Search found 16818 matches

by bob
Thu Jun 13, 2019 11:38 pm
Forum: Computer Chess Club: General Topics
Topic: WCCC vs TCEC Chess Engine Competitions..
Replies: 33
Views: 5189

Re: WCCC vs TCEC Chess Engine Competitions..

If I had to post one complaint about the ICGA (ICCA at the time) it would be that they catered too much to the commercial programs/programmers. One example: Ken Thompson and I proposed, in the late 70's, that the ACM/ICCA tournaments should move to an automatic interface mode. There were several rea...
by bob
Wed Jun 12, 2019 2:24 am
Forum: Computer Chess Club: General Topics
Topic: WCCC vs TCEC Chess Engine Competitions..
Replies: 33
Views: 5189

Re: WCCC vs TCEC Chess Engine Competitions..

I would like to add something here, since "some" are trying to keep various types of "bitterness" alive and well. Computer chess went through three really distinct phases. Phase 1 started in 1970 and continued into the early 90's, where we had annual ACM computer chess tournaments (and every three y...
by bob
Wed Jun 12, 2019 1:30 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: max number of pseudo legal move
Replies: 29
Views: 5178

Re: max number of pseudo legal move

A LONG time ago, I decided to make this particular question a non issue. I use a big array (vector). I have another vector last[ply]. The idea is then that for all plies, last[ply] points one past the last move for the current ply. If you want to iterate over the complete move list for ply=4, you do...
by bob
Wed Jun 05, 2019 3:27 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: strategies for finding slowdows in lazy smp
Replies: 26
Views: 4753

Re: strategies for finding slowdows in lazy smp

Good observation. Either this is (a) total-NPS divided by threads or else (b) it is broken. About all NPS is useful for is to detect architectural issues, such as cache thrashing / false sharing or bandwidth issues, processor throttling due to heat, memory bottlenecks, etc. The number of cores is ge...
by bob
Tue May 07, 2019 4:07 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: (possible stupid question) asymmetrical search
Replies: 5
Views: 1075

Re: (possible stupid question) asymmetrical search

Richard Lang did this in the old Chess Genius engines. As but one example, you can make it harder to make a tactical mistake yourself, using caution, but then make it harder to find wild tactical shots since you don't do the same types of things for both sides. Idea made sense back in the days of li...
by bob
Tue May 07, 2019 4:00 am
Forum: Computer Chess Club: General Topics
Topic: Authors of chess engines getting crushed by their creations
Replies: 17
Views: 2680

Re: Authors of chess engines getting crushed by their creations

Crap. Meant to write "have not been gone, am not coming back." That is, I never left. :) just haven't had much to say. It's amazing how busy life gets when you own a boat, an RV, automobiles, house, have family, travel, most everything is "do it yourself" and so forth. Sometimes I am busier now than...
by bob
Sun May 05, 2019 10:26 pm
Forum: Computer Chess Club: General Topics
Topic: Authors of chess engines getting crushed by their creations
Replies: 17
Views: 2680

Re: Authors of chess engines getting crushed by their creations

Wasn't intending to make this anything about me. However, for the record, my first chess program played its first move in very late 1968. I was a computer science major at the University of Southern Mississippi and star trek / spock / computer chess had already caught my interest. There was practica...
by bob
Sat May 04, 2019 5:41 pm
Forum: Computer Chess Club: General Topics
Topic: Authors of chess engines getting crushed by their creations
Replies: 17
Views: 2680

Re: Authors of chess engines getting crushed by their creations

Not sure this is "news". In the early 80's, I might win one out of 100 games against Cray Blitz, yet our ratings were pretty equal in terms of USCF. 5 years later, that was zero out of 100. Been that way all the way through current Crafty. It is really easy to develop an engine that beats you trivia...
by bob
Sat Nov 24, 2018 3:04 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: adding an existing key to the hashtable
Replies: 9
Views: 1774

Re: adding an existing key to the hashtable

Here's the reason for overwriting. Apparently whatever is there was not good enough to terminate the search at the start of this position, so what's the point of saving something that didn't work when you now have something that is correct and useful?? IE exactly what HGM said but with fewer words.....
by bob
Fri Nov 16, 2018 4:47 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Any Fortran coder ?
Replies: 26
Views: 4544

Re: Any Fortran coder ?

Recursion has worked for a long time now. One thing to avoid is a 2d array, use a 1d vector instead. Otherwise every array access ends up with an integer multiply buried in the middle of the address calculation. Otherwise it will work fine. The language is a bit of a mismatch for chess but I used it...