Opened 8 years ago

Closed 11 months ago

#13932 closed defect (duplicate)

solve_right fails with floating-point matrices

Reported by: vbraun Owned by: jason, was
Priority: major Milestone: sage-duplicate/invalid/wontfix
Component: linear algebra Keywords:
Cc: rbeezer, mjo Merged in:
Authors: Reviewers: Michael Orlitzky
Report Upstream: N/A Work issues:
Branch: Commit:
Dependencies: Stopgaps:

Status badges

Description (last modified by vbraun)

As reported on https://groups.google.com/d/topic/sage-support/TjXY-Nl3PZI/discussion

sage: RF= RealField(52)
sage: Y=matrix(RF,2,2,1)
sage: A = matrix(RF,[[0.24,1,0],[1,0,0]])
sage: A.solve_right(Y)
    ValueError: matrix equation has no solutions

Though it decidedly does have solutions. solve_right() needs to implement a fuzzy check (or default to check=False) if the base field is not exact:

sage: sol = A.solve_right(Y, check=False)
sage: A*sol
[     1.00000000000000 -5.55111512312578e-17]
[    0.000000000000000      1.00000000000000]

Change History (8)

comment:1 Changed 8 years ago by vbraun

  • Description modified (diff)

comment:2 Changed 8 years ago by jdemeyer

  • Milestone changed from sage-5.11 to sage-5.12

comment:3 Changed 7 years ago by vbraun_spam

  • Milestone changed from sage-6.1 to sage-6.2

comment:4 Changed 7 years ago by vbraun_spam

  • Milestone changed from sage-6.2 to sage-6.3

comment:5 Changed 7 years ago by vbraun_spam

  • Milestone changed from sage-6.3 to sage-6.4

comment:6 Changed 12 months ago by gh-mwageringel

  • Cc mjo added
  • Milestone changed from sage-6.4 to sage-duplicate/invalid/wontfix
  • Status changed from new to needs_review

Since #12406, the check is ignored for inexact rings, so this problem does not exist anymore. A doctest for this example has also been added in that ticket, so this ticket can be closed.

comment:7 Changed 12 months ago by mjo

  • Reviewers set to Michael Orlitzky
  • Status changed from needs_review to positive_review

comment:8 Changed 11 months ago by chapoton

  • Resolution set to duplicate
  • Status changed from positive_review to closed
Note: See TracTickets for help on using tickets.