Fabien's open letter to the community

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Rolf
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Re: Fabien's open letter to the community

Post by Rolf » Thu Jan 27, 2011 5:36 pm

Roger Brown wrote:
This is typical for Rolf so why get excited by it?
Perhaps you could explain what Fabien could have meant with

"I just want to clarify a few things. Sorry if that's old but there is some misunderstanding I need to fix, and I found out only yesterday. Bear in mind that I am mostly unaware of what has happened for five years though."
-Popper and Lakatos are good but I'm stuck on Leibowitz

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Watchman
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Re: Fabien's open letter to the community

Post by Watchman » Thu Jan 27, 2011 5:49 pm

El Gringo wrote: BTW, i checked about fabien, He lives in Lille (so that's correct) (Rijsel for the dutch people) and he's in the Lille Go club. He is the tresholder there.
I only lives 50km from Lille so i could check for all those who think it's a fake one....

Best
Johan
Well Johan that would be nice but...

For all the naysayers and non-believers, skeptics and scoffers: we would have to send someone out to check that you are not fake too. :lol:
playjunior wrote: Who wants to bet how long will it take until someone accuses Fabien for not being "a real person"? ;)
It was "just a matter of time" before someone raised that question. :lol: I think I was in the "20s" (pages of this thread) before I thought soon someone would soon express their doubts. :D I am somewhat relieved to see it done in jest.

I am surprised a poll has not been started on this very topic. :lol:
Rob O. / Watchman

Damir
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Re: Fabien's open letter to the community

Post by Damir » Thu Jan 27, 2011 6:00 pm

Rob,

Judging from your picture, you don't seem to be that real either... :lol:

bob
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Re: Fabien's open letter to the community

Post by bob » Thu Jan 27, 2011 6:07 pm

Gian-Carlo Pascutto wrote:
Matthias Gemuh wrote:
Dann Corbit wrote:
bob wrote: (2) I did the mailbox-to-bitboard translation with Crafty. It only affects a part of the code. Search is unchanged. Move ordering is unchanged. Several other things are completely board representation independent.
Crafty is a giant machine with nearly 40K lines of code. At ten lines per hour and $100/hour that would translate to $400,000 worth of work. ...
"ten lines per hour" ?

You translate huge chunks of code almost as fast as you can type. Why should average speed drop to "ten lines per hour" ?
You can average faster than that, then hit a construct that doesn't directly translate.

Then it won't be so fast.
Probably not. But I did the _entire_ conversion from Cray Blitz to Crafty during December 1994. I started right after the ACM computer chess tournament in late November, and had the thing playing on ICC by the end of December.

I've been writing software all my life and can't recall a period of time where I could only produce 10 lines of code an hour, unless you back up to the front of the project and include requirements analysis, specifications, and all of that. For a translation from mailbox to bitboard, you just start at the coding stage and go.

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Re: Fabien's open letter to the community

Post by bob » Thu Jan 27, 2011 6:16 pm

Don wrote:
bob wrote:
Dann Corbit wrote:
Don wrote:
Houdini wrote:
Don wrote:I think you are correct. I personally AM a fan of rewrites but I think there are many chess authors that don't ever rewrite, or have only done so once in years.
Rewriting for the sake of rewriting doesn't serve any purpose at all.
Software with a good architecture will survive many years and many changes.

Robert
I don't rewrite just for the sake of it.

Don
Typical reasons for rewriting:
1. Change of language (e.g. C to C++)
2. Change of underlying data structures (e.g. mailbox to bitboard)
3. Increased programming ability (every decade, my programming skills increase quite a bit, so the code I wrote 20 years ago will benefit considerably from a rewrite).
4. Lost code (yes, it does happen -- I have sent code back to chess authors who lost their original code and who had also sent their code to me on several occasions, for instance).
I don't agree with those.

(1) can be solved via translation. A good program can be translated to a new language without rewriting a thing...
(2) I did the mailbox-to-bitboard translation with Crafty. It only affects a part of the code. Search is unchanged. Move ordering is unchanged. Several other things are completely board representation independent.
(3) I don't think is that common. One does not rewrite _everything_ just because they are a better programmer now than 10 years ago. you might rewrite _parts_. But not the whole thing. That is a huge waste of time and effort.
(4) Never had that happen to the current version of code since I always keep duplicates and backups scattered around.
Bob,

I think there is a fundamental misunderstanding about what a "rewrite" is. You are approaching it as some kind of direct translation.
Exactly the opposite. I do _not_ consider a "translation" to be a rewrite. Yet that is what is being claimed in this thread. Taking a mailbox program and modifying it to use bitboards is _not_ a "complete rewrite". The new bitboard program is a clear derivative of the original mailbox program. Whether you convert from one data structure to another, one language to another, none of that matters. The two programs are "relatives". yes, I might call the changed program a "new version". That is generally where I change the major version number in Crafty, when I introduce some gross incompatibility with old data structures, or a different book format, etc... But it is not a "rewrite"


When I use the term "rewrite" I'm talking about making a completely different program. The new program does not play the same, it's not just a simple port of one data structure or language to another.
I don't quite call that a rewrite either. One can change 10 lines and it won't play the same. I call a "rewrite" what you do when you throw out the old, and start from scratch and write something new. Which does happen from time to time. Such as in the creation of much of the GNU unix software where they could not copy the original AT&T code for various commands and had to write from scratch to avoid the license issue.


I would not bother to "rewrite" a program if that was the only point. I would only do it to take advantage of a different data structure that allowed me to do things differently and better.

Some of your reasons for disagreeing with Dann did not make any sense. For example just because you have not recently lost your source code, how does this refute the notion that losing source code is a reason for rewriting? I don't understand this.

How many have actually lost their source code, _completely_. So that they had to start from scratch, as opposed to backing up to the last good backup and trying to reconstruct the changes? Which would be more efficient. Yes, if a meteor hit Campbell Hall while my laptop is there, I might have to do a complete rewrite since that could potentially wipe everything out, our data center, my office box, our backups and my laptop. But how likely? Using that as a potential reason makes little sense.

I also don't see how changing the data structure is not a typical reason for rewriting. I think it's VERY typical. In fact I have rewritten programs for this very reason. Note that I said rewritten, not "translated."

Don
I don't believe you "rewrote". The word "rewrite" means to take something that has been written from scratch previously, and repeat (re) that process again. Who throws everything out? We are on Crafty version 23.5. Nowhere over that 15 year period of 23 major versions was everything thrown out and rewritten. Maybe a small piece here, or a small piece there. But would you want to see all 23 of those versions entered into a chess tournament together if I try to call them 23 different and non-derivative programs? I wouldn't. And that is what we are talking about here. R1 has fruit code, clearly. I do not believe that subsequent versions do not. It would be too big a waste of time to rewrite every 2 years. It would take me at least a year to get back to where I am, if not more... That's not efficient.

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Re: Fabien's open letter to the community

Post by bob » Thu Jan 27, 2011 6:19 pm

Rolf wrote:
Xann wrote: I refine:
Fabien.
Hi Fabien, please let me ask some questions:

1 At the time when you had contact with the computerchess scene for the last time, was there any form of contact either via direct talking or via email or postal messages betweenyou and Vas? If yes, was this about a sort of agreement from your side if Vas would have wanted to use some of your ideas and or code - since at the time you might have signaled your wish to let it all behind and leave the scene?
He has already answered that and said he has had _no_ contact with Vas whatsoever.


2 Did you imply with your first message few days ago that you really had no contact nor knowledge of anything from CC for about 5 years until "yesterday" as you wrote when you took a look for the first time (in 5 years)? Where did you live then? Top secret military institution, please could you give us some details about that, because it looks so suspicious.

3 Talking about the real reality. Do you see a difference in the open and known reputation of Vasik Rajlich, who was with you attenting some World Championships and totally obsure figures like the strawmen behind the "hippo" cosa and now some hidden Houdini magician?? When you stepped into it yesterday or a day before, did you consider the probability for some legal issues from that aspect? Are you familiar with the law problem especially in Russia considering the Strelkas?


Since I'm not at all an expert in CC I must tell you that it would be strange if I would now discuss anything with you. My interest came from psychology. I wished that I could inspire a debate about the given points. Thanks for now.

bob
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Re: Fabien's open letter to the community

Post by bob » Thu Jan 27, 2011 6:21 pm

Rolf wrote:
Roger Brown wrote:
This is typical for Rolf so why get excited by it?
Perhaps you could explain what Fabien could have meant with

"I just want to clarify a few things. Sorry if that's old but there is some misunderstanding I need to fix, and I found out only yesterday. Bear in mind that I am mostly unaware of what has happened for five years though."
What is there to interpret? It seems perfectly clear and concise...

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AdminX
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Re: Fabien's open letter to the community

Post by AdminX » Thu Jan 27, 2011 6:30 pm

bob wrote:
Rolf wrote:
Roger Brown wrote:
This is typical for Rolf so why get excited by it?
Perhaps you could explain what Fabien could have meant with

"I just want to clarify a few things. Sorry if that's old but there is some misunderstanding I need to fix, and I found out only yesterday. Bear in mind that I am mostly unaware of what has happened for five years though."
What is there to interpret? It seems perfectly clear and concise...
Which might explain why ....
Rolf wrote:
"Now I read that Fabien as the owner of Fruit didnt take offense by Rybka code."
http://talkchess.com/forum/viewtopic.ph ... 426#210426
"Good decisions come from experience, and experience comes from bad decisions."
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Matthias Gemuh
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Re: Fabien's open letter to the community

Post by Matthias Gemuh » Thu Jan 27, 2011 6:54 pm

El Gringo wrote:
Damir wrote:
Rolf wrote:
Xann wrote: I refine:
Fabien.
Hi Fabien, please let me ask some questions:

1 At the time when you had contact with the computerchess scene for the last time, was there any form of contact either via direct talking or via ... I wished that I could inspire a debate about the given points. Thanks for now.
Your first post here and with such disrespect and arrogance. IMO, I think mods should ban you and not allow you to come back here.
Fully Agreed,

BTW, i checked about fabien, He lives in Lille (so that's correct) (Rijsel for the dutch people) and he's in the Lille Go club. He is the tresholder there.
I only lives 50km from Lille so i could check for all those who think it's a fake one....

Best
Johan
I suggest that Rolf should restrict himself to reading without posting in CCC.

Matthias.
My engine was quite strong till I added knowledge to it.
http://www.chess.hylogic.de

Gerd Isenberg
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Re: Fabien's open letter to the community

Post by Gerd Isenberg » Thu Jan 27, 2011 7:06 pm

bob wrote:For a translation from mailbox to bitboard, you just start at the coding stage and go.
The mapping from mailbox to bitboards seems surjective ;-)

For me, vice versa from bitboards to mailbox would be almost impossible. SIMD fill stuff everywhere, pawn-spans, pawn attack-spans, disjoint direction-wise SIMD kogge-stone fills rather than piecewise attack generation, zillions of patterns with set-wise operations, white to move always by color-flipping the quad-bitboard in make, etc..

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