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Interesting position from Jouni Uski
Posted: Wed May 02, 2007 8:14 pm
by GeoffW
Hi
[D]5K2/8/2qk4/2nPp3/3r4/6B1/B7/3R4 w - e6 0 1
Thought it was worth reposting this in programmers forum as this is a very interesting position for showing up engine bugs with FEN reading, ep captures and checks. This is a mate in 1 position due to the ep capture.
I was really surprised to find how many well known engines cant see the mate in 1
Ruffian, Crafty, Frenzee, Pharoan, Baron, Aice, Colossus, Homer2 to name but a few.
Happy bug hunting
Geoff
Re: Interesting position from Jouni Uski
Posted: Wed May 02, 2007 8:43 pm
by NKOTB
the old e.p. !! Delightful
Re: Interesting position from Jouni Uski
Posted: Wed May 02, 2007 8:59 pm
by Alessandro Scotti
No problem at all for Kiwi or Hamsters... this must be the first bug I do not have!
Re: Interesting position from Jouni Uski
Posted: Wed May 02, 2007 9:34 pm
by Zlaire
No problem for Mediocre either.
However are you sure it is not an interface problem? Meaning are you sure the actual position is passed to the engine? I know Arena has had problems with fen strings containing en passant squares (in the latest beta it can't input fen strings at all though
).
Re: Interesting position from Jouni Uski
Posted: Wed May 02, 2007 11:36 pm
by GeoffW
Hi Jonatan
Yes I am sure it is not an interface problem provided you use Arena version 1.1. Do not use the more recent betas as they have problems with fen handling.
For example as Alessandro pointed out, Hamsters and Kiwi work fine. I know, I tried them both with Arena, they escaped my hit list above
Geoff
Re: Interesting position from Jouni Uski
Posted: Fri May 04, 2007 5:09 pm
by bob
Crafty sees this just fine:
Code: Select all
White(1): move
time surplus 0.00 time limit 22.50 (+0.00) (3:30)
depth time score variation (1)
1 0.00 -2.24 1. Rxd4
1 0.00 Mate 1. dxe6#
1-> 0.00 Mate 1. dxe6#
2 0.00 Mate 1. dxe6#
2-> 0.00 Mate 1. dxe6#
3 0.00 Mate 1. dxe6#
3-> 0.00 Mate 1. dxe6#
4 0.00 Mate 1. dxe6#
4-> 0.00 Mate 1. dxe6#
time=0.00 mat=-6 n=790 fh=100% nps=1.0M
ext-> check=18 1rep=0 mate=0 pp=0 reduct=121/0
predicted=0 evals=424 50move=0 EGTBprobes=0 hits=0
SMP-> splits=0 aborts=0 data=0/128 elap=0.00
Perhaps this is more of an operator error than a bug in multiple programs?
Re: Interesting position from Jouni Uski
Posted: Fri May 04, 2007 5:11 pm
by bob
you need to figure out why Crafty failed the test, when it works perfectly for any version I tried... There is definitely an interface or operator issue involved here.
Re: Interesting position from Jouni Uski
Posted: Fri May 04, 2007 6:04 pm
by Alessandro Scotti
bob wrote:you need to figure out why Crafty failed the test, when it works perfectly for any version I tried... There is definitely an interface or operator issue involved here.
At the time I did a quick test with Crafty on Mac OS X (it was version 19.13 IIRC, downloaded with Fink), just open a terminal, run crafty, setboard and analyze, and it failed to find the move.
What are the commands I have to give to obtain the panel you posted? After so much time with UCI/custom interface I forgot how to use XBoard protocol manually!
Re: Interesting position from Jouni Uski
Posted: Fri May 04, 2007 9:44 pm
by bob
Alessandro Scotti wrote:bob wrote:you need to figure out why Crafty failed the test, when it works perfectly for any version I tried... There is definitely an interface or operator issue involved here.
At the time I did a quick test with Crafty on Mac OS X (it was version 19.13 IIRC, downloaded with Fink), just open a terminal, run crafty, setboard and analyze, and it failed to find the move.
What are the commands I have to give to obtain the panel you posted? After so much time with UCI/custom interface I forgot how to use XBoard protocol manually!
No idea what is wrong there. Here is 19.13 on my office box:
Code: Select all
crafty% crafty
unable to open book file [./book.bin].
book is disabled
unable to open book file [./books.bin].
EGTB access enabled
using tbpath=./TB
0 piece tablebase files found
Crafty v19.13 (1 cpus)
White(1): 5K2/8/2qk4/2nPp3/3r4/6B1/B7/3R4 w - e6 0 1
White(1): noise 0
noise level set to 0.
White(1): move
clearing hash tables
time surplus 0.00 time limit 30.00 (3:30)
depth time score variation (1)
1 0.00 -1.16 1. Rxd4
1 0.00 Mate 1. dxe6#
1-> 0.00 Mate 1. dxe6#
2 0.00 Mate 1. dxe6#
2-> 0.00 Mate 1. dxe6#
3 0.00 Mate 1. dxe6#
3-> 0.00 Mate 1. dxe6#
4 0.00 Mate 1. dxe6#
4-> 0.00 Mate 1. dxe6#
time=0.00 cpu=100% mat=-6 n=568 fh=100% nps=10K
ext-> chk=18 cap=0 pp=0 1rep=0 mate=0
predicted=0 nodes=568 evals=3 50move=0
endgame tablebase-> probes=0 hits=0
SMP-> split=0 stop=0 data=0/64 cpu=0.00 elap=0.00
crafty% crafty
unable to open book file [./book.bin].
book is disabled
unable to open book file [./books.bin].
EGTB access enabled
using tbpath=./TB
0 piece tablebase files found
Crafty v19.13 (1 cpus)
White(1): 5K2/8/2qk4/2nPp3/3r4/6B1/B7/3R4 w - e6 0 1
White(1): noise 0
noise level set to 0.
White(1): analyze
Analyze Mode: type "exit" to terminate.
clearing hash tables
time surplus 0.00 time limit 30.00 (3:30)
depth time score variation (1)
1 0.00 -1.16 1. Rxd4
1 0.00 Mate 1. dxe6#
1-> 0.00 Mate 1. dxe6#
2 0.00 Mate 1. dxe6#
2-> 0.00 Mate 1. dxe6#
3 0.00 Mate 1. dxe6#
3-> 0.00 Mate 1. dxe6#
4 0.00 Mate 1. dxe6#
4-> 0.00 Mate 1. dxe6#
time=0.00 cpu=100% mat=-6 n=568 fh=100% nps=10K
ext-> chk=18 cap=0 pp=0 1rep=0 mate=0
predicted=0 nodes=568 evals=3 50move=0
endgame tablebase-> probes=0 hits=0
SMP-> split=0 stop=0 data=0/64 cpu=0.01 elap=0.00
So it doesn't appear to fail here no matter how you try it. You do have to use the "noise 0" command or it will just annouce the mate without showing anything since the PV takes just 500 nodes total to search...
Re: Interesting position from Jouni Uski
Posted: Fri May 04, 2007 10:07 pm
by Alessandro Scotti
I have tried again with the same commands posted above and obtained the same result you posted (i.e. correct mate found)... who knows what I did when I tried that for the first time!
