Author: Brian Katz
Date: 13:19:47 12/30/03
Go up one level in this thread
On December 30, 2003 at 15:53:17, Vincent Diepeveen wrote: >On December 30, 2003 at 14:57:00, Brian Katz wrote: > >>On December 30, 2003 at 14:33:19, Vincent Diepeveen wrote: >> >>>On December 30, 2003 at 14:27:01, Brian Katz wrote: >>> >>>Brian use the 6 men pawnless for this idiot position and you will >>>see a mate much sooner. >>> >>>>Do any programs out there find mate in less than 80 moves? >>>> >>>>The winning idea after winning black’s queens, is to corral the Knights, win two >>>>of them, and then get into a K+B+B vs K+N 5 piece Tablebase endgame, which in >>>>some positions, require at least 74 moves. Perhaps more. >>>>If you don't have the 5 piece Tablebases, your program probably will not find >>>>mate. You will need at least the 5 piece endgame mentioned above. >>>> >>>>You may need to set the Tablebase Depth to a setting of 0 rather than the >>>>Default setting of 3. >>>> >>>>[D]n5Kn/8/7k/B6n/8/2B5/2Bq4/4q3 w >>>> >>>>Analysis by Fritz 8: Tablebase Depth set at 0. >>>>Hardware: AMD Athlon XP 2600+ 1 Gig DDR SDRAM >>>> >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Nd5 5.Bb3 Ne7 6.Beg3 >>>> +- (7.22) Depth: 7/12 00:00:00 18kN, tb=45 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Nd5 5.Bb3 Ne7 6.Beg3 >>>> +- (7.22) Depth: 8/14 00:00:00 26kN, tb=46 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Nd5 5.Bb3 Ne7 6.Beg3 >>>> +- (7.22) Depth: 9/16 00:00:00 42kN, tb=71 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Be4 Nd5 6.Bxd5 Kxf4 >>>> +- (7.22) Depth: 10/21 00:00:00 88kN, tb=220 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Be4 Nc4 6.Beg3 Kh5 7.Kg7 >>>> +- (7.28) Depth: 11/21 00:00:00 197kN, tb=529 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Bf2 Nd5 6.Bb3 Nc3 7.Be6+ Kf3 >>>>8.Be5 >>>> +- (7.28) Depth: 12/23 00:00:00 467kN, tb=1594 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Bf2 Nd5 6.Be5 Kf3 7.Bfd4 Ne3 >>>>8.Bd3 >>>> +- (7.31) Depth: 13/25 00:00:00 1018kN, tb=4800 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Bf2 Nd5 6.Be5 Kf3 7.Bfd4 Ne7 >>>>8.Bd3 Nd5 >>>> +- (7.41) Depth: 14/26 00:00:02 2134kN, tb=11604 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Bf2 Nd5 6.Be5 Kf3 7.Bfd4 Nb4 >>>>8.Bf5 Nd5 9.Kg7 >>>> +- (7.44) Depth: 15/29 00:00:04 4887kN, tb=31168 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Bf2 Nd5 6.Be5 Kf3 7.Bfd4 Nb4 >>>>8.Bf5 Nd5 9.Kg7 Nf4 >>>> +- (7.50) Depth: 16/29 00:00:09 10238kN, tb=72603 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Bf2 Nc4 6.Be4 Nb2 7.Bd4 Nc4 >>>>8.Kg7 >>>> +- (7.56) Depth: 17/32 00:00:25 26904kN, tb=234367 >>>>1.Bxd2+! >>>> +- (7.84) Depth: 18/33 00:00:34 36314kN, tb=355809 >>>>1.Bxd2+! >>>> +- (8.13) Depth: 18/35 00:00:54 57493kN, tb=596406 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Ba5 Nd7 5.Kxh8 Nc5 6.Bb6 Nd7 7.Kg7 Kg4 >>>> +- (8.16) Depth: 18/35 00:01:02 66117kN, tb=688821 >>>>1.Bxd2+! >>>> +- (8.44) Depth: 19/37 00:01:09 73772kN, tb=767130 >>>>1.Bxd2+! >>>> +- (8.72) Depth: 19/37 00:01:10 74411kN, tb=798334 >>>>1.Bxd2+! >>>> +- (9.28) Depth: 19/37 00:01:12 76918kN, tb=865923 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Ba5 Nc4 5.Kxh8 Kg4 6.Bd1+ Kf5 7.Be2 Nb2 >>>>8.Bc1 Na4 9.Ba3 Ke4 10.Bd1 >>>> +- (9.59) Depth: 19/40 00:02:17 156703kN, tb=1772123 >>>>1.Bxd2+! >>>> +- (9.88) Depth: 20/39 00:02:28 168406kN, tb=1892491 >>>>1.Bxd2+! >>>> +- (10.16) Depth: 20/39 00:02:30 171306kN, tb=1973122 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Ba5 Nc4 5.Kxh8 Kg4 6.Bac7 Kf3 7.Bc1 Ke2 >>>> +- (10.22) Depth: 20/39 00:04:10 291849kN, tb=3152989 >>>>1.Bxd2+! >>>> +- (10.50) Depth: 21/37 00:04:33 317648kN, tb=3419102 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Ba5 Nc4 6.Bac7 Kf3 7.Bc1 Ke2 >>>>8.Be4 >>>> +- (10.56) Depth: 21/40 00:09:02 634177kN, tb=7029727 >>>>1.Bxd2+! >>>> +- (10.84) Depth: 22/39 00:09:45 683693kN, tb=7568689 >>>>1.Bxd2+! >>>> +- (11.13) Depth: 22/39 00:09:52 691043kN, tb=7790120 >>>>1.Bxd2+! >>>> +- (11.69) Depth: 22/39 00:09:53 692672kN, tb=7915129 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Ba5 Nd7 6.Bd8 >>>> +- (#80) Depth: 22/42 00:15:05 1096525kN, tb=12784411 >>>>1.Bxd2+ Nf4 2.Bxf4+ Kh5 3.Bxe1 Nb6 4.Kxh8 Kg4 5.Ba5 Nd7 6.Bd8 >>>> +- (#80) Depth: 22/42 00:15:24 1119467kN, tb=12908527 >>>> >>>>(Katz, Eatontown 30.12.2003) >>>> >>>>Brian >> >>Yes it is an idiot position, but many puzzles are !! >>I do not have the 6 piece pawnless Tablebases yet. Still deciding if it is >>really worth it. Since I still have a Dial up connection, it would take far too >>long to download. >>What is your opinion on the need for 6 piece pawnless endings? I would much >>prefer to have 6 piece Tablebases involving 1 or more pawns. Such as K+p+p vs >>K+N+p or K+p+p+p vs K+R, K+B, or K+N or KPP vs KPP etc. They would be more >>practical. >> >>As far as idiot positions are concerned, how often do you see 6 piece pawnless >>endigs come up in real chess?? >>Brian > >You cannot compare computer chess with human chess. > >But yes i see regurarly 6 men on the board. For example a teammember of mine a >year ago had to draw in important game KRPP KR, which he drew. But of course >this is at quite a high level. the person in question is fidemaster (Xander >Wemmers). > >This egtb is there nowadays, so for humans this is very nice. > >I'm busy converting some 6 men egtbs now to my own format. This is win/draw/loss >but of course you only care whether a position is a mate or whether it is a >draw. For computerchess win/draw/loss is more useful of course as it fits >practically at the harddisk. > >For nalimov the DTM is more important otherwise he cannot publish them, so i >understand very well why he uses the DTM and he is excused. > >My own egtbs are using the compression from Kadatch, superior compression, well >done Andrew!). Kadatch is of course also used by Nalimov. Kadatch really did a >fine job. It beats zip 2.5 here hands down. really *bigtime*. My own poor >huffman experiments are too slow code anyway to use, but if you compare that >with the compression that Andrew still achieves then this makes his compression >even more impressive. > >Compression of EGTBs is very important. Without it, just forget using EGTBs. > >Without superior compression from Andrew, the diep egtb's would be sized all >together 5.22 T entries / 5 positions/byte = 1.044 TB > >You can imagine that despite harddisks getting near that size quickly now, that >it is useful to compress this very well! > >So from your viewpoint seen, downloading diep's egtbs is worth it, but if you >plan to download the nalimovs that will be i guess about 2 terabyte all >together. > >Even though i could download many of the 6 men generated by Eugene at 5 MB/s >that still took *days* to download. > >The compression ratio that the 6 men get with pawns is about 3.0 or so, because >of all the different mate values which are not so interesting from human >viewpoint. Whether you win in 36 moves or 30 really is not so interesting and >the 50 move rule really is not a big problem practical spoken. The win/draw/loss >of course is much easier to compress. > >So my w/d/l are already smaller without compression than nalimov with. Though >this from scientific publishing viewpoint is not so interesting, practical this >is of course very interesting. > >I'm busy now tuning such to get a better compression for the 6 men. When i have >time and money to buy a dual opteron i will be generating a 7 men. That will be >a pawnless one though to start with :) > >Right now the only problem with the egtbs is time. People just count how many >points you get in a tournament, no one is interested in whether you can run on a >supercomputer or have your own egtb format. > >Note that in contradiction to what people say the only problem when generating >EGTBs is cpu speed, *not* i/o speed. > >The simple example is that when generating for example white to move mate in 30, >your harddisk is easily getting tens of megabytes a second. So say 80MB/s for >slow SCSI harddisk (i have U160 at my S2462) that's a mighty > >640 million positions a second. > >The generator however is running at a way slower speed. When test generating >some at a quad Xeon 500Mhz, it was getting 500k positions a second a cpu. > >... I agree that 6 man endings come up quite regularly, but my question was "How often do you see 6 man pawnless endings come up?" The point being that, Is it really necessary to take up so much space on a Harddrive for endings of that nature, other than for the fun of just having it? Brian
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