[Scipy-tickets] [SciPy] #1118: scipy.lingalg.eig giving flipped values for complex numbers for the eigenvalues

SciPy Trac scipy-tickets@scipy....
Wed Feb 17 14:25:17 CST 2010


#1118: scipy.lingalg.eig giving flipped values for complex numbers for the
eigenvalues
-----------------------------+----------------------------------------------
  Reporter:  abhijitbendale  |       Owner:  somebody
      Type:  defect          |      Status:  closed  
  Priority:  normal          |   Milestone:  0.8.0   
 Component:  Other           |     Version:  0.7.0   
Resolution:  invalid         |    Keywords:          
-----------------------------+----------------------------------------------
Changes (by pv):

  * status:  new => closed
  * resolution:  => invalid


Comment:

 You are conjugating the eigenvalues in Matlab.
 Remember that `d'` in matlab not only transposes but also complex
 conjugates `d`.

 The values reported by Scipy are correct,
 {{{
 >>> a,v = scipy.linalg.eig(rand_mat)
 >>> xx=np.dot(v, np.dot(np.diag(a), np.linalg.inv(v)))
 >>> abs(xx-rand_mat).max()
 8.8920476648880167e-16
 }}}

-- 
Ticket URL: <http://projects.scipy.org/scipy/ticket/1118#comment:1>
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