Sage 3.2.rc1: automorphism_group() doctest failure on 32 bit in sage/combinat/species/library.py

[sagetrac-mabshoff]

sage -t  devel/sage/sage/combinat/species/library.py 
********************************************************************** 
File "/home/john/sage-3.2.rc1/devel/sage/sage/combinat/species/library.py", 
line 86: 
    sage: a.automorphism_group() 
Expected: 
    Permutation Group with generators [(), ()] 
Got: 
    Permutation Group with generators [()] 
********************************************************************** 

Component: combinatorics

Issue created by migration from https://trac.sagemath.org/ticket/4531

[sagetrac-GeorgSWeber]

comment:1

That seems to be a problem of how Sage displays/prints permutation groups. Internally, everything seems fine. I just produced such a group and I get:

sage: B = species.BinaryTreeSpecies()
sage: a = B.structures([1,2,3,4,5]).random_element(); a
(1*5)*((2*3)*4)
sage: grp = a.automorphism_group()
sage: grp
Permutation Group with generators [(), ()]
sage: grp.list()
[()]

The latter two lines are pretty inconsistent.

[sagetrac-mabshoff]

comment:2

Mike Hansen mentioned in IRC that this is the expected output and will post a patch to fix this in the morning.

Cheers,

Michael

[sagetrac-GeorgSWeber]

comment:3

OK. Thanks for this info!

[williamstein]

comment:4

I am fixing this by changing permutation groups to make their gens be canonicalized by default (meaning they are sorted and duplicates are removed). This is much more in the spirit of Sage. There is still the option to have the generators be exactly what is input (duplicates and all).

[williamstein]

Attachment: sage-4531.patch.gz

[williamstein]

Attachment: doc-4531.patch.gz

[williamstein]

Attachment: sage-4531-part2.patch.gz

trivial followup

[sagetrac-mabshoff]

comment:5

mhansen gave this patch a positive review assuming the doctests pass. Since they do I am changing the subject.

Cheers,

Michael

[sagetrac-mabshoff]

comment:6

Merged all three patches in Sage 3.2.rc2