Search found 16819 matches

by bob
Thu Nov 14, 2019 8:53 pm
Forum: Computer Chess Club: General Topics
Topic: Syzygy tbs bug
Replies: 9
Views: 596

Re: Syzygy tbs bug

How can a TB handle that? It simply looks up a position and gives the score. It doesn't know about past game history. That is up to the program to handle. IE if the move is a 3-fold repetition, why bother looking it up in the database? IE in crafty, I check for repetitions first. If found, I return ...
by bob
Fri Nov 08, 2019 5:42 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 18
Views: 1730

Re: Limiting nodes to reduce engine strength

I am still working on getting reliable (within my testing framework) Elo for 2800, 2600, 2400 ... It is not exactly easy. I have not fiddled with extensions and reductions as of yet, because I believe that reducing the NPS far enough will do effectively the same thing. Since I only have a check exte...
by bob
Thu Nov 07, 2019 7:47 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 18
Views: 1730

Re: Limiting nodes to reduce engine strength

This is hard. Where do I find such humans? Certainly not on ICC since so many use computers there. If we had enough tournaments here in Birmingham, I might try that but it would probably cause objections. The 1800 version might well be much stronger against humans, disrupting the 1800-1999 class com...
by bob
Thu Nov 07, 2019 6:12 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 18
Views: 1730

Re: Limiting nodes to reduce engine strength

Not a fan of a depth limit, since they can occasionally be quite "coarse" in terms of time. I have a pretty decent NPS idea in the works. I have normalized on 2800 Elo == 6M nodes per second (on my MacBook). Elo scales down the NPS and introduces evaluation randomness. And it is actually working pre...
by bob
Thu Nov 07, 2019 5:46 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: oldie but goody
Replies: 11
Views: 1174

Re: oldie but goody

I will warn you: they are NOT easy to find. If Fortran only required type declarations for all variables, it would be pretty easy. But with the "implicit" declaration (IE implicit integer a-z) we are pretty much screwed. Each piece will have to be debugged pretty much line by line since it won't pro...
by bob
Wed Nov 06, 2019 10:40 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: oldie but goody
Replies: 11
Views: 1174

Re: oldie but goody

They have the number wrong. I have a couple of boxes of junk I kept (for unknown reasons). I actually have the sigma 9 reference manual. On page 167 it says that the "add immediate" instruction (add the 17 bit address field directly to the indicated register destination (R0 - R15). I did not really ...
by bob
Wed Nov 06, 2019 7:51 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: oldie but goody
Replies: 11
Views: 1174

Re: oldie but goody

I think that number is wrong. Sounds more like a sigma 6/7. IIRC, the sigma 9 had a .73 microsecond clock, which would translate to about 1.3MIPS. If every instruction referenced memory it could not run that fast, but it was pretty fast for the day. Today my Apple watch has more computing power. :)
by bob
Wed Nov 06, 2019 5:42 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: oldie but goody
Replies: 11
Views: 1174

Re: oldie but goody

I would be interested, too, Dr. Hyatt. I have one of Jim Ablett's Cray Blitz Windows compiles (running from the command prompt) from 2008. The included source was also written in Fortran. I assume this is your code as well. Yes it was. But for the CB source it was NOT scanned in via OCR. I actually...
by bob
Tue Nov 05, 2019 3:59 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: oldie but goody
Replies: 11
Views: 1174

oldie but goody

I don't know if I have ever released this, but I was looking through old files and ran across a REALLY old version of my chess program. WAY before it had the "Cray" in its name. This is version 6.9, dated 1977, which sounds right. Right after the WCCC that year, I decided to get rid of the highly se...
by bob
Mon Nov 04, 2019 2:45 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Limiting nodes to reduce engine strength
Replies: 18
Views: 1730

Re: Limiting nodes to reduce engine strength

Been playing with this for a couple of days. Using the OPs idea of dynamically adjusting the NPS, plus my original approach of randomizing the evaluation, I have gotten something that works. Nowhere near perfect yet, and calibrating it is a bit difficult. But I took a couple of open-source programs,...