[xboard/crafty] # of positions examined, deepest ply

[Mike_Tyson]

After crafty made a move, I would like to know how many positions it examined. I.e. I want to know how many nodes in the search tree it visited before deciding on the best move.

Also, it would be interesting to know at which ply (at which depth in the tree) it found it's best move.

Is this possible?

--
I am using xboard 4.5.2+ with crafty v23.1.

[H.G.Muller]

The engine-output window contains that information. It can be openened through the View->Engine Output menu item. For each search depth it displays score, time and number of nodes, as well as PV (the first moe of which is the best move from the current position).

[Mike_Tyson]

1.) Thanks, I tried that. The engine output window looks interesting, but what happens is this: after I make move, the engine output window is cleared and the lines of text pour in. So far so good. Now crafty makes a move and immediately clears the window again, filling it with new, other output! I think it shows speculative moves while I am thinking. The problem is, I simply do not have enough time to study the output it made while it was computing the first response move!

Even if I go back one move, with the "<" button, the engine output does not display the previous computation.

Is there any way to stop the engine output of clearing it's content each time a move is made? The way it's now it's just to fast.

2.) I am still not sure what the columns *exactly* mean. For me it looks like this:

Code: Select all

 13   +0.18   6.7M   1:04.82   2. ... e6 3. e3 Be7 4. Bb5 O-O 5. O-O d6 6. Nc3 Na6 7. Ng5 Bd7 8. Bd3 Bc6
 12   +0.10   2.6M   0:32.15   2. ... e6 3. e4 Nxe4 4. Bd3 d5 5. O-O Nc6 6. Nbd2 Nf6 7. Nb3 Nb4 8. Bb5+ Bd7
 12   +0.10   977228   0:08.79   2. ... e6 3. e4 Nxe4 4. Bd3 d5 5. O-O Nc6 6. Nbd2 Nf6 7. Nb3 Nb4 8. Bb5+ Bd7
 11   +0.02   562391   0:06.12   2. ... e6 3. e4 Nxe4 4. Bd3 d5 5. O-O Nc6 6. Nbd2 f5 7. Nxe4 dxe4
 11   +0.02   515798   0:05.82   2. ... e6 3. e4 Nxe4 4. Bd3 d5 5. O-O Nc6 6. Nbd2 f5 7. Nxe4 dxe4

 11   -0.03   1.1M   0:06.11   1. ... Nf6 2. Nf3 e6 3. e4 Nxe4 4. Bd3 d5 5. O-O Nd7 6. Nbd2 Ndf6 7. Nxe4 Nxe4


I think it's this:
column 1: ply at which the search stopped
column 2: score
column 3: nodes per second before reaching this position
column 4: cpu-time spent on computation until reaching this node, and only the time relevant for this part of the search tree, *not* wall-clock time
column 5: possible moves for next ply?

Could someone confirm or correct this?

[H.G.Muller]

The window is cleared before each search, and when Crafty is set to "Ponder next move" (in the General Options dialog), it starts to immediately do that after it completed the search for its own move. The last line of the previous search is still printed below the new search output for you to look at, though. If you want the output to stay, you should switch pondering off.

You can also switch Crafty to Analysis (Mode menu), in stead of letting it play a game; then it will never move, so that the window willnever be cleared. Unless you move yourself, or use < or >, then Crafty will start thinking about the new position, (i.e. start a new search), leading to new output.

meaning:
1) Depth of the searh to which this line applies.
3) total nodes searched in the current search
4) wall-clock time needed spent so far in the current search
5) principal variation (i.e.how the game will continue when both sides keep playing their best moves)

[Guenther Simon]

1.) Thanks, I tried that. The engine output window looks interesting, but what happens is this: after I make move, the engine output window is cleared and the lines of text pour in. So far so good. Now crafty makes a move and immediately clears the window again, filling it with new, other output! I think it shows speculative moves while I am thinking. The problem is, I simply do not have enough time to study the output it made while it was computing the first response move!

The easiest solution to your wish is just to put the debug flag on. This way all the info is stored in a debug file.
Now you have forever time to investigate what happened during thinking time of any engine you like.

Guenther