commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Phil Steitz <stei...@yahoo.com>
Subject Re: [math] matters of copyright
Date Mon, 02 Jun 2003 23:41:31 GMT
--- robert burrell donkin <robertburrelldonkin@blueyonder.co.uk> wrote:
> hi tim
> 
> let me begin by saying that i think you did the right thing and handled 
> things pretty well.  i hope that brent will appreciate that commons-math 
> is still just ramping up and we're probably going to have to discuss and 
> sort things out a lot more during this stage.
> 
> there is a list which committers can post questions like this (licensing@a
> pache.org) but i would suggest that we take a little time to formulate the 
> right question. we would probably be better advised to have a general 
> policy we can check (maybe using this specific as an example) rather than 
> asking every time this question comes up. we can then make sure that 
> developers understand and follow this policy.
> 
> what follows is all IMHO and with the usual disclaimer about me not being 
> a lawyer.
> 
> i've taken a quick look at the reference (to numeric recipes) given and 
> the intention seems pretty clear. the numeric recipes book is a manual for 
> commercially licensed software. no derivative works of implementations 
> found there can be be created without infringing their copyright. that is 
> very clear.
> 
> i guess that providing anything about translations to other languages 
> would be difficult but i still think that it's very dubious ethically to 
> create ports from the code found in that book. i would not support the 
> addition of any code ported from the code found there.
> 
> it seems to me that brent is assuring us that he went back to the 
> mathematical basis of the algorithm and started from that. a clean 
> implementation based on the mathematics should not infringe the copyright 
> nor is it ethically dubious (providing that the correct credits for the 
> original mathematics are provided if that's possible). what we need to 
> think about is how we can demonstrate this to everybody's satisfaction. 
> the openness of the ASF is one of it's great strengths and there should be 
> some way we can show the right way to develop new implementations. (of 
> course, we need to work out what that is first ;)

>From Brent's notes on the gamma function implementations, I at least am
convinced that his implementation was developed from the math, not the NR
algorithm or code.  The dodgy bit is that someone else who did the same
derivation and ended up with a similar implementation (e.g. NR) might claim
ownership of the algorithm itself.  This is why the limitation expressed in the
NR copyright statement is important.
> 
> i believe that providing new implementation from the basic mathematics is 
> what commons-math should do. there is no real reason why we should start 
> from existing code. if we can't, then maybe that's a sign that we're 
> moving away from our aims.

The one exception to this is obviously existing code that is owned by the
contributor.  Even in this case, however, refactoring will usually be required
(certainly has been for me :-)).
> 
> commons-maths needs to develop it's own niche somewhere between the 
> academic and the commercial worlds. i'm very happy that people are talking 
> to the ACM and COLT but any progress in those directions would IMHO 
> probably mean thinking about something larger (maybe a commons.apache.org 
> subproject so that people could think about porting to other languages).

To me, at least, the primary objective of commons-math is to provide natural
and performant *Java* implementations of basic math capabilities.  This fits in
jakarta-commons -- a "portable" compendium of numerical algorithms does not.
Just my HO.

Phil


> 
> - robert
> 
> On Monday, June 2, 2003, at 07:30 PM, Tim O'Brien wrote:
> 
> > Brent, thanks for the detailed responses, and if it makes you feel any
> > better my handwriting is much, much worse.
> >
> > I put a question out to people who can make more official statements
> > about licensing, and I want to see if I can get an official opinion
> > about some of these issues before re-adding Gamma.java and referencing
> > NR.
> >
> > Also, I want to make it clear that I don't think anyone has violated
> > copyright, I just want to tread carefully - best to err on the side of
> > caution.
> >
> > Tim
> >
> >
> > On Mon, 2003-06-02 at 13:12, brent@worden.org wrote:
> >>>> 2) regularizedGammaP is derived using (6.2.1) and (6.2.5) from NR.
> >>> I also
> >>>> have hand-written notes on how I derived the implementation from
> >>> those
> >>>> formulas that I would be happy to provide for your viewing.
> >>
> >> Here are my aforementioned notes:
> >> http://www.brent.worden.org/math/page.1.tif
> >> http://www.brent.worden.org/math/page.2.tif
> >>
> >> And before anyone says a thing, these are not the result of chicken
> >> scratches.  Sadly, it is my handwritting.
> >>
> >> Brent Worden
> >> http://www.brent.worden.org/
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
> >> For additional commands, e-mail: commons-dev-help@jakarta.apache.org
> >>
> >
> >
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
> > For additional commands, e-mail: commons-dev-help@jakarta.apache.org
> >
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
> For additional commands, e-mail: commons-dev-help@jakarta.apache.org
> 



__________________________________
Do you Yahoo!?
Yahoo! Calendar - Free online calendar with sync to Outlook(TM).
http://calendar.yahoo.com

---------------------------------------------------------------------
To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
For additional commands, e-mail: commons-dev-help@jakarta.apache.org


Mime
View raw message