Quick loss

[Henk]

Tested my chess program. Now I played with white myself.
I got:

e2-e4 g8-f6
e4-e5 f6-e4 ?? This knight can not be saved anymore.
d2-d4 e7-e6
g2-g3 b8-c6
f2-f3 e4-g5
h2-h4 f8-b4 Maybe this is why the program does not see it because this check extends the variation
c2-c3 (1 - 0)


How can I prevent f6-e4 from being played ?

Ne4 is a bad move but the real tactical mistake is 4...Nc6
4...f5 or 4...f6 prepare Nf7 and save the knight.

searching to depth 7 or 8 should be clearly enough to avoid Nc6
and if your program cannot get this depth in less than 0.5 second then something is clearly wrong with your search.

What if I played f2f3 instead of g2g3.

[Henk]

Tested my chess program. Now I played with white myself.
I got:

e2-e4 g8-f6
e4-e5 f6-e4 ?? This knight can not be saved anymore.
d2-d4 e7-e6
g2-g3 b8-c6
f2-f3 e4-g5
h2-h4 f8-b4 Maybe this is why the program does not see it because this check extends the variation
c2-c3 (1 - 0)


How can I prevent f6-e4 from being played ?

Ne4 is a bad move but the real tactical mistake is 4...Nc6
4...f5 or 4...f6 prepare Nf7 and save the knight.

searching to depth 7 or 8 should be clearly enough to avoid Nc6
and if your program cannot get this depth in less than 0.5 second then something is clearly wrong with your search.

What if I played f2f3 instead of g2g3.

After f2f3 instead of g2g3, you might get d8h4, g2g3, e4g3, h2g3, h4h1, g1h3 and the queen may be trapped or not. Have to be a really clever program to find out.

[Codesquid]

I think that there must be a bug somewhere.

I agree.

[Henk]

I think that there must be a bug somewhere.

I agree.

Yes you're right. Found another major bug. This time in q-search. aiaiai.

[Henk]

Tested my chess program. Now I played with white myself.
I got:

e2-e4 g8-f6
e4-e5 f6-e4 ?? This knight can not be saved anymore.
d2-d4 e7-e6
g2-g3 b8-c6
f2-f3 e4-g5
h2-h4 f8-b4 Maybe this is why the program does not see it because this check extends the variation
c2-c3 (1 - 0)


How can I prevent f6-e4 from being played ?

Ne4 is a bad move but the real tactical mistake is 4...Nc6
4...f5 or 4...f6 prepare Nf7 and save the knight.

searching to depth 7 or 8 should be clearly enough to avoid Nc6
and if your program cannot get this depth in less than 0.5 second then something is clearly wrong with your search.

What if I played f2f3 instead of g2g3.

After f2f3 instead of g2g3, you might get d8h4, g2g3, e4g3, h2g3, h4h1, g1h3 and the queen may be trapped or not. Have to be a really clever program to find out.

Played again but this time f2f3 instead of g2g3:
My program replies with this PV:

d8-h4 e1-e2 e4-g3 h2-g3 h4-h1
g1-h3 h1-h2 c1-f4 b8-c6 null

Value +2 but his queen is trapped

[asanjuan]

Played again but this time f2f3 instead of g2g3:
My program replies with this PV:

d8-h4 e1-e2 e4-g3 h2-g3 h4-h1
g1-h3 h1-h2 c1-f4 b8-c6 null

Value +2 but his queen is trapped

Not so bad!
Rhetoric plays a similar line thinking 1 second.
Qh4+ Ke2 Ng3+ hxg3 Qxh1 Kf2 Nc6 Nc3 f6 Nb5 Kd8 exf6 gxf6 Bf4 -2,36/13

The position that you reach is good for black since the queen can escape from the corner.
Any materialistic engine would have played the same move. Good job!

[Henk]

Played again but this time f2f3 instead of g2g3:
My program replies with this PV:

d8-h4 e1-e2 e4-g3 h2-g3 h4-h1
g1-h3 h1-h2 c1-f4 b8-c6 null

Value +2 but his queen is trapped

Not so bad!
Rhetoric plays a similar line thinking 1 second.
Qh4+ Ke2 Ng3+ hxg3 Qxh1 Kf2 Nc6 Nc3 f6 Nb5 Kd8 exf6 gxf6 Bf4 -2,36/13

The position that you reach is good for black since the queen can escape from the corner.
Any materialistic engine would have played the same move. Good job!

If instead of Kf2, Nh3 is played the queen is trapped I think.

What search depths do you reach with your program when thinking time is between 2-10 seconds. My average is 7 or 8. Minimum is 6. Sometimes I get 9 and in the end game even more. [Count q-search as 0]. Before I removed these major two bugs I got 10 regularly, so I almost thought my program was playing strong.

I looked at these stockfish analysis examples and they show analysis of over 40 plies. Amazing.

[AlvaroBegue]

If instead of Kf2, Nh3 is played the queen is trapped I think.

You are in a computer chess forum. Use an engine to verify that kind of thing, instead of relying in your poor understanding of the game.

[Henk]

If instead of Kf2, Nh3 is played the queen is trapped I think.

You are in a computer chess forum. Use an engine to verify that kind of thing, instead of relying in your poor understanding of the game.

I don't have one. I don't know how to set up an arbitrary position in Arena.
I can only use my own engine, which I cannot trust.

By the way I encountered this position very often. Maybe I'm the expert (not).

[AlvaroBegue]

If instead of Kf2, Nh3 is played the queen is trapped I think.

You are in a computer chess forum. Use an engine to verify that kind of thing, instead of relying in your poor understanding of the game.

I don't have one. I don't know how to set up an arbitrary position in Arena.
I can only use my own engine, which I cannot trust.

What do you mean you don't have one? There are gazillions of free engines on the web. Stockfish comes to mind. If you don't know how to set positions in Arena (how hard can that be?), you can always talk UCI directly to the engine.

Code: Select all

uci
position startpos moves e2e4 g8f6 e4e5 f6e4
go depth 15

Question for other people in the forum: Is Henk a total troll?