normaliz backend isn't ready for generators

[gh-kliem]

sage: P = polytopes.simplex(backend='normaliz')
sage: K.<sqrt2> = QuadraticField(2)
sage: P.dilation(sqrt2)
Traceback (most recent call last):
...
AttributeError: 'generator' object has no attribute 'list'

The reason for this is simple. With optimization in #29200, it seems that generators are passed down to the normaliz backend and this isn't ready for this yet (when converting the data to the normaliz field).

[gh-kliem]

I just marked this as critical, because this is regression.

[gh-kliem]

New commits:

​cb13ddb

allow generators for Vrep/Hrep for backend normaliz

[chapoton]

missing the # optional tag

[chapoton]

and you could use

isinstance(thing, (A, B, C))

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​002e543

added optional tag; small improvement

[gh-kliem]

Replying to chapoton:

and you could use

isinstance(thing, (A, B, C))

Much better. Thanks.

[mkoeppe]

Probably Polyhedron_base should get some _test_... methods to make sure that methods are tested with all backends instead of relying on coverage by copy-paste doctests.

[gh-kliem]

That would probably a good thing to do. I'm not familiar with TestSuite? at all, but that should probably make things better.

[mkoeppe]

Take a look at sage.numerical.backends.GenericBackend. Some time ago I did a similar thing for the MIP backends there. There's also LoggingBackend, which provides a semiautomatic way to make _test... methods from existing doctests.

[gh-kliem]

Thank you for the reference. I will do this, but better in a separate ticket.

[gh-kliem]

I opened #29842 for this.

[gh-kliem]

Thank you.

[fbissey]

In

+            sage: P = polytopes.simplex(backend='normaliz')  # optional - pynormaliz
+            sage: K.<sqrt2> = QuadraticField(2)              # optional - pynormaliz
+            sage: P.dilation(sqrt2)

the last line needs to be optional as well. If you don't have pynormalize you get a nice NameError: name P is not defined message in your doctests.

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​21f9d90

optional tag again

[gh-kliem]

Thanks for catching that.