Opened 5 years ago

Last modified 5 years ago

#16243 new enhancement

enable using GAP to compute galois_group

Reported by: dimpase Owned by:
Priority: major Milestone: sage-6.4
Component: number fields Keywords:
Cc: vdelecroix Merged in:
Authors: Reviewers:
Report Upstream: N/A Work issues:
Branch: u/dimpase/enable_using_gap_to_compute_galois_group (Commits) Commit:
Dependencies: Stopgaps:

Description (last modified by dimpase)

GAP can compute Galois groups of number fields of degree up to 15. This will allow avoiding Kash (not available for all platforms, binary only, etc) usage for degrees between 11 and 15. It will need GAP's transitive groups library from the optional spkg database_gap.

Change History (6)

comment:1 Changed 5 years ago by dimpase

  • Component changed from PLEASE CHANGE to number fields
  • Description modified (diff)
  • Type changed from PLEASE CHANGE to enhancement

comment:2 Changed 5 years ago by vdelecroix

  • Cc vdelecroix added

ccing me

comment:3 Changed 5 years ago by dimpase

there is an old bug (cf #6312) on the line 4377 of sage/rings/number_field/number_field.py

$ git annotate -L 4377,4377 src/sage/rings/number_field/number_field.py
f46355fc        (  mabshoff     2008-11-22 19:03:57 -0800       4377)            sage: NumberField(x^3 + 2*x + 1, 'a').galois_group(pari_group=False)    # optional - database_gap

and here is the error:

$ sage -bt --optional=sage,database_gap src/sage/rings/number_field/number_field.py
...
sage -t src/sage/rings/number_field/number_field.py
**********************************************************************
File "src/sage/rings/number_field/number_field.py", line 4377, in sage.rings.number_field.number_field.NumberField_generic.galois_group
Failed example:
    NumberField(x^3 + 2*x + 1, 'a').galois_group(pari_group=False)    # optional - database_gap
Exception raised:
    Traceback (most recent call last):
      File "/usr/local/src/sage/sage/local/lib/python2.7/site-packages/sage/doctest/forker.py", line 480, in _run
        self.execute(example, compiled, test.globs)
      File "/usr/local/src/sage/sage/local/lib/python2.7/site-packages/sage/doctest/forker.py", line 839, in execute
        exec compiled in globs
      File "<doctest sage.rings.number_field.number_field.NumberField_generic.galois_group[13]>", line 1, in <module>
        NumberField(x**Integer(3) + Integer(2)*x + Integer(1), 'a').galois_group(pari_group=False)    # optional - database_gap
      File "cachefunc.pyx", line 1591, in sage.misc.cachefunc.CachedMethodCaller.__call__ (sage/misc/cachefunc.c:9194)
      File "cachefunc.pyx", line 2191, in sage.misc.cachefunc.CachedMethod._instance_call (sage/misc/cachefunc.c:11887)
    TypeError: galois_group() got an unexpected keyword argument 'pari_group'
**********************************************************************
1 item had failures:
   1 of  20 in sage.rings.number_field.number_field.NumberField_generic.galois_group
    [1666 tests, 1 failure, 36.82 s]
----------------------------------------------------------------------
sage -t src/sage/rings/number_field/number_field.py  # 1 doctest failed
----------------------------------------------------------------------
Last edited 5 years ago by dimpase (previous) (diff)

comment:4 Changed 5 years ago by dimpase

  • Branch set to u/dimpase/enable_using_gap_to_compute_galois_group

comment:5 Changed 5 years ago by vbraun_spam

  • Milestone changed from sage-6.2 to sage-6.3

comment:6 Changed 5 years ago by vbraun_spam

  • Milestone changed from sage-6.3 to sage-6.4
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