Hi Marc,

On 2017-07-27, Marc Masdeu <[email protected]> wrote:
> @Simon maybe it would help the OP if you elaborated on why the group 
> cohomology code was not included in the standard Sage...

1. It depends on an optional package with GPL-compatible licence
   at build time and on an optional package with GPL-incompatible
   licence at runtime. It thus can't be standard.
2. When I started the project (quite some time ago), Cython didn't provide
   optional extension modules.
3. Now we do have optional extension modules in the Sage src/ tree.
   I think it is a reasonable policy to reserve these for functionality
   that is provided by standard Sage that can optionally be based
   on a different backend. However, that is not the case for group
   cohomology.

> @Nikhil I would suggest that you concentrate in writing useful code in 
> ergodic theory. How to distribute it is secondary, IMO. For ease of 
> development, you definitely don't want to keep recompiling Sage every time 
> you make a small change in it, so I'd recommend you develop it outside of 
> the Sage source tree.

I don't agree on that recommendation. If you do a small change in your
code, then you need to recompile your code. But that's all. If you do a
small change in the Sage src/ tree, then recompilation of Sage will be
very quick (unless you touch src/structure/element.pxd). And if you use
ccache, the situation will be even easier.

So, in that aspect, there is no difference between src/sage and not
src/sage...

> Once you have code that you are happy to share, put 
> it on github.com or somewhere else for people to look at. You can then 
> worry about how to distribute it then.

If it is clear that the functionality you are adding fits within the
standard scope of Sage, does not depend on packages with GPL-incompatible
licence, and does depend on Sage infrastructure, I'd recommend doing it in
src/sage and open a trac ticket.

Best regards,
Simon

-- 
You received this message because you are subscribed to the Google Groups 
"sage-devel" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/sage-devel.
For more options, visit https://groups.google.com/d/optout.

Reply via email to