Uri Blass wrote: ↑Thu Aug 15, 2019 7:41 am
Note that I do not know about a single engine that can detect when a draw is a draw(that means no possible mate for the opponent)
stupid Stockfish even cannot evaluate obvious draw chess positions by the chess rules as 0.00 and I do not believe there is a chess server that is going to give you a draw if you lose on time in one of the following positions
[d]4k3/1p1p1p1p/pPpPpPpP/P1P1P1P1/8/8/8/2B1K3 w - - 1 1
Quickly testing this position on my phone, it seems like Stockfish quickly reaches a (displayed) depth of 98/99 plies but then stalls.
Running it on my Raspberry Pi right now, I'm wondering how many nodes it will take before it realizes the 50 move draw can't be avoided.
After using a calculator and letting my pi run for 48 hours I don't think it will ever find it.
It can't see that it has no way of winning and calculating every possible move (At least 7^25) would take way too long.
Uri Blass wrote: ↑Thu Aug 15, 2019 7:41 am
Note that I do not know about a single engine that can detect when a draw is a draw(that means no possible mate for the opponent)
stupid Stockfish even cannot evaluate obvious draw chess positions by the chess rules as 0.00 and I do not believe there is a chess server that is going to give you a draw if you lose on time in one of the following positions
[d]4k3/1p1p1p1p/pPpPpPpP/P1P1P1P1/8/8/8/2B1K3 w - - 1 1
Quickly testing this position on my phone, it seems like Stockfish quickly reaches a (displayed) depth of 98/99 plies but then stalls.
Running it on my Raspberry Pi right now, I'm wondering how many nodes it will take before it realizes the 50 move draw can't be avoided.
Minic sees the draw in 40ms as expected at depth 99
vb4 wrote: ↑Thu Aug 15, 2019 8:28 am
Bob you are right the position is illegal my mistake. The point was unless a position is 100% certain that its a draw then just because black only has a knight doesn't foot the bill. To me only 2 kings and a bishop or 2 kings and a knight I think are the only 2 scenarios guaranteed a draw. Uri only these 2 cases I believe can the server know for sure its a draw. One more diagram of another case.
[d]K2k4/P7/4n3/8/RP1P4/8/8/8 b - -
Now if black king goes to c8 what can white do to prevent black knight to c7 mate? This is what I am having problems with.
As I said, the rules are far from perfect. I don't know what a server would do with that knight mate you posted above. It would accept the mate, obviously, but if your opponent's flag fell first? I'd bet it would be a draw.
The last section about article 10 seems strange: If I understand correctly, if you are playing a sudden death time control and have 7 minutes left, your draw claim will be rejected. But then if you wait 5 minutes and repeat the claim, it will be accepted?
