Search found 2668 matches

by mcostalba
Wed Aug 30, 2017 12:07 pm
Forum: Computer Chess Club: General Topics
Topic: Stockfish no progress in 2month and half , why ?
Replies: 49
Views: 13202

Re: Stockfish no progress in 2month and half , why ?

Probably the majority of the patches that pass STC are lucky runs these days (this will happen for 1 neutral patch in 20). However most of those lucky runs will be caught by the LTC test. This creates somehow the perception that the STC test is not a good predictor for the LTC test, leading people ...
by mcostalba
Wed Aug 30, 2017 10:11 am
Forum: Computer Chess Club: General Topics
Topic: New version: Demolito 2017-08-26
Replies: 32
Views: 5807

Re: New version: Demolito 2017-08-26

So the only elegant and reliable solution is to use exceptions. That's in C++, at least. Yes, in C++ the solution is to use exceptions. I tried that in the past, at YBWC time, and it didn't worked, maybe now with lazy SMP is easier to implement...maybe a sub-project for some interested SF developer...
by mcostalba
Wed Aug 30, 2017 9:53 am
Forum: Computer Chess Club: General Topics
Topic: Stockfish no progress in 2month and half , why ?
Replies: 49
Views: 13202

Re: Stockfish no progress in 2month and half , why ?

Probably the majority of the patches that pass STC are lucky runs these days (this will happen for 1 neutral patch in 20). However most of those lucky runs will be caught by the LTC test. This creates somehow the perception that the STC test is not a good predictor for the LTC test, leading people ...
by mcostalba
Mon Aug 28, 2017 9:22 am
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

This is a good source for having an understanding on this topic: http://galen.metapath.org/egtb50/ IMO DTM is an obsolete concept today, WDL is enough in real games and in studies the engine will easily analyse an endgame (so with few pieces) up to very high depths in short time, and will work out t...
by mcostalba
Sun Aug 27, 2017 12:11 pm
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

But shouldn't the condition here be: if (wdl <= drawScore) Thanks Joseph, yes you are right. I have rewritten the logic to accomplish following goals: - Full symmety between win and lose positions - Full symmetry between PV and non-PV nodes (it probes also in PV nodes) - Full effice...
by mcostalba
Sat Aug 26, 2017 7:18 am
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

As a reference current version under same conditions did:

Code: Select all

stockfish&#58; Found 145 tablebases
Solving&#58; D&#58;\Documents\chess tests\endgame\Eigenmann Endgame Test.cbh
Maximum time = 15s.

Result&#58; 88 out of 100 = 88.0%. Average time = 1.61s / 18.61
by mcostalba
Sat Aug 26, 2017 6:54 am
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

Here is the result of this test set: https://chessprogramming.wikispaces.com/Eigenmann+Endgame+Test 5-men, 15 sec per position, single core Intel-i5 2.6 Ghz stockfish: Found 145 tablebases Solving: D:\Documents\chess tests\endgame\Eigenmann Endgame Test.cbh Maximum time = 15s. 2. E_E_T 003 - B vs B,...
by mcostalba
Sat Aug 26, 2017 6:23 am
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

As a reference, this is the TB code as of today: // Step 4a. Tablebase probe if (!PvNode && ss->tbCardinality) { int piecesCount = pos.count<ALL_PIECES>(); if ( piecesCount <= ss->tbCardinality && (piecesCount < ss->tbCardinality || depth >= TB::ProbeDepth) && !pos.can_castle(AN...
by mcostalba
Sat Aug 26, 2017 6:19 am
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

Well, Bound Exact is only correct for draws, the result will never be greater than or less than a draw. But in the case of a TB win, that DTZ result implies mate eventually. To me, it certainly makes sense to treat a mate in X number of moves as greater value than mate eventually (and indeed this i...
by mcostalba
Fri Aug 25, 2017 8:05 pm
Forum: Computer Chess Club: General Topics
Topic: Natural TB
Replies: 330
Views: 66459

Re: Natural TB (take 2)

I still use the rule50 count, I just did not post the entirety of the code (only the relevant changes). Here is the complete code block: <cut> tte->save(posKey, value_to_tt(value, ss->ply), v > drawScore ? BOUND_LOWER : v < -drawScore ? BOUND_UPPER : BOUND_EXACT, depth, MOVE_NONE, VALUE...