I've tackled #1 on my original list, the subject of the most
discussion here.  Found a variety of bugs in the process - caching
mistakes and the problem with matrices over QQbar discussed elsewhere.

My approach to eigenspaces and Galois conjugates was to introduce a
"format" keyword with possible values of 'all' and 'galois'.  The
former attempts to locate eigenvalues in the base field, or extend to
QQbar.  When this fails, the exception message mentions the 'galois'
option.  This latter option preserves current behavior.  The change in
current behavior is that the 'all' option would become the default.

So newbies could see QQbar elements that look familiar by default,
pros can chose Galois conjugates when required (and will discover this
possibility in an exception message).

Two relevant comments from having my head in the code:  (1) outside of
the eigen-stuff code, the only place it was necessary to supply the
'galois' option was in the method for eigenspaces of a graph,  (2)
looking at doctests and code for the other eigen-routines, the more I
felt this change would make for more consistency in the output across
routines.

http://trac.sagemath.org/sage_trac/ticket/11595

-- 
To post to this group, send an email to [email protected]
To unsubscribe from this group, send an email to 
[email protected]
For more options, visit this group at http://groups.google.com/group/sage-devel
URL: http://www.sagemath.org

Reply via email to