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Houdini Multi PV request?

Posted: Wed Jun 16, 2010 12:49 am
by AnthonyTheSage
I don't know how Mr. Houdart did it. But he managed to create the strongest 32 bit single processor engine in the world. On my old P4 2.8ghz Houdini just crushes rybka 4, I'm talking 3 outta 4 games. I just played one 5 minute game that rybka 4 though it was up by .75, Houdini kept maintaining the advantage was only .20, Houdini ended up winning the game. I wish I kept the pgn to post but I was so excited I forgot to save it. Houdini also has a much better attacking style.
Although its obviously the strongest I can't call it the greatest until it has Multi PV. Multi Pv is essential for analysis. I'm not a programmer but I did notice that when some of the other engines add Multi PV, they seem to lose strength, is this simply because of the Multi PV or are the programmers making other changes in the process. I always thought that the multi PV, was only used by the engine when it was analyzing, I don't see how it could suck strength while the engine is playing. I was also wondering if Houdini 1.01 uses the same parameters when it is analyzing as it does when its playing. I know rybka 3 used to use contempt 15 for playing and 0 contemp for analyzing, although there was an option to manually change it. Since this isn't an option in Houdini I'm hoping Houdini analyzes the way it plays.
Anyways, this is a request for Mr. Houdart to add multi PV, and make sure it analyzes the way it plays. Otherwise don't change anything, I love the playing style. Cheers.

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 11:22 am
by Robert Houdart
Anthony,

"If I have seen a little further it is by standing on the shoulders of Giants."

Multi-PV comes at a cost. If you want 3 principal variations, the engine may need to do up to 3 times the work to compute them. A secondary effect is that the hash table will be filled with positions for the second and third PV, most of which are useless for the real PV.
Basically it's like playing on a computer with less computational power and a smaller hash table.

Houdini uses a variable contempt value throughout the game (a bit more in the opening, less in the end game), but currently disables the contempt in analysis mode. I will add an ANALYSIS_CONTEMPT option so you can enable contempt in the analysis mode too.

You can expect real soon Houdini 1.02 which is basically a bug fix release, the multi-PV analysis will be added in Houdini 1.03.

Cheers,
Robert

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 12:00 pm
by BTO7
Robert your engine is awesome ! Look forward to the future releases :)

Regards
BT

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 12:19 pm
by Aloha
Robert Houdart wrote: You can expect real soon Houdini 1.02 which is basically a bug fix release, the multi-PV analysis will be added in Houdini 1.03.
Cheers,
Robert
brilliant news , Robert !! :difus_drinks

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 2:23 pm
by pacifist
Hi Robert,

Congratulations for this awesome engine! I tested the 4 core version and it made very good results vs all other engines. Unfortunately I stopped for the moment because of multiple crashes, mainly when I wasn't there to watch so much time lost. But I wait impatiently the next version, hope it solved this problem :). Good luck with your next versions ;).

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 8:11 pm
by benstoker
Robert Houdart wrote:Anthony,

"If I have seen a little further it is by standing on the shoulders of Giants."

Multi-PV comes at a cost. If you want 3 principal variations, the engine may need to do up to 3 times the work to compute them. A secondary effect is that the hash table will be filled with positions for the second and third PV, most of which are useless for the real PV.
Basically it's like playing on a computer with less computational power and a smaller hash table.

Houdini uses a variable contempt value throughout the game (a bit more in the opening, less in the end game), but currently disables the contempt in analysis mode. I will add an ANALYSIS_CONTEMPT option so you can enable contempt in the analysis mode too.

You can expect real soon Houdini 1.02 which is basically a bug fix release, the multi-PV analysis will be added in Houdini 1.03.

Cheers,
Robert
Mr. Houdart,

Apparently you are not selling Houdini. I suppose you could. But, since you aren't, could you let us know what your opinion is of open source in general and why you presumably are not interested in publishing your work via some open source license such as GPL, which is how Stockfish is published? Thank you. Also, do you have plans to go commercial?

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 8:40 pm
by Charles
benstoker wrote:
Robert Houdart wrote:Anthony,

"If I have seen a little further it is by standing on the shoulders of Giants."

Multi-PV comes at a cost. If you want 3 principal variations, the engine may need to do up to 3 times the work to compute them. A secondary effect is that the hash table will be filled with positions for the second and third PV, most of which are useless for the real PV.
Basically it's like playing on a computer with less computational power and a smaller hash table.

Houdini uses a variable contempt value throughout the game (a bit more in the opening, less in the end game), but currently disables the contempt in analysis mode. I will add an ANALYSIS_CONTEMPT option so you can enable contempt in the analysis mode too.

You can expect real soon Houdini 1.02 which is basically a bug fix release, the multi-PV analysis will be added in Houdini 1.03.

Cheers,
Robert
Mr. Houdart,

Apparently you are not selling Houdini. I suppose you could. But, since you aren't, could you let us know what your opinion is of open source in general and why you presumably are not interested in publishing your work via some open source license such as GPL, which is how Stockfish is published? Thank you. Also, do you have plans to go commercial?
Actually I am curious about something ...
What if I want to keep my software free for now but eventually want to sell it -- If i make my program open source GPL - can I then change this license?

Still, even if I could -- others would see my source so this would not be in my best interest ... So I might have answered the question ,....

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 9:18 pm
by Gerold
Charles wrote:
benstoker wrote:
Robert Houdart wrote:Anthony,

"If I have seen a little further it is by standing on the shoulders of Giants."

Multi-PV comes at a cost. If you want 3 principal variations, the engine may need to do up to 3 times the work to compute them. A secondary effect is that the hash table will be filled with positions for the second and third PV, most of which are useless for the real PV.
Basically it's like playing on a computer with less computational power and a smaller hash table.

Houdini uses a variable contempt value throughout the game (a bit more in the opening, less in the end game), but currently disables the contempt in analysis mode. I will add an ANALYSIS_CONTEMPT option so you can enable contempt in the analysis mode too.

You can expect real soon Houdini 1.02 which is basically a bug fix release, the multi-PV analysis will be added in Houdini 1.03.

Cheers,
Robert
Mr. Houdart,

Apparently you are not selling Houdini. I suppose you could. But, since you aren't, could you let us know what your opinion is of open source in general and why you presumably are not interested in publishing your work via some open source license such as GPL, which is how Stockfish is published? Thank you. Also, do you have plans to go commercial?
Actually I am curious about something ...
What if I want to keep my software free for now but eventually want to sell it -- If i make my program open source GPL - can I then change this license?

Still, even if I could -- others would see my source so this would not be in my best interest ... So I might have answered the question ,....
Hello Robert.
Thanks for the strongest engine i have used. (w32).
You would have to read up on GPL license if you would want to change to commercial.
What would be the advantage of open source GPL.

Best of luck,
Gerold.

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 9:46 pm
by Robert Houdart
Ben,
benstoker wrote:Apparently you are not selling Houdini. I suppose you could. But, since you aren't, could you let us know what your opinion is of open source in general and why you presumably are not interested in publishing your work via some open source license such as GPL, which is how Stockfish is published? Thank you. Also, do you have plans to go commercial?
I have no plans to go commercial, it would remove the fun aspect of the project. Or maybe I'm just not hungry enough :).

I very much admire Stockfish and Crafty for their clear and well documented code, both these project have an important educational value. It would require a major effort to make the Houdini code as well structured and documented as either of these great examples. Publishing the source code to this standard would be very time-consuming and create additional constraints for future developments, which could very well slow down the progress of the chess engine.

In short, both going commercial and open-sourcing the code would create additional constraints of which I'm currently very happy to steer clear.

Robert

Re: Houdini Multi PV request?

Posted: Wed Jun 16, 2010 10:19 pm
by Charles
Gerold wrote:
Charles wrote:
benstoker wrote:
Robert Houdart wrote:Anthony,

"If I have seen a little further it is by standing on the shoulders of Giants."

Multi-PV comes at a cost. If you want 3 principal variations, the engine may need to do up to 3 times the work to compute them. A secondary effect is that the hash table will be filled with positions for the second and third PV, most of which are useless for the real PV.
Basically it's like playing on a computer with less computational power and a smaller hash table.

Houdini uses a variable contempt value throughout the game (a bit more in the opening, less in the end game), but currently disables the contempt in analysis mode. I will add an ANALYSIS_CONTEMPT option so you can enable contempt in the analysis mode too.

You can expect real soon Houdini 1.02 which is basically a bug fix release, the multi-PV analysis will be added in Houdini 1.03.

Cheers,
Robert
Mr. Houdart,

Apparently you are not selling Houdini. I suppose you could. But, since you aren't, could you let us know what your opinion is of open source in general and why you presumably are not interested in publishing your work via some open source license such as GPL, which is how Stockfish is published? Thank you. Also, do you have plans to go commercial?
Actually I am curious about something ...
What if I want to keep my software free for now but eventually want to sell it -- If i make my program open source GPL - can I then change this license?

Still, even if I could -- others would see my source so this would not be in my best interest ... So I might have answered the question ,....
Hello Robert.
Thanks for the strongest engine i have used. (w32).
You would have to read up on GPL license if you would want to change to commercial.
What would be the advantage of open source GPL.

Best of luck,
Gerold.
See reply above ... I am not associated with Robert or any other engine author .. I was just curious above going commercial after GPL.