Opened 8 years ago

Last modified 6 years ago

#13810 closed defect

Galois group when polynomial has too high degree — at Version 2

Reported by: jmantysalo Owned by: davidloeffler
Priority: minor Milestone: sage-6.8
Component: number fields Keywords:
Cc: Merged in:
Authors: Reviewers:
Report Upstream: N/A Work issues:
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Description (last modified by chapoton)

Older version of Sage was able to say when it couldn't compute Galois group. However, in 5.4, 

NumberField(x^21-2, 'a').galois_group(type="pari").order()

gives answer 252, but with 

NumberField(x^22-2, 'a').galois_group(type="pari").order()

I got 

Error, the variable '_s_' must have a value

I guess this relates to kash interface.

Change History (2)

comment:1 Changed 8 years ago by jmantysalo

Tested with 5.10: After trying R.<x>=QQ[]; (x23-2).galois_group().order() I can't calculate for example R.<x>=QQ[]; (x20-2).galois_group().order(). It seems that internal(?) kash instance fails and Sage don't notice it. User must restart worksheet to get this running again.

comment:2 Changed 8 years ago by chapoton

  • Description modified (diff)
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