Fabien's open letter to the community

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Christopher Conkie
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Re: Fabien's open letter to the community

Post by Christopher Conkie » Wed Jan 26, 2011 1:02 am

Graham Banks wrote:
Tom Barrister wrote:.......private Idaho.......
Well at least you have one redeeming feature. You like the B52s. :wink:
Watch out for signs that say "hidden driveways".
Don't let the chlorine in your eyes
Blind you to the awful surprise
That's waitin' for you at
the bottom of the bottomless blue blue blue pool.

He doesn't like the B-52's does he?

Now I'm gonna have to swim round and round like the deadly hand
of a radium clock.......

:)

Chris

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Graham Banks
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Re: Fabien's open letter to the community

Post by Graham Banks » Wed Jan 26, 2011 1:02 am

Ryan Benitez wrote:Computer chess is a unique community in that it has become very grey for reasons I do not understand. I feel that I am in the minority here but I would prefer the FSF clarify what is and is not legal and either shut Rybka down or clear Rybka of GPL violation accusations. I have no personal interest either way and find it unfortunate that this has become such a polarizing issue.
Fabien might find this thread interesting:
http://rybkaforum.net/cgi-bin/rybkaforu ... 7;hl=Fruit
My email addresses:
gbanksnz at gmail.com
gbanksnz at yahoo.co.nz

Dann Corbit
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Re: Fabien's open letter to the community

Post by Dann Corbit » Wed Jan 26, 2011 1:17 am

Ryan Benitez wrote:
Chan Rasjid wrote:
bob wrote:
hgm wrote:
mwyoung wrote:The proof is the author of Fruit himself. "Fabien's open letter to the community". And Vas statement that he claimed that Strelka 2.0 is a clone of Rybka 1.0. This linked Fruit code with Rybka code.
Read it again, then. As many times as it needed to register. He says "legally 'there is no issue". Which means no GPL violation, i.e. no copying of code.

Now I understand of course you take Fabien for an idiot, so that you can ignoe what he writes completely, and just want to use the fact that he says anything at all as a good opprtunity to shoot off your mouth aganst those that you dislike.

But I take Fabien kind of seriously. "No copying of code, but a translation of the algorithm".

So 'poof' goes your 'proof'...
I think you are misinterpreting "translation". Certainly if I translate a book from German to English and sell it as my own, I'll run afoul of copyright laws pretty quickly if the English copy sells well.
This is where most are wrong and HGM right.

The idea of 'derived work' has never been tested yet in any court (internet). Most legal/technical experts interpret 'derived work' in GPL to only include 'copy and paste'. The notions about derived work accepted in general copyright laws do not apply in GPL.

Rasjid
Computer chess is a unique community in that it has become very grey for reasons I do not understand. I feel that I am in the minority here but I would prefer the FSF clarify what is and is not legal and either shut Rybka down or clear Rybka of GPL violation accusations. I have no personal interest either way and find it unfortunate that this has become such a polarizing issue.
FSF cannot own the algorithms unless they patent them.
Hence, if someone reads an algorithm from an FSF program and then writes a function that does the same thing, they have not broken the law.

They can define "derive" in any way that they like, but if they define it in such a way that you cannot learn an algorithm and implenent it, then they have contradicted the existing law and their definition is invalid.

If they want to make a license where it is illegal to read the code and learn from it, then that might be another matter. I don't think it would be enforceable.

Christopher Conkie
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Re: Fabien's open letter to the community

Post by Christopher Conkie » Wed Jan 26, 2011 1:28 am

Graham Banks wrote:
Ryan Benitez wrote:Computer chess is a unique community in that it has become very grey for reasons I do not understand. I feel that I am in the minority here but I would prefer the FSF clarify what is and is not legal and either shut Rybka down or clear Rybka of GPL violation accusations. I have no personal interest either way and find it unfortunate that this has become such a polarizing issue.
Fabien might find this thread interesting:
http://rybkaforum.net/cgi-bin/rybkaforu ... 7;hl=Fruit
Do you think Robert Houdart could explain his source code to Fabian Graham?

Hypothetically of course.....say he just turned up at his house and said hello.

See that telescope he has? It might come in handy looking for another planet to relocate on.......

If there is one programmer I believe in it has to be Fabian. Fruit was like an epiphany for me (and many others i know). It is, and still is, the benchmark of top open source computer chess.

So what planet do you think for Robert?

Surely there is one that supports methane breathers somewhere?

I'm just trying to be helpful of course......dinnae want the wee man tae perish......know what ay mean?

;)

Chris

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M ANSARI
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Re: Fabien's open letter to the community

Post by M ANSARI » Wed Jan 26, 2011 1:43 am

Ryan Benitez wrote:
Chan Rasjid wrote:
bob wrote:
hgm wrote:
mwyoung wrote:The proof is the author of Fruit himself. "Fabien's open letter to the community". And Vas statement that he claimed that Strelka 2.0 is a clone of Rybka 1.0. This linked Fruit code with Rybka code.
Read it again, then. As many times as it needed to register. He says "legally 'there is no issue". Which means no GPL violation, i.e. no copying of code.

Now I understand of course you take Fabien for an idiot, so that you can ignoe what he writes completely, and just want to use the fact that he says anything at all as a good opprtunity to shoot off your mouth aganst those that you dislike.

But I take Fabien kind of seriously. "No copying of code, but a translation of the algorithm".

So 'poof' goes your 'proof'...
I think you are misinterpreting "translation". Certainly if I translate a book from German to English and sell it as my own, I'll run afoul of copyright laws pretty quickly if the English copy sells well.
This is where most are wrong and HGM right.

The idea of 'derived work' has never been tested yet in any court (internet). Most legal/technical experts interpret 'derived work' in GPL to only include 'copy and paste'. The notions about derived work accepted in general copyright laws do not apply in GPL.

Rasjid
Computer chess is a unique community in that it has become very grey for reasons I do not understand. I feel that I am in the minority here but I would prefer the FSF clarify what is and is not legal and either shut Rybka down or clear Rybka of GPL violation accusations. I have no personal interest either way and find it unfortunate that this has become such a polarizing issue.

I agree with that 100%.

Christopher Conkie
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Re: Fabien's open letter to the community

Post by Christopher Conkie » Wed Jan 26, 2011 1:48 am

Christopher Conkie wrote:
Graham Banks wrote:
Ryan Benitez wrote:Computer chess is a unique community in that it has become very grey for reasons I do not understand. I feel that I am in the minority here but I would prefer the FSF clarify what is and is not legal and either shut Rybka down or clear Rybka of GPL violation accusations. I have no personal interest either way and find it unfortunate that this has become such a polarizing issue.
Fabien might find this thread interesting:
http://rybkaforum.net/cgi-bin/rybkaforu ... 7;hl=Fruit
Do you think Robert Houdart could explain his source code to Fabian Graham?

Hypothetically of course.....say he just turned up at his house and said hello.

See that telescope he has? It might come in handy looking for another planet to relocate on.......

If there is one programmer I believe in it has to be Fabian. Fruit was like an epiphany for me (and many others i know). It is, and still is, the benchmark of top open source computer chess.

So what planet do you think for Robert?

Surely there is one that supports methane breathers somewhere?

I'm just trying to be helpful of course......dinnae want the wee man tae perish......know what ay mean?

;)

Chris
Uranus, it's gotta be Uranus....let's launch that "Rocket" now......

;-)

Mark
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Re: Fabien's open letter to the community

Post by Mark » Wed Jan 26, 2011 1:55 am

AdminX wrote:@Uri,

Oh come on please! I find it hard to believe that Vas could create a new number one chess engine from the ground up without ANY reference material at all. What the hell is he a Chess Programing GOD? We are talking about 4 number one chess engines back to back.

Rybka 1

Rybka 2

Rybka 3

Then lost sources and creates ...

Rybka 4

From nothing to start with, I just don't think so.
He wouldn't have started R4 with nothing. After R3 was released, apparently he kept improving the code without saving the old source that matched R3.

SuneF
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Re: Fabien's open letter to the community

Post by SuneF » Wed Jan 26, 2011 2:05 am

bob wrote:
SuneF wrote: This is not all black and white unfortunately, the line must be drawn somewhere. If Rybka is a bitboard version of Fruit written from scratch I don't think it can be called a clone or derivative.
I can't parse that. "version of ... written from scratch" does not compute. If it is "a version of" then it is clearly a derivative. If it was written from scratch, it clearly is not "a version of..."
Suppose you change the basic move structure in a program from e.g. mailbox to bitboard and you do this by starting from scratch.
I would consider this to be a new engine. Changing the basic move structure is a huge undertaking and requires understanding of all the important details of the engine and most likely a total rewrite from scratch.
However as Dan pointed out, if you changed the basic move structure by rewriting the code line by line, then it would be called a derivative no matter if the end result be the same in both cases.
It is impossible for us to look at Strelka now and determine which road was taken, we can only guess. I'm guessing it has been rewritten from scratch and as such is neither a clone or derivative.

I took a brief at look at Fruit v2.1.2 and compared it to Strelka 2.0, there are many differences though.

* Strelka is all bitboard Fruit is not.
* Strelka has multiple specialized search routines for check and null windows, Fruit does not.
* Evaluation and move selection looks quite different.

There are similarities though. For example the hashing schemes (trans_store()) appear somewhat similar. So it might still be possible that Strelka contains some "copied" amount of Fruit code.

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Laskos
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Re: Fabien's open letter to the community

Post by Laskos » Wed Jan 26, 2011 2:46 am

Sven Schüle wrote:
Using Don's similarity test is not valid to prove that two programs are "identical".
Not identical, nothing in physics is identical, self-similarity in this test is not 1. Don's similarity utility is _very_ useful in detecting closely related or extremely closely related engines to the point of an almost pure clone. One has only to check for noise (error margins). His first version was flawed, the last one is perfectly adequate.
It was not intended for this purpose, I may assume that you know that.
No, I don't know that, and I am using it not thinking of how it was intended, I know how it works, and use it to my pleasure.
Surely you can show that two programs _behave_ very similar. And in case of Strelka vs. R1 this is no big surprise, since Strelka was explicitly designed for exact that purpose.

My point remains that Strelka can't be used to conclude anything about Fruit-R1 connections.

Sven
Wrong. You gave examples A --> B. I gave A = B. Now let's take a real world approach.

By all accounts, Vasik's, Uri's, etc. the main part of Strelka 1.8 behaves like Rybka 1.0 Beta. By many accounts Strelka 1.8 is pretty (not very) similar to Fruit 2.1.

Let's say:
Strelka 1.8 is 90% Rybka 1.0 Beta and 10% something else.
Strelka 1.8 is 70% Fruit 2.1 and 30% something else.

Then, in the best case for your denial, Rybka 1.0 Beta is 66.6666% Fruit 2.1. In the worst case for you, Rybka 2.1 is 77.7777% Fruit 2.1, more than Strelka 1.8. It means that if Strelka 1.8 is related to Fruit 2.1, then Rybka 1.0 could be related a little less or a little more than Strelka to Fruit 2.1.

I hope the relation between Rybka 1.0 Beta and Fruit 2.1 is now clearer for you.

Kai

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michiguel
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Re: Fabien's open letter to the community

Post by michiguel » Wed Jan 26, 2011 3:32 am

Laskos wrote:
Sven Schüle wrote:
Using Don's similarity test is not valid to prove that two programs are "identical".
Not identical, nothing in physics is identical, self-similarity in this test is not 1. Don's similarity utility is _very_ useful in detecting closely related or extremely closely related engines to the point of an almost pure clone. One has only to check for noise (error margins). His first version was flawed, the last one is perfectly adequate.
It was not intended for this purpose, I may assume that you know that.
No, I don't know that, and I am using it not thinking of how it was intended, I know how it works, and use it to my pleasure.
Surely you can show that two programs _behave_ very similar. And in case of Strelka vs. R1 this is no big surprise, since Strelka was explicitly designed for exact that purpose.

My point remains that Strelka can't be used to conclude anything about Fruit-R1 connections.

Sven
Wrong. You gave examples A --> B. I gave A = B. Now let's take a real world approach.

By all accounts, Vasik's, Uri's, etc. the main part of Strelka 1.8 behaves like Rybka 1.0 Beta. By many accounts Strelka 1.8 is pretty (not very) similar to Fruit 2.1.
In all the data that I have seen (from different people), Strelka's behavior is very different from Fruit's, or to put it in more accurate terms, is as different as other unrelated engines.

Miguel
Let's say:
Strelka 1.8 is 90% Rybka 1.0 Beta and 10% something else.
Strelka 1.8 is 70% Fruit 2.1 and 30% something else.

Then, in the best case for your denial, Rybka 1.0 Beta is 66.6666% Fruit 2.1. In the worst case for you, Rybka 2.1 is 77.7777% Fruit 2.1, more than Strelka 1.8. It means that if Strelka 1.8 is related to Fruit 2.1, then Rybka 1.0 could be related a little less or a little more than Strelka to Fruit 2.1.

I hope the relation between Rybka 1.0 Beta and Fruit 2.1 is now clearer for you.

Kai

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