Author: scott farrell
Date: 23:48:10 09/06/02
Go up one level in this thread
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.
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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Last modified: Thu, 15 Apr 21 08:11:13 -0700
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