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Subject: Quiescent explosion?

Author: Magoo

Date: 13:34:11 05/02/03


Hello, i have tested my move_gen, it works, i implemented the perft command and
tested depth = 6, also tried an middlegame position to depth 5.
SO, that means my program works with MinMax (i think), now i get this with
AlphaBeta+Eval (that is no quiescent):
bRbNbBbQbKbBbNbR
bPbPbPbP..bPbPbP
................
........bP......
......wPwP......
................
wPwPwP....wPwPwP
wRwNwBwQwKwBwNwR
ply:3
Depth:1, Nodes:30, QNodes:0 Time:0 sec, Nps:0, Value:-116 move e5d4
Depth:2, Nodes:97, QNodes:0 Time:0 sec, Nps:0, Value:18 move e5d4
Depth:3, Nodes:1096, QNodes:0 Time:0 sec, Nps:0, Value:-115 move f8b4
Depth:4, Nodes:4839, QNodes:0 Time:0 sec, Nps:0, Value:25 move d8h4
Depth:5, Nodes:46015, QNodes:0 Time:6 sec, Nps:7669, Value:-113 move d8h4
best_move = move d8h4

And now with Quiescent (not same position):
bR..bBbQbKbBbNbR
bPbPbPbPbPbPbPbP
....bN..........
................
......wPwP......
................
wPwPwP....wPwPwP
wRwNwBwQwKwBwNwR
ply:3
Depth:1, Nodes:51, QNodes:27 Time:0 sec, Nps:0, Value:-14 move e7e5
Depth:2, Nodes:602, QNodes:381 Time:0 sec, Nps:0, Value:7 move d7d5
Depth:3, Nodes:2786, QNodes:1543 Time:0 sec, Nps:0, Value:-14 move e7e5
Depth:4, Nodes:13219, QNodes:8023 Time:1 sec, Nps:13219, Value:9 move g8f6
Depth:5, Nodes:209098, QNodes:131495 Time:32 sec, Nps:6534, Value:-13 move d7d5
best_move = move d7d5

So, adding Quiescent to my program slows it down by much, returning only eval()
in alphabeta with History/MVV-LVA ordering takes approx 5-7sec (depth=5) and
Nodes is around 50 000 - 70 000 for depth 5.
My conclusion is that the alphabeta prunning is bad, i have compared to other
"simple" programs and they get around 50 000 Nodes at depth 5 INCLUDING
Q-search. If i could get that my program would be much faster (because Q-nodes
are faster, only captures are generated.
My move list for position above (alphabeta+eval), s=score, best_move comes last:
s: 0 move a7a5
s: 0 move a7a6
s: 0 move b7b5
s: 0 move b7b6
s: 0 move c7c5
s: 0 move c7c6
s: 0 move d7d5
s: 0 move d7d6
s: 0 move f7f5
s: 0 move f7f6
s: 0 move g7g5
s: 0 move g7g6
s: 0 move h7h5
s: 0 move h7h6
s: 0 move b8a6
s: 0 move d8e7
s: 0 move d8f6
s: 0 move e8e7
s: 0 move f8e7
s: 0 move f8d6
s: 0 move f8c5
s: 0 move g8h6
s: 0 move g8e7
s: 4 move b8c6
s: 5 move d8g5
s: 10 move f8a3
s: 17 move d8h4
s: 22 move f8b4
s: 129 move g8f6
cap_move: s: 1000061 move e5d4

This gives 7 good moves, the first one being a capture.



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Last modified: Thu, 15 Apr 21 08:11:13 -0700

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