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Subject: Re: Please help with a bug in my program - with Diagram - after RDC2

Author: Robert Hyatt

Date: 19:51:46 09/07/02

Go up one level in this thread


On September 07, 2002 at 02:48:10, scott farrell wrote:

>On September 06, 2002 at 21:38:23, Robert Hyatt wrote:
>>
>>Exactly how long does it take you to find the mate if _you_ play the
>>rook move yourself? I mean you play the move and let your program search
>>the resulting position here...
>>
>>Then we can figure out if your extensions are working by seeing how
>>deep you have to go to find that mate from the white side after black
>>blows it...
>
>The results of the rook search is below.
>
>I think I found it - my extensions when there is a nullthreat (ie. when the
>nullmove returns <= -INFINITY) seemed to cause this search to go the entire
>brute force distance of 12 plies to see the mate in 6. I am caching the
>nullthreat in the hashtable as well.


Here is a big question.  How are you storing "depth" in the hash table?

IE you aren't first adjusting for extensions and then storing that???  If
so that's a bug...






>
>The following analysis is with nullthreat extensions disabled.
>
>I just assumed adding more extensions was always a good thing, at worst it would
>cause more nodes to be searched at the same ply.
>
>[D] 7k/pp3p1p/1np5/5N2/1P2P1NR/7P/2r3PK/2r5/ w - - 0 50
>
>d2/1(1)  -8.67  0.0secs  6  H4H7 H8H7
>d2/2(1)  -5.38  0.0secs  76  E4E5 B6C4
>d2/2(2)  -4.94  0.06secs  153  G4H6 B6C4
>d2/2(3)  -4.62  0.06secs  258  F5E3 C2C3
>d2/2(3)  -4.2  0.22secs  368  G4E3 C2C3
>->2/2(3)  -4.2  0.22secs  382  G4E3 C2C3
>d3/4(2)  -3.77  0.28secs  544  G4E3 C2C3 E3C2
>->3/4(2)  -3.77  0.28secs  655  G4E3 C2C3 E3C2
>d4/6(3)  -4.43  0.33secs  1564  G4E3 C2C3 H4H6 B6C4
>->4/6(3)  -4.43  0.39secs  2128  G4E3 C2C3 H4H6 B6C4
>d5/8(3)  -3.63  0.39secs  4125  G4E3 C2C3 H4H6 B6A4 H6D6
>d5/8(3)  -2.54  0.44secs  8399  G4H6 F7F6 H6F7 H8G8
>d5/8(3)  0.85  0.44secs  10217  G4F6 C2G2
>->5/8(3)  0.85  0.44secs  10625  G4F6 C2G2
>d6/9(2)  2.3  0.5secs  13188  G4F6 C1H1
>->6/9(2)  2.3  0.5secs  14228  G4F6 C1H1
>d7/10(2)  2.3  0.55secs  16891  G4F6 C1H1 H2H1
>->7/10(2)  2.3  0.55secs  17160  G4F6 C1H1 H2H1
>d8/14(2)  3.21  0.72secs  30871  G4F6 C2G2 H2G2 C1C2 G2G3 C2C3 G3F4 B6D5
>->8/14(2)  3.21  0.72secs  31682  G4F6 C2G2 H2G2 C1C2 G2G3 C2C3 G3F4 B6D5
>d9/16(2)  501.0  1.05secs  63682  G4F6 C2G2
>->9/16(2)  501.0  1.05secs  63682
>, D9/16(2): 501.0 : G4F6 , 1.05/3600.0 secs - NPS: 60650  asp%:100, bf:1.94,
>avbf:1.42 AvCut: 0.8 itdeep:770/1459, ks:-24/-8, pp:0(0)/0(0), mateN:
>1364000001, mateNQ: 2000009, N: 36391, nmN: 26624, nmNq: 257, qN: 410, dN: 91,
>nmTrys:8178/82/, nm%:53/2/, cHit: 84%, cqHit: 17%, cUse%: 90, bc%:85, pv%:51,
>pvs%:93,pv: , , pond:0/50 saving 0 msecs
>
>here is the analysis with null threat enabled:
>d2/1(1)  -8.67  0.0secs  6  H4H7 H8H7
>d2/3(2)  -5.38  0.06secs  77  E4E5 B6C4
>d2/3(2)  -4.94  0.06secs  155  G4H6 B6C4
>d2/3(3)  -4.62  0.11secs  260  F5E3 C2C3
>d2/3(3)  -4.2  0.28secs  370  G4E3 C2C3
>->2/3(3)  -4.2  0.28secs  384  G4E3 C2C3
>d3/4(2)  -3.77  0.28secs  546  G4E3 C2C3 E3C2
>->3/4(2)  -3.77  0.33secs  657  G4E3 C2C3 E3C2
>d4/6(3)  -4.43  0.39secs  1566  G4E3 C2C3 H4H6 B6C4
>->4/6(3)  -4.43  0.39secs  2160  G4E3 C2C3 H4H6 B6C4
>d5/9(3)  -3.63  0.44secs  4196  G4E3 C2C3 H4H6 B6A4 H6D6
>d5/10(3)  -2.54  0.44secs  8678  G4H6 F7F6 H6F7
>d5/10(3)  2.31  0.5secs  12082  G4F6 C2G2
>->5/10(3)  2.31  0.5secs  12325  G4F6 C2G2
>d6/11(2)  1.99  0.55secs  14099  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3
>->6/11(2)  1.99  0.55secs  15154  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3
>d7/6(1)  1.99  0.55secs  16136  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3
>->7/9(1)  1.99  0.55secs  16465  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3
>d8/15(2)  1.79  0.66secs  25839  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3 H4H5 F7F6
>->8/15(2)  1.79  0.66secs  26699  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3 H4H5 F7F6
>d9/8(2)  1.79  0.72secs  30719  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3 H4H5 F7F6
>->9/8(2)  1.79  0.72secs  30800  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F5E3 H8G7 F6H7
>C3D3 H4H5 F7F6
>d10/19(2)  9.61  1.43secs  123319  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F3G4 C3G3 F5G3
>H8G7 F6H7 B6D7 H4H5 G7G6
>->10/19(2)  9.61  1.43secs  123828  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F3G4 C3G3 F5G3
>H8G7 F6H7 B6D7 H4H5 G7G6
>d11/10(2)  9.61  1.7secs  147179  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F3G4 C3G3 F5G3
>H8G7 F6H7 B6D7 H4H5 G7G6
>->11/10(2)  9.61  1.7secs  147260  G4F6 C2G2 H2G2 C1C2 G2F3 C2C3 F3G4 C3G3 F5G3
>H8G7 F6H7 B6D7 H4H5 G7G6
>d12/22(2)  501.0  3.35secs  346114  G4F6 C2G2
>->12/22(2)  501.0  3.35secs  346114
>, D12/22(2): 501.0 : G4F6 , 3.35/3600.0 secs - NPS: 103318  asp%:100, bf:6.11,
>avbf:2.5 AvCut: 0.5 itdeep:1232/3400, ks:-24/-8, pp:0(0)/0(0), mateNQ: 1000010,
>threatN: 7/58, N: 207822, nmN: 137204, nmNq: 609, qN: 479, dN: 347,
>nmTrys:24984/728/, nm%:44/7/, cHit: 70%, cqHit: 15%, cUse%: 73, bc%:83, pv%:40,
>pvs%:94,pv: , , pond:0/50 saving 0 msecs
>
>looking at the above analysis it seems as though it doesnt see G4F6 C2G2 H2G2
>C1C2 G2F3 C2C3 F3G4 C3G3 KxG3
>
>[D] 7k/pp3p1p/1np2N2/5N2/1P2P1KR/6rP/8/8/ w - - 0 50
>
>My guess is given I have R=2 at that point - its is overlooking this in a null
>move blindspot.
>
>When I search the position at the point it should do KxG3 - it sees that KxG3
>
>d2/2(1)  7.99  0.0secs  20  F5G3 H8G7
>d2/2(1)  8.69  0.0secs  53  G4G3 B6C4
>->2/2(3)  8.69  0.0secs  61  G4G3 B6C4
>d3/3(2)  501.0  0.06secs  168  G4G3 B6C4
>->3/3(2)  501.0  0.06secs  168
>, D3/3(2): 501.0 : G4G3 , 0.06/3600.0 secs - NPS: 2800  asp%:100 AvCut: 0.2 itde
>ep:13/24, ks:0/0, pp:0(0)/0(0), mateN: 12000000, N: 143, nmN: 19, nmNq: 2, qN: 4
>, nmTrys:14/0/, nm%:0/0/, cHit: 67%, cqHit: 51%, cUse%: 70, bc%:62, pv%:100, pvs
>%:17,pv: , , pond:0/50 saving 0 msecs
>
>
>
>This is crafty's analysis of the same board:
>                7     0.07  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>                7->   0.07  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>                8     0.08  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>                8->   0.08  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>                9     0.11  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>                9->   0.12  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>               10     0.18  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>               10->   0.20  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>               11     0.27  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>               11->   0.32  Mat06   1. Nf6 Rxg2+ 2. Kxg2 Rc2+ 3. Kg3 Rc3+
>                                    4. Kg4 Rxh3 5. Rxh3 a5 6. Rxh7#
>              time=0.32  cpu=103%  mat=-3  n=241457
>  fh=84%  nps=754k
>              ext-> chk=19857 cap=330 pp=14 1rep=1168 mate=3775
>              predicted=0  nodes=241457  evals=10527
>              endgame tablebase-> probes done=0  successful=0



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