#5485: issue with dimension of ideals in polynomial rings
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 Reporter:  AlexGhitza           |       Owner:  malb      
     Type:  defect               |      Status:  new       
 Priority:  major                |   Milestone:  sage-3.4.1
Component:  commutative algebra  |    Keywords:            
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Comment(by john_perry):

 Looking up a little bit about Krull dimension, I think I see the problem:
 ZZ has Krull dimension 1, whereas fields have Krull dimenson 0. The given
 code assumes that the ground ring is a field. This is assumed by the
 source material in Cox, Little, and O'Shea, so the old code almost works
 as it is supposed to.

 There was also an issue with the implementation so that even the zero
 ideal in a field would be wrong. This is now fixed, so the code works "as
 it is supposed to", by which I mean that it works in fields, per the
 source material.

 However, Alex is right that this is not quite the same as what the
 documentation promises, since the documentation talks as if the ring is
 arbitrary. So, it doesn't '''really''' work the way it is supposed to. I
 have an idea for a fix for the case where the ground ring is not a field:
 add the Krull dimension of the ground ring to whatever is computed by the
 current code.

 But is this correct? If so, the fix is trivial. If not, this will require
 a lot more work, since all my references assume fields.

-- 
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/5485#comment:2>
Sage <http://sagemath.org/>
Sage - Open Source Mathematical Software: Building the Car Instead of 
Reinventing the Wheel

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