peshkov
Fri Nov 02, 2018 4:27 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Blocking input
Replies: 3
Views: 733

Re: Blocking input

You need to do std::flush() after printing each info string.
by Aleks Peshkov
Thu Aug 16, 2018 11:02 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Attacks From table
Replies: 12
Views: 3520

Re: Attacks From table

This representaion is as fast as the fastest perft known engines. My principal chess representation consists of 16-byte vector for each 16 chess piece from each side. attackMap is array of Ranks of BitRank vectors for each piece; BitRank: byte of 8 squares per rank (1/8 of bitboard); PieceId: index ...
by Aleks Peshkov
Tue Aug 07, 2018 8:59 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: need to update my knowledge
Replies: 14
Views: 1803

Re: need to update my knowledge

Stroustrup's "The C++ Programming Language" is must read for practical experience. I personally read some old Effective C++ books and dislike them all. Agile is all about Team Project Management not about individual programming skills. "Clean Code" is good reading for programmer but it is not a tuto...
by Aleks Peshkov
Wed Mar 21, 2018 8:42 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: trick question
Replies: 25
Views: 5722

Re: trick question

The trick is to use second counter. unsigned long nodes; unsigned long nodesLimit; //search limit enum : unsigned { TickLimit = 5000 }; // ~1 msec unsigned nodesQuota; //number of remaining nodes before slow checking for terminate // the current exact number of nodes node_count_t getNodes&...
by Aleks Peshkov
Mon Mar 05, 2018 10:18 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: [Discussion] - Measuring move ordering
Replies: 14
Views: 4077

Re: [Discussion] - Measuring move ordering

There is a true metric: ratio of nodes pruned relative to full minimax tree.
by Aleks Peshkov
Thu Mar 01, 2018 8:47 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Some opening book design questions
Replies: 39
Views: 10567

Re: Some opening book design questions

jdart wrote:Color-flipped positions *can* occur in chess, but I would be surprised if they were frequent enough to make this optimization a significant win.

--Jon
It is easy to make color-independent but side-to-move dependent board representation. So all hashing and evaluation are transparently symmetrical.
by Aleks Peshkov
Fri Jan 26, 2018 7:27 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Alpha-Beta as a rollouts algorithm
Replies: 15
Views: 5669

Re: Alpha-Beta as a rollouts algorithm

Please can you explain what is rollout algorithm in simple words?
by Aleks Peshkov
Tue Aug 29, 2017 12:06 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question on Null Move Pruning
Replies: 19
Views: 3366

Re: Question on Null Move Pruning

Null move heuristic should not be done on PV-nodes. To my limited understanding all non-PV nodes in PVS are searched with null-window.
by Aleks Peshkov
Mon Apr 24, 2017 4:02 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Hash move and move ordering
Replies: 2
Views: 957

Re: Hash move and move ordering

It is possible to store lower- and upper- bound score with their respective depths (exact score is both upper and lower bounds) of the same position, but the hash move should be only one (or sometimes none).