These are chat archives for SHTOOLS/SHTOOLS

2nd
Sep 2016
Mark Wieczorek
@MarkWieczorek
Sep 02 2016 08:34
Someone asked a while ago about wether the revised-BSD license is compatible with the FFTW GNU GPL. As far as I can tell, this is not a problem. The following is taken from the gnu web site.

Modified BSD license
This is the original BSD license, modified by removal of the advertising clause. It is a lax, permissive non-copyleft free software license, compatible with the GNU GPL.

This license is sometimes referred to as the 3-clause BSD license.

The modified BSD license is not bad, as lax permissive licenses go, though the Apache 2.0 license is preferable. However, it is risky to recommend use of “the BSD license”, even for special cases such as small programs, because confusion could easily occur and lead to use of the flawed original BSD license. To avoid this risk, you can suggest the X11 license instead. The X11 license and the modified BSD license are more or less equivalent.

If there is a good reason to change from revised-bsd to something else, I'm open to changing. Just let me know why.
MMesch
@MMesch
Sep 02 2016 09:47
I think GPL requires that derived products are GPL as well. Not at all sure ...
Mark Wieczorek
@MarkWieczorek
Sep 02 2016 10:16
well, it is "compatible" with gpl. I'll look more to see if there are any other requirements. I'm looking into potential problems with using Numerical Recipes algorithms now...
In the work case, we might need to remove the Random routines, which are used in the tests. Calculating the Gauss-Legendre quadrature weights also uses an NR algorithm, but this is pretty standard stuff so I am less worried about that.

Also, I'm considering removing these routines from the python module (but not Fortran)

other.EigValSym
other.RandomGaussian
other.EigValVecSym
other.RandomN
other.EigValVecSymTri
other.PreGLQ

I suspect that these are probably implemented in numpy or scipy somewhere.

Mark Wieczorek
@MarkWieczorek
Sep 02 2016 10:36

We are ok with revised-bsd and fftw:

What does it mean to say a license is “compatible with the GPL?”

It means that the other license and the GNU GPL are compatible; you can combine code released under the other license with code released under the GNU GPL in one larger program.

MMesch
@MMesch
Sep 02 2016 11:06
ok perfect