I use Arena to open the pgn and looked for the game where Weini lost the quickest

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I use Arena to open the pgn and looked for the game where Weini lost the quickest
I think Xiphos and Vajolet is doing both.Didn't check others.Edsel Apostol wrote: ↑Wed Sep 12, 2018 7:12 pmI think most strong engines doesn't check for && score < beta anymore.
Usually you don't store a bestmove in the TT if score is equal or below alpha.
Code: Select all
!fromPV || ttt.t_type == Transposition::tt_exact
Code: Select all
!fromPV ||
(ttt.t_type == Transposition::tt_exact
&& ttt.score > alpha
&& ttt.score < beta) ||
(ttt.t_type == Transposition::tt_alpha
&& ttt.score <= alpha) ||
(ttt.t_type == Transposition::tt_beta
&& ttt.score >= beta) ) )
I think you are messing around a bit with TT.xr_a_y wrote: ↑Fri Sep 14, 2018 5:56 pmMoreover, I used to not use the TT move directly (i.e. return a score immediatly) if it leads to a draw (I was afraid of false draw score due to 3 reps but now I use only 1 rep so probably no need to worry anymore). I now use the TT move (under the previous conditions) also if it leads to a draw.Code: Select all
!fromPV || (ttt.t_type == Transposition::tt_exact && ttt.score > alpha && ttt.score < beta) || (ttt.t_type == Transposition::tt_alpha && ttt.score <= alpha) || (ttt.t_type == Transposition::tt_beta && ttt.score >= beta) ) )
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THashEntry entry;
if (Hash.hash_get(Current->key, &entry)){
if (TO_MOVE(entry.move) != NULL_MOVE && is_pseudolegal(TO_MOVE(entry.move))){
trans_move = TO_MOVE(entry.move);
pv_copy( trans_move );
}
entry.eval = hash_value_get(entry.eval, root_distance() );
if (entry.ok_to_prune(depth, alpha, beta)){
return entry.eval;
}
}
Code: Select all
bool THashEntry::ok_to_prune(int depth, int alpha, int beta){
return (
(isMate(this->eval) && this->type == typeExact)
|| (
(this->depth >= depth) &&
(
(this->type == typeExact) ||
(this->type == typeAlpha && this->eval <= alpha) ||
(this->type == typeBeta && this->eval >= beta)
)
)
);
}
Sander is quite right. You have at least a serious repetition bug!sandermvdb wrote: ↑Wed Sep 12, 2018 8:15 pmI just downloaded the games Weini 0.0.20 played in the CCRL 40/4. This is the game it has lost in the least number of moves:
https://lichess.org/aoEmr338
It looks like a 3-fold repetition bug where it just throws away its queen and therefore loses the match.
Greg Strong@ovyron wrote: http://talkchess.com/forum3/viewtopic.p ... 86#p752386
Thanks for your inputs. So you suggest to use the TT move and return a score with it as soon as it is an exact score, even at a PV node ?asanjuan wrote: ↑Fri Sep 28, 2018 7:36 amCode: Select all
(this->type == typeExact) || (this->type == typeAlpha && this->eval <= alpha) || (this->type == typeBeta && this->eval >= beta)
119.g6?! is not optimal but still a draw. The decisive error is 120.Ke2? where the only move that holds the draw is 120.Kc3! Therefore another possible explanation of the symptom would be that the search depth was not sufficient to see that Kc3 draws but Ke2 loses. The score 0.00 calculated for 120.Ke2, compared to -2.99 after the next move, makes this quite likely for me. I do not see a clear connection to the repetition topic in this case.Guenther wrote: ↑Fri Sep 28, 2018 10:12 amExample1:
Asymptotes eval also is wrong for a long while and Weini showing around -0.84 has a comfortable
positionally draw and could have just sat with its K around the Black passer on e3 awaiting a 3 time rep
or a 50 moves draw as Black can do nothing.
Instead it suddenly created a decisive weakness with 119.g6??
I could understand it if would show a positive score and attempts to win.
Hi Sven, I wrote this because 119.g6 was played with negative score (-0.72), why should one move a pawn, when the the 50 moves counterSven wrote: ↑Sat Sep 29, 2018 3:39 pm119.g6?! is not optimal but still a draw. The decisive error is 120.Ke2? where the only move that holds the draw is 120.Kc3! Therefore another possible explanation of the symptom would be that the search depth was not sufficient to see that Kc3 draws but Ke2 loses. The score 0.00 calculated for 120.Ke2, compared to -2.99 after the next move, makes this quite likely for me. I do not see a clear connection to the repetition topic in this case.Guenther wrote: ↑Fri Sep 28, 2018 10:12 amExample1:
Asymptotes eval also is wrong for a long while and Weini showing around -0.84 has a comfortable
positionally draw and could have just sat with its K around the Black passer on e3 awaiting a 3 time rep
or a 50 moves draw as Black can do nothing.
Instead it suddenly created a decisive weakness with 119.g6??
I could understand it if would show a positive score and attempts to win.
Greg Strong@ovyron wrote: http://talkchess.com/forum3/viewtopic.p ... 86#p752386
Don't forget the depth condition in order to return a TT cutoff.xr_a_y wrote: ↑Fri Sep 28, 2018 3:07 pmThanks for your inputs. So you suggest to use the TT move and return a score with it as soon as it is an exact score, even at a PV node ?asanjuan wrote: ↑Fri Sep 28, 2018 7:36 amCode: Select all
(this->type == typeExact) || (this->type == typeAlpha && this->eval <= alpha) || (this->type == typeBeta && this->eval >= beta)