Search found 1215 matches

by mjlef
Tue Jun 19, 2007 7:43 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: A personal introduction
Replies: 4
Views: 2857

Re: A personal introduction

I see Ed added stuff for pawn evaulations to his great Rebel writeup. Now I owe him at least 2 nice meals! Great stuff. Thanks Ed!

http://www.top-5000.nl/authors/rebel/chess840.htm

I cannot wait for the Passed Pawn stuff. I think that will land him a lobster and steak!

Mark
by mjlef
Mon Jun 11, 2007 7:23 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: what is the current slope of the curve
Replies: 5
Views: 3554

Re: what is the current slope of the curve

The "sahpe of the curve" is a lot harder to judge now. Programs using Late Move Reductions, Null Move Reductions and other pruning typically have a branching factor of about 2 versus something like 6 for a traditional program. Of course these reductions mean the length of the tree varies a lot, and ...
by mjlef
Mon Jun 11, 2007 7:19 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Performance Variance due to C++
Replies: 7
Views: 4405

Re: Performance Variance due to C++

I noticed the other day that if I load two copies of an identical program into the same GUI, the program sometiems take different amounts of memory. I am not sure why...I do not have them set to different hash table sizes. Maybe there is not enough physical memory left and one process gets less memo...
by mjlef
Sun Jun 10, 2007 7:34 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Revisiting Check Extensions
Replies: 18
Views: 10758

Re: Revisiting Check Extensions

Basing this on material has a couple of dangers: (1) if you don't extend checks that lose material, what happens to you on positions like WAC 141 where the key move tosses the queen for no apparent gain? I see no reason why people here keep giving single exceptional positions when new ideas are pre...
by mjlef
Sat Jun 09, 2007 8:04 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Revisiting Check Extensions
Replies: 18
Views: 10758

Re: Revisiting Check Extensions

Basing this on material has a couple of dangers: (1) if you don't extend checks that lose material, what happens to you on positions like WAC 141 where the key move tosses the queen for no apparent gain? I see no reason why people here keep giving single exceptional positions when new ideas are pre...
by mjlef
Fri Jun 08, 2007 7:17 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Performance Variance due to C++
Replies: 7
Views: 4405

Re: Performance Variance due to C++

One suggestion. Swap the order of the programs in whatever GUI you are using and see if the scores move with the specific program, or if it stay with the order of the programs. Maybe your GUI does something odd in terms of priorities fo search threads, or in how it healdes the engines based on who i...
by mjlef
Fri Jun 08, 2007 7:14 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Help Finding X
Replies: 9
Views: 4832

Re: Help Finding X

Hi Mark, First thing that comes to mind is the 50 move rule. That certainly sets a maximum. Other than that, SCID and the Chessbase database that comes with all their programs. Charles Thanks for the suggestions. Of course, pretty much all programs already have the 50 move rule in them (as does min...
by mjlef
Fri Jun 08, 2007 5:15 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Help Finding X
Replies: 9
Views: 4832

Help Finding X

In the endgame, many positions are hopeless draws which can almost be determined via static analysis, after a certain depth of conversion. For example. lets say we get down to K&R vs K&R. Unless one side has a K and R along the same file or column, apart a bit, the other side can only get a draw (in...
by mjlef
Thu Jun 07, 2007 1:11 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Pro Deo 1.5
Replies: 10
Views: 5973

Re: Pro Deo 1.5

Hmmm... I wonder if that is what all that data is in Rybka? Bonuses for lines it tends to win more in.
by mjlef
Thu Jun 07, 2007 1:05 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Revisiting Check Extensions
Replies: 18
Views: 10758

Re: Revisiting Check Extensions

I tried something like that a long time ago (not extending checks if way ahead in material). I did not such a high margins (8 pawns) though, so that might matter a lot. I did steal Tord's idea of not including chekcs in the qsearch if way ahead in material...I have not idea if it helps, but it makes...