Does YOUR Engine Play This Sac? Is it Sound?

Discussion of anything and everything relating to chess playing software and machines.

Moderators: bob, hgm, Harvey Williamson

Forum rules
This textbox is used to restore diagrams posted with the [d] tag before the upgrade.
BrendanJNorman
Posts: 2076
Joined: Sun Feb 07, 2016 11:43 pm
Full name: Brendan J Norman

Does YOUR Engine Play This Sac? Is it Sound?

Post by BrendanJNorman » Mon Mar 30, 2020 3:01 am

So...I just played the following 3 2 game against some 2100 type guy on chess.com...



A nice one, right?

What I'm wondering is 1. If your engine plays my knight sac (15.Ndb5!?) and 2. If this move is objectively winning.



Move: 15.Ndb5!?

I played this move because I get two pawns, tons of space and my opponent can barely move, but these are human considerations...what do the beasts say?

User avatar
MikeB
Posts: 3933
Joined: Thu Mar 09, 2006 5:34 am
Location: Pen Argyl, Pennsylvania

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by MikeB » Mon Mar 30, 2020 4:41 am

It's a good move , 2nd best move out of 46. Qf2 is better. It improved your game, not sure if I would call it winning - but certainly a move to be proud of.

info depth 47 seldepth 83 multipv 1 score cp 112 nodes 44987863136 nps 79993639 hashfull 997 tbhits 0 time 562393 pv c2f2 g7f8 f4f5 c7d8 d4b3 b7b6 b3c5 b6c5 c3a4 d8e7 f2g3 f8g7 f5g6 h7g6 g3d6 e7d6 d1d6 g7f8 d6d2 d7e5 b2b3 e5f3 g2f3 c8h3 f1d1 f7f5 a4b6 a8a7 b6d7 f8e7 d7c5 f5e4 c5e4 a7b7 e3g5 h3f5 g5e7 f5e4 f3e4 b7e7 d1g1 g8f7 d2d6 e7e4 d6c6 e4e2 g1f1 f7g7 c4c5 e2a2 f1g1 a2b2 c6g6 g7f7 c5c6 b2b3 c6c7 b3c3

search d4b5 only
info depth 37 seldepth 62 multipv 1 score cp 85 nodes 2964660595 nps 84068073 hashfull 853 tbhits 0 time 35265 pv d4b5 c6b5 c3b5 c7b8 b5d6 e8e6 e4e5 a8a6 d6b5 b7b6 f3d5 e6e7 c2f2 c8b7 f2h4 g7f8 b5c3 a6a8 f1f3 b7d5 c4d5 b8d8 h4h3 f8g7 d5d6 e7e6 c3d5 d7e5 f4e5 e6e5 f3f1 d8d6 h3f3 a8f8 e3f4 g8h8 f4e5 g7e5 d1e1 h8g8 d5f6 e5f6 f3f6 d6f6 f1f6

BrendanJNorman
Posts: 2076
Joined: Sun Feb 07, 2016 11:43 pm
Full name: Brendan J Norman

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by BrendanJNorman » Mon Mar 30, 2020 4:59 am

MikeB wrote:
Mon Mar 30, 2020 4:41 am
It's a good move , 2nd best move out of 46. Qf2 is better. It improved your game, not sure if I would call it winning - but certainly a move to be proud of.
Thanks Mike.

Yeah I seen that Ethereal 12 prefers Qf2, but I think this move is very hard for humans to understand.

The idea is to keep the idea of Ndb5 up your sleeve, whilst also adding the option of a strong e5! push (queen and bishop battery target knight on c5 in some lines).

On my slow GPU, Leelenstein liked Ndb5 as well...

It was interesting checking with old engines too... Deep Fritz 10 plays Ndb5 instantly, while Deep Junior 11 doesn't even consider it.
MikeB wrote:
Mon Mar 30, 2020 4:41 am
info depth 47 seldepth 83 multipv 1 score cp 112 nodes 44987863136 nps 79993639 hashfull 997 tbhits 0 time 562393 pv c2f2 g7f8 f4f5 c7d8 d4b3 b7b6 b3c5 b6c5 c3a4 d8e7 f2g3 f8g7 f5g6 h7g6 g3d6 e7d6 d1d6 g7f8 d6d2 d7e5 b2b3 e5f3 g2f3 c8h3 f1d1 f7f5 a4b6 a8a7 b6d7 f8e7 d7c5 f5e4 c5e4 a7b7 e3g5 h3f5 g5e7 f5e4 f3e4 b7e7 d1g1 g8f7 d2d6 e7e4 d6c6 e4e2 g1f1 f7g7 c4c5 e2a2 f1g1 a2b2 c6g6 g7f7 c5c6 b2b3 c6c7 b3c3

search d4b5 only
info depth 37 seldepth 62 multipv 1 score cp 85 nodes 2964660595 nps 84068073 hashfull 853 tbhits 0 time 35265 pv d4b5 c6b5 c3b5 c7b8 b5d6 e8e6 e4e5 a8a6 d6b5 b7b6 f3d5 e6e7 c2f2 c8b7 f2h4 g7f8 b5c3 a6a8 f1f3 b7d5 c4d5 b8d8 h4h3 f8g7 d5d6 e7e6 c3d5 d7e5 f4e5 e6e5 f3f1 d8d6 h3f3 a8f8 e3f4 g8h8 f4e5 g7e5 d1e1 h8g8 d5f6 e5f6 f3f6 d6f6 f1f6
What software are you exporting these PV from? Arena or something? A bit hard to read for me. :)

User avatar
MikeB
Posts: 3933
Joined: Thu Mar 09, 2006 5:34 am
Location: Pen Argyl, Pennsylvania

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by MikeB » Mon Mar 30, 2020 5:03 am

BrendanJNorman wrote:
Mon Mar 30, 2020 4:59 am
MikeB wrote:
Mon Mar 30, 2020 4:41 am
It's a good move , 2nd best move out of 46. Qf2 is better. It improved your game, not sure if I would call it winning - but certainly a move to be proud of.
Thanks Mike.

Yeah I seen that Ethereal 12 prefers Qf2, but I think this move is very hard for humans to understand.

The idea is to keep the idea of Ndb5 up your sleeve, whilst also adding the option of a strong e5! push (queen and bishop battery target knight on c5 in some lines).

On my slow GPU, Leelenstein liked Ndb5 as well...

It was interesting checking with old engines too... Deep Fritz 10 plays Ndb5 instantly, while Deep Junior 11 doesn't even consider it.
MikeB wrote:
Mon Mar 30, 2020 4:41 am
info depth 47 seldepth 83 multipv 1 score cp 112 nodes 44987863136 nps 79993639 hashfull 997 tbhits 0 time 562393 pv c2f2 g7f8 f4f5 c7d8 d4b3 b7b6 b3c5 b6c5 c3a4 d8e7 f2g3 f8g7 f5g6 h7g6 g3d6 e7d6 d1d6 g7f8 d6d2 d7e5 b2b3 e5f3 g2f3 c8h3 f1d1 f7f5 a4b6 a8a7 b6d7 f8e7 d7c5 f5e4 c5e4 a7b7 e3g5 h3f5 g5e7 f5e4 f3e4 b7e7 d1g1 g8f7 d2d6 e7e4 d6c6 e4e2 g1f1 f7g7 c4c5 e2a2 f1g1 a2b2 c6g6 g7f7 c5c6 b2b3 c6c7 b3c3

search d4b5 only
info depth 37 seldepth 62 multipv 1 score cp 85 nodes 2964660595 nps 84068073 hashfull 853 tbhits 0 time 35265 pv d4b5 c6b5 c3b5 c7b8 b5d6 e8e6 e4e5 a8a6 d6b5 b7b6 f3d5 e6e7 c2f2 c8b7 f2h4 g7f8 b5c3 a6a8 f1f3 b7d5 c4d5 b8d8 h4h3 f8g7 d5d6 e7e6 c3d5 d7e5 f4e5 e6e5 f3f1 d8d6 h3f3 a8f8 e3f4 g8h8 f4e5 g7e5 d1e1 h8g8 d5f6 e5f6 f3f6 d6f6 f1f6
What software are you exporting these PV from? Arena or something? A bit hard to read for me. :)
just raw data from the command line ... sorry

Terje
Posts: 156
Joined: Tue Nov 19, 2019 3:34 am
Location: https://github.com/TerjeKir/weiss
Full name: Terje Kirstihagen

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by Terje » Mon Mar 30, 2020 11:34 am

While hardly a beast, Weiss plays Ndb5 almost instantly (slightly preferring it over Qf2) :)

jp
Posts: 1320
Joined: Mon Apr 23, 2018 5:54 am

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by jp » Mon Mar 30, 2020 12:39 pm

Komodo 13.2, PV=2:

depth=25
+0.96 15.Qf2 Ra6 16.Nde2 Bf8 17.b3 b6 18.h3 Bb7 19.Rd2 Nf6 20.Ng3 Nfd7 21.Rfd1 Raa8 22.Nge2 Nf6 23.g4 h6 24.Qg2 Nh7 25.h4 Qe7 26.g5 Rad8 27.Bd4 Bg7
+0.83 15.Ndb5 cxb5 16.Nxb5 Qb8 17.Nxd6 Re6 18.e5 Ra6 19.Nb5 b6 20.Qf2 Bb7 21.Bd5 Re7 22.Qh4 Bf8 23.Rf3 Ra8 24.Rh3 h5 25.Nc3 Bxd5 26.cxd5 Re8 27.d6 Bg7 28.Nd5 Qb7 29.Kg1 Ne4 30.Nc7 Rad8 31.Nxe8 Rxe8 32.Rf3

zullil
Posts: 6073
Joined: Mon Jan 08, 2007 11:31 pm
Location: PA USA
Full name: Louis Zulli

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by zullil » Mon Mar 30, 2020 1:14 pm

Lc0 (384x30-swa-320000.pb)

Nodes: 17.9M, N/s: 11.1k, Time: 26m 47s

76.9% Qf2 Rb8 h3 a4 Ndb5 cxb5 Nxb5 Qd8 Nxd6 b6 e5 Bb7 Nxe8 Qxe8 Bd5 Na6 Qf3 Ndc5 Bd4 Bc8 Rfe1 Ne6 Bc3 Qe7 f5 gxf5 Qxf5 Nf8 e6 Bxe6 Bxg7 Kxg7 Qe5+ Qf6 Qg3+ Qg6 Qe3 Kg8 Qf4 Qg7 Qd6 Qxb2 Re3 Re8 (N: 17.4M, WDL: 673 193 134, P: 3.68%)

72.5% Ndb5 cxb5 Nxb5 Qd8 Nxd6 Bf8 Nxe8 Qxe8 e5 Nb8 g4 Nc6 Qf2 Ne6 Qg2 Ng7 Bd5 Ne7 Be4 Nc6 Bd2 Ra6 f5 Nxe5 Bd5 gxf5 gxf5 Kh8 f6 Ne6 Rde1 (N: 86.9k, WDL: 619 212 169, P: 8.51%)

67.0% b3 Nf6 h3 a4 Bf2 axb3 axb3 Qa5 Rb1 Qb4 Rfd1 Bd7 Be1 Qb6 b4 Ncxe4 Bxe4 Nxe4 Nxe4 Bxd4 c5 Qa6 Rxd4 Bf5 cxd6 Qf1+ (N: 57.5k, WDL: 528 284 188, P: 12.54%)

User avatar
xr_a_y
Posts: 1104
Joined: Sat Nov 25, 2017 1:28 pm
Location: France

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by xr_a_y » Mon Mar 30, 2020 1:36 pm

Curiously Minic is playing it instantly !

Code: Select all

1 58 0 44 	c2f2 
2 177 0 82 	c2f2 g7d4 
3 177 0 122 	c2f2 g7d4 e3d4 
4 35 0 509 	d4e2 c5e6 a2a3 d7f6 
5 39 0 736 	d4e2 d7f6 h2h3 c5e6 e2g3 
6 28 0 1344 	a2a3 d7f6 e3f2 c8e6 d4e6 c5e6 
7 -4 0 3134 	h1g1 d7f6 d4e2 c8e6 e3c5 d6c5 !
7 21 0 4334 	a2a3 d7f6 b2b4 a5b4 a3b4 f6g4 f3g4 
8 21 0 5032 	a2a3 d7f6 b2b4 a5b4 a3b4 f6g4 f3g4 c8g4 
9 68 1 10588 	d4b5 c6b5 c3b5 c7c6 d1d6 d7f6 ?
9 21 2 13953 	a2a3 d7f6 b2b4 a5b4 a3b4 f6g4 f3g4 c8g4 
10 41 3 21400 	d4b5 c6b5 c3b5 c7d8 b5d6 e8e7 e4e5 d8c7 c2e2 c5e6 f3d5 d7c5 
11 41 3 23074 	d4b5 c6b5 c3b5 c7d8 b5d6 e8e7 e4e5 d8c7 c2e2 c5e6 f3d5 d7c5 
12 23 9 70622 	d4b5 c6b5 c3b5 c7d8 b5d6 e8e7 e4e5 d8c7 f3d5 d7b6 d5f3 c8e6 e3c5 
13 44 9 73901 	d4b5 c6b5 c3b5 c7d8 b5d6 e8e7 e4e5 h7h6 c2f2 ?
13 76 14 113273 	d4b5 c6b5 c3b5 c7d8 b5d6 e8e7 e4e5 h7h6 c2f2 e7e6 ?
13 84 29 264046 	d4b5 c6b5 c3b5 c7b8 b5d6 e8e6 e4e5 g7f8 f3d5 f8d6 d5e6 d6e7 e6d7 c5d7 
14 66 32 298132 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 e4e5 g7f8 g2g3 f8d6 d1d6 !
14 83 43 415758 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 e4e5 g7f8 c2f2 b8c7 d6b5 c7b6 d1d5 a5a4 f1d1 f8e7 b5d6 e7d6 d5d6 
15 83 44 426847 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 e4e5 g7f8 c2f2 b8c7 d6b5 c7b6 d1d5 a5a4 f1d1 f8e7 b5d6 
16 69 47 449118 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 c2f2 g7f8 f2e2 !
16 46 54 515331 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 c2f2 g7f8 e4e5 c5e6 d1d5 f8d6 d5d6 a8a6 h1g1 !
16 64 95 988474 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 e4e5 g7f8 c2f2 c5e6 c4c5 f8g7 f3e2 a5a4 f4f5 g6f5 d6f7 f5f4 f7d8 f4e3 f2f7 g8h8 ?
16 59 107 1112192 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 e4e5 g7f8 c2f2 c5e6 c4c5 b8c7 d1d5 f8g7 f1d1 a5a4 a2a3 g7h6 f2h4 h6g7 
17 59 138 1458129 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 e4e5 g7f8 c2f2 c5e6 c4c5 b8c7 d1d5 f8g7 f1d1 a5a4 a2a3 g7h6 
18 69 147 1529930 	d4b5 c6b5 c3b5 c7b8 b5d6 e8d8 d6f7 g8f7 e3c5 d7c5 d1d8 c5e6 d8d2 a5a4 f3e2 f7e8 c4c5 e6c5 ?
18 86 172 1782629 	d4b5 c6b5 c3b5 c7b8 ?
18 66 192 1965925 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 c5e6 c4c5 b8c7 d6b5 c7d8 c5c6 b7c6 c2c6 a8b8 b5d6 d7e5 f4e5 b8b2 d6c8 
19 58 218 2256160 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d1d5 c5e6 a2a3 f8d8 d5d1 a5a4 !
19 66 238 2483231 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d1d5 c5e6 f1d1 g7h6 d6c8 f8d8 c2d2 a8c8 d5d7 e6f4 ?
19 44 330 3522792 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d1d5 c5e6 f1d1 d7b8 d6b5 c7e7 b5c3 b8c6 c2f2 f8d8 a2a3 g7h6 d5d8 c6d8 !
19 52 350 3745058 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d1d5 c5e6 f1d1 d7b8 c2f2 b8c6 e3b6 c7b8 g2g3 e6c7 d6c8 b8c8 d5d3 c6b4 d3d7 c7e6 
20 52 374 4024454 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d1d5 c5e6 f1d1 d7b8 c2f2 b8c6 e3b6 c7b8 g2g3 e6c7 d6c8 b8c8 d5d3 c6b4 
21 46 422 4599818 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d1d5 c5e6 f1d1 d7b8 c2f2 !
21 52 483 5314559 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 ?
21 52 602 6571572 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d6b5 c7b8 f3d5 c5e6 b5d6 b8c7 d6f7 f8f7 d5e6 d7e5 e6c8 a8c8 f4e5 g7e5 f1f7 
22 52 791 8628248 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d6b5 c7b8 f3d5 c5e6 b5d6 b8c7 d6f7 f8f7 d5e6 d7e5 e6c8 a8c8 f4e5 g7e5 f1f7 c7f7 
23 46 919 10043760 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d6b5 c7b8 !
23 52 1084 11877422 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 ?
23 70 1899 20911087 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d6b5 c7b8 d1d5 c5e6 f1d1 ?
23 66 1994 22008222 	d4b5 c6b5 c3b5 c7b8 b5d6 e8f8 e4e5 b8c7 d6b5 c7b8 d1d5 c5e6 f1d1 f8d8 b5d6 e6c7 d5d3 c7e6 c2d2 e6f4 e3f4 d7e5 f4e5 g7e5 d3d5 d8d6

acase
Posts: 728
Joined: Wed Mar 15, 2006 12:14 am
Location: Columbus, Ohio USA
Full name: Andrew R Case

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by acase » Tue Mar 31, 2020 6:45 pm

BrendanJNorman wrote:
Mon Mar 30, 2020 3:01 am
So...I just played the following 3 2 game against some 2100 type guy on chess.com...



A nice one, right?

What I'm wondering is 1. If your engine plays my knight sac (15.Ndb5!?) and 2. If this move is objectively winning.



Move: 15.Ndb5!?

I played this move because I get two pawns, tons of space and my opponent can barely move, but these are human considerations...what do the beasts say?


Yep, that is a nice move and most engines do consider that move 2nd only to 15.Qf2, however it looks like 15.g4 with the idea of 16.g5 also works here (probably no better or no worse than 15.Ndb5 and 15.Qf2). Personally I like 15.Ndb5 the best because it looks like you're using tactics to achieve a strategical goal.

Alayan
Posts: 252
Joined: Tue Nov 19, 2019 7:48 pm
Full name: Alayan Feh

Re: Does YOUR Engine Play This Sac? Is it Sound?

Post by Alayan » Tue Mar 31, 2020 9:43 pm

15. Ndb5 is a really nice move.

Post Reply