Hi Sage-Devel (cc: Markus), After emailing with Markus Hohenwarter -- director of Geogebra -- and looking around at the code, I get the impression that the Geogebra group is very well meaning and a great group of people doing some wonderful things in math education. Unfortunately, it appears they are also possibly violating the GPL in order to ensure complete control over their project (which is something the GPL doesn't allow). I want to emphasize that I think they are well meaning and aren't doing this out of any sort of evil intentions, and of course I strongly applaud their putting a lot of effort into open source math software and math education, much of it likely voluntary.
I think that Geogebra has to be GPL'd because it fundamentally depends on the java version of the GPL'd yacas library (yacas = yet another computer algebra system). On the other hand, it seems that the Geogebra folks purposely criple Geogebra by making the build system, language files (?), and documentation all non-GPL compatible. As a result it seems that one can't use Geogebra under the terms of the GPL. This might be a violation of the GPL. (Note that I wrote "seems" and "might" in several places above, since I'm not really certain of anything. I could be just plain wrong!) So I don't think (optional) integration or support of Geogebra from Sage is a wise move right now. I very much hope the situation with Geogebra changes asap. I.e., in my opinion, the Geogebra group should either make the Geogebra distribution fully GPL'd or they should replace YACAS by another non-GPL'd component and switch to a license other than the GPL that allows them to restrict redistribution in the ways they see fit. -- William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---