Search found 4341 matches

by syzygy
Sat Nov 17, 2012 11:33 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence - Check Evaluation and Depth Control
Replies: 56
Views: 10467

Re: Quiescence - Check Evaluation and Depth Control

Do you check for repetition when moving out of check in qsearch? That's a bizarre idea. Do you really get some significant node reduction from that ? In general, I mean, not this position in particular. My intuition tells me that the cases where it will be used are so rare, that it doesn't make sen...
by syzygy
Sat Nov 17, 2012 12:17 am
Forum: Computer Chess Club: General Topics
Topic: Rybka 4.1 is still unbeatable in some positions
Replies: 8
Views: 1673

Re: Rybka 4.1 is still unbeatable in some positions

Is it possible to run perft(21) or similar to get the truth in this one?? My guess is the sun will turn into a white dwarf before the perft(21) is finished. Luckily a regular full-width 19-ply alpha-beta search suffices to get to this truth. And it can be done with a nullwindow and without qsearch ...
by syzygy
Fri Nov 16, 2012 12:38 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence - Check Evaluation and Depth Control
Replies: 56
Views: 10467

Re: Quiescence - Check Evaluation and Depth Control

Jan Brouwer wrote:Note that the 24M moves was for a 1 ply search.

So I added the possibility to do a quiescence search only, the result: 24 M nodes :( (and a mate score, I examine all checks in first ply of quiescence search)

Some investigation is in order...
Do you do underpromotions in the qsearch?
by syzygy
Thu Nov 15, 2012 5:20 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence - Check Evaluation and Depth Control
Replies: 56
Views: 10467

Re: Quiescence - Check Evaluation and Depth Control

I decided to fix this qsearch explosion problem by introducing a depth limit. Basically when the depth is QS_LIMIT, we don't call qsearch() recursively, and return eval + SEE instead. This will make the implementation of the hash table a bit trickier. The depth that I'll have to enter in the hash e...
by syzygy
Thu Nov 15, 2012 12:28 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about perft, what is the proper way of doing it?
Replies: 4
Views: 1520

Re: about perft, what is the proper way of doing it?

I saw that some peoples does the action of move/undo of the last depth and some people just count the number of valid move of the last depth without doing them. nodes/sec are day and night between the two what is the proper/correct way? Do what you like? There is no official perft competition with ...
by syzygy
Wed Nov 14, 2012 8:58 pm
Forum: Computer Chess Club: General Topics
Topic: Houdini's facebook page.........
Replies: 46
Views: 9036

Re: Houdini's facebook page.........

Dr.Wael Deeb wrote:I am just trying to tell you that it's not normal to manipulate your facebook page without an obvious reason........
You feel competent on judging what is normal?

It's fine that you don't like him, but keep it to yourself and don't keep boring us with it.
by syzygy
Wed Nov 14, 2012 8:18 pm
Forum: Computer Chess Club: General Topics
Topic: Houdini's facebook page.........
Replies: 46
Views: 9036

Re: Houdini's facebook page.........

Soon,very soon,your Houdini will be overtaken Mr.telescope.... The impact will hit you from a totally unexcpected direction....... I'll be there to watch you fall hard regards, Dr.D ...it's about how hard YOU can hit and can keep hitting again the same person, over and over again.... you really are...
by syzygy
Tue Nov 13, 2012 7:32 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence - Check Evaluation and Depth Control
Replies: 56
Views: 10467

Re: Quiescence - Check Evaluation and Depth Control

Of course it goes too far for someone who posted a few beginner questions to really go into details, yet i want to post the small remark that if you extend check giving moves in mainsearch rather than check evasions, that you will search in general more nodes. The simple insight to see why already ...
by syzygy
Tue Nov 13, 2012 1:59 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: C++ optimizations
Replies: 32
Views: 8707

Re: C++ optimizations

Profiling would shed light. With which tools ? Instrumented profilers like gprof mostly measure the impact of the added instrumenting code and give numbers so far from any reality that they mean nothing. Profile new and old and look at the difference. What's the meaning of the difference of two wro...
by syzygy
Mon Nov 12, 2012 11:37 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence - Check Evaluation and Depth Control
Replies: 56
Views: 10467

Re: Quiescence - Check Evaluation and Depth Control

I have not had any time yet to work on this further but I understand what you are writing :). I will continue with this and enhance it more so that all ???xQ moves are moved frontwards (MVV) and those moves will be ordered based on ??? (LVA); repeat this for all lesser MVV and so on. To do that, ju...