David Joyner wrote: > On Tue, Dec 29, 2009 at 10:35 PM, Jason Grout > <jason-s...@creativetrax.com> wrote: >> I'm posting this to (1) share what I've learned by reading a lot over >> the last little while, and (2) ask for advice from people that have >> thought a lot about licensing of books and notes. >> >> I'm looking at different licenses for a Sage-enhanced set of notes, in >> the spirit of the CCLI grant proposal that was posted here a few days >> ago (please go read it and make comments! [1] :). I see these notes as >> incorporating Sage code in examples, like you see in William's number >> theory book or other tutorials that we've seen in various places. >> >> I've spent a while reading up on licenses, and it seems that there are >> three good possibilities for an "open" license that would allow others >> to make modifications and freely redistribute the result: >> >> 1. GNU Free Documentation License 1.3 >> 2. Creative Commons, Attribution-ShareAlike 3.0 >> 3. plain old GPL >> >> GFDL and CC-by-sa are not compatible with GPL, so if I wanted the notes >> to be distributed with Sage (so the examples turn into doctests, etc.), >> if I went with (1) or (2), I'd have to dual-license the notes with GPL. > > > Can you explain why this is the case? If I wrote notes which retained all > copyrights *except* distribution, and allowed unlimited free > distribution, why would that > *prevent* them from being distributed with a GPL program? By notes I mean > text without code which is statically linked to Sage code. >
You're right. I was wrong, basing my opinion on a message from a Creative Commons email message, but further reading of the entire thread showed that it was the *relicensing* of work between CC-by-sa and GPL that wasn't okay, but inclusion of CC-by-sa work (or GFDL, if I understand things correctly) in a GPL package is okay. I guess the situation changes if some example code from the document is actually incorporated into Sage. For example, if in the book, I have a sample function that draws a volumetric data visualization in the document, or if there was a simple calculus function that wasn't already in Sage, then there would be problems if we tried to put those into Sage itself, unless I explicitly dual-licensed the code. Is that correct? Thanks, Jason -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
