RE: [Help-gsl] Source code for HiCalc / breah of GPL for GSL

[Li, Timothy - BLS]

Dr. Kirkby:

Just supply some thoughts after your reply.

I sincerely think HiCalc can live without GSL -- not to discredit GSL.
In fact HiCalc can run even faster without it. The matrix inversion in
GSL, for example taken care of general numeric that HiCalc doesn't need
slows down the calculation quite a bit for small matrices. For a
calculator that will not run into the problem of sparse, or huge
dimensional matrix problems, GSL is an overkill. Singularity or
near-singularity problem is not a problem now a days to handle neither.
Just do a Google search, there are numerous ready-to-use free codes, now
this is for the non-specialists. For specialists, though they are not
needed at this calculator complexity level, there are simple and clear
expositions available too. To get a start, for example, the book
"Statistical Computing" handles that problem in pages. 

I think GSL serves its best as a free public medium, as the numerous
numerical algorithms the GSL is coded upon.


Dr. Timothy Li 

-----Original Message-----
From: Dr. David Kirkby [mailto:address@hidden 
Sent: Tuesday, July 11, 2006 3:04 PM
To: Li, Timothy - BLS
Cc: Brian Gough; address@hidden
Subject: Re: [Help-gsl] Source code for HiCalc / breah of GPL for GSL

Li, Timothy - BLS wrote:
> -- Just a comment --
> 
> I suspect HiCalc will drop using the GSL and implement numerical 
> algorithms by themselves.

That would not get them out of their responsibilities under the GPL. The
source code for the *current* version should still be released. If they
choose to use a different library for a later release that is up to
them.

> Inverting matrices is not a challenge to even an average programmer 
> today,

Easy to go wrong if the matrix is close to singular.

> but given out their source code would be too much of a financial loss 
> to them. I don't see any function in HiCalc can not live without GSL.

But I can't see how they can (or rater should) avoid giving the source. 
The GPL is clear on that and its clear they are using a GPL'ed library.

They have obviously profited for some time using the work of others so I
don't see why they should continue to withhold the source so they can
continue to profit.

If they provide an extra service (support for example), then that is a
different matter. But the source should still be released.

To be fair, they have not declined to release the source. I have asked
them about it today, but that was only a few hours ago.

Of course there is the point the contravention is likely to have been
unintentional. But you can crash your car into someone elses car
unintentionally - it does not free you from your responsibilities to pay
them for the repair.

In this case it seems to me people are loosing out since the source is
not public.

> By listing GSL on HiCalc about box in a way promotes the popularity of

> GSL, why not just leave it the way it is.

I personally can't agree with you. It would make a mockery of the GPL to
advertise on software the fact it uses the GSL and not release the
source.

--
Dr. David Kirkby