Re: [Help-gsl] MT19937 licensing in GSL RNG and beyond

[Brian Gough]

At Tue, 20 Mar 2007 17:19:54 +1100,
Paul C. Leopardi wrote:
> In contrast, the author of the MT code in GSL RNG (Brian Gough)
> released the code in 1998 under the LGPL, and then changed the
> license from LGPL to GPL.  See eg. gsl-1.8/rng/mt.c
> 
> 1. How was it possible to release the GSL RNG version of MT under
> the LGPL in 1998, when the license for the Japanese version was not
> made more liberal until 2001? Did Brian Gough need to ask Makoto
> Matsumoto and Takuji Nishimura for special permission needed to do
> this? Or was licensing under LGPL possible because the GSL RNG
> version was a separate and independent implementation of the
> algorithm, and thus not subject to the copyright of the Japanese
> code?

In 1998 the original Japanese version was actually licensed under the
LGPL, so none of these problems occurred.  

-- 
Brian Gough

Network Theory Ltd,
Publishing Free Software Manuals --- http://www.network-theory.co.uk/