Opened 8 years ago

Closed 5 years ago

#11432 closed defect (invalid)

LLL function for quadratic forms is wrong

Reported by: mmasdeu Owned by: mmasdeu
Priority: minor Milestone: sage-6.3
Component: quadratic forms Keywords: LLL, quadratic form
Cc: tornaria Merged in:
Authors: Reviewers:
Report Upstream: N/A Work issues:
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Description

The function Q.lll() where Q is a QuadraticForm? is a one-line wrapper around LLL_gram(), which in turn calls Pari.

The description of Q.lll() is that it returns an LLL-reduced quadratic form. However, the function LLL_gram() returns a change of basis matrix, not the resulting quadratic form.

In my opinion this requires a one-line patch, which I can do if someone confirms that this is the problem.

Change History (6)

comment:1 Changed 6 years ago by jdemeyer

  • Milestone changed from sage-5.11 to sage-5.12

comment:2 Changed 6 years ago by vbraun_spam

  • Milestone changed from sage-6.1 to sage-6.2

comment:3 Changed 5 years ago by mmasdeu

I was wrong. When (3 years ago!) I opened the ticket, I failed to realize that one can evaluate a quadratic form on a matrix, and indeed this is what the lll() (rightly) does. I am closing the ticket.

comment:4 Changed 5 years ago by mmasdeu

  • Owner changed from justin to mmasdeu

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

  • Resolution set to invalid
  • Status changed from new to closed
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