Plea for a computerchess beginners forum or FAQ

[Rebel]

The chess programming Wiki should be enough, but apart from looking through it for nostalgic purposes, I think it is often too general with regard of topic discussion, and it seems to have at least some mistakes (for example, a few days ago I found a discussion on transposition tables, where the pseudo-code on CPW was deemed to be wrong). The CPW is a great (historical) resource to get you going, but visiting it will only be a start.

Can you please provide a link to the wrong pseudo code in CPW? And a link to the discussion here as well.
I really hope, after more than 10 years of editing CPW, it is a little bit more than nostalgic stuff

Thanks & Regards,
Gerd

Best computer chess website on the Internet Gerd.

[mvanthoor]

Can you please provide a link to the wrong pseudo code in CPW? And a link to the discussion here as well.
I really hope, after more than 10 years of editing CPW, it is a little bit more than nostalgic stuff

Don't get me wrong, the CPW is a great resource to get started with things, and to get to know that concepts exist. I also like to browse it for historical information. For actually programming, I don't really use it.

The discussion / post I was referring to was this one, which I found while I was researching why my engine "forgot" how to mate after adding a TT:

http://www.talkchess.com/forum3/viewtop ... 99#p763944

From the code snippet you show here the CPW implementation looks weird indeed. Why does it store an upperbound each time when (val > alpha and val < beta) ?, storing an exact value at the end of the move loop without knowing whether alpha improved or not seems wrong too.

Normally you would do something like this ...

It's actually possible that this has been changed already. I haven't checked.

[Gerd Isenberg]

Can you please provide a link to the wrong pseudo code in CPW? And a link to the discussion here as well.
I really hope, after more than 10 years of editing CPW, it is a little bit more than nostalgic stuff

Don't get me wrong, the CPW is a great resource to get started with things, and to get to know that concepts exist. I also like to browse it for historical information. For actually programming, I don't really use it.

The discussion / post I was referring to was this one, which I found while I was researching why my engine "forgot" how to mate after adding a TT:

http://www.talkchess.com/forum3/viewtop ... 99#p763944

From the code snippet you show here the CPW implementation looks weird indeed. Why does it store an upperbound each time when (val > alpha and val < beta) ?, storing an exact value at the end of the move loop without knowing whether alpha improved or not seems wrong too.

Normally you would do something like this ...

It's actually possible that this has been changed already. I haven't checked.

OK, it is the concrete code of the CPW-engine by Pawel Koziol and Edmund Moshammer.

https://www.chessprogramming.org/CPW-Engine
https://www.chessprogramming.org/CPW-Engine_search

I intend not to change their original code, but indicating issues and errors for didactical reasons with comments inside or descriptions outside the code, including references, i.e. CCC postings. Pawel already fixed something in 2014 and put the CPW-engine on Git-hub, and is of course welcome to edit his original pages.

http://www.talkchess.com/forum3/viewtopic.php?t=54802
https://github.com/nescitus/cpw-engine/ ... search.cpp

Thanks for pointing that out!

Gerd

[Gerd Isenberg]

Best computer chess website on the Internet Gerd.

Thanks for the compliments, Ed. But don't exaggerate

[jefk]

just make a 'high level' thread with text 'computerchess beginners';
or newbies or something like that. it's obviously a difference
whether you are here for 30 yrs or just looking.
my 2 cnts
www.superchess.blogspot.com