eigen() error: R Version 1.6.1 on Mac OS X (PR#2550)

Actually, I only get the problem if I use R Version 1.6.2 as automatically
installed by 'fink'.  If I download the source directly myself for Version
1.6.2 from CRAN and compile it, then I get the proper eigenvalues.  Seems
strange to me - I thought that the source code in the fink repository should
be identical to that at CRAN?

-- Dan --

------ Forwarded Message
From: Daniel E. Weeks <dweeks@watson.hgen.pitt.edu>
Date: Wed, 05 Mar 2003 16:09:48 -0500
To: Stefano Iacus <jago@mclink.it>
Cc: <R-devel@stat.math.ethz.ch>
Subject: Re: [Rd] eigen() error: R Version 1.6.1 on Mac OS X (PR#2550)

Dear Stefano,

Yes, I have updated to R Version 1.6.2  (2003-01-10), running it in a
Terminal window under Darwin Kernel Version 6.4.

And, while La.eigen() appears to work fine, I still have the same problem
with eigen():

x

     X1    X2    X3    X4    X5
1 3.240 2.592 2.592 2.592 2.592
2 2.592 3.240 2.592 2.592 2.592
3 2.592 2.592 3.240 2.592 2.592
4 2.592 2.592 2.592 3.240 2.592
5 2.592 2.592 2.592 2.592 3.240

La.eigen(x)$values

[1] 13.608  0.648  0.648  0.648  0.648

eigen(x)$values

[1] 13.123930  0.648000  0.648000  0.648000 -1.732930

I was hoping that updating to Version 1.6.2 would make my bug go away.

But if you can not reproduce this bug, then what is it about my system that
is different from yours?

Thank you,
  -- Dan --

On 2/14/03 4:37 PM, Stefano Iacus at jago@mclink.it wrote:

Under Darwin R 1.6.2 and R-1.6.1 I get

sg

     [,1]  [,2]  [,3]  [,4]  [,5]
[1,] 3.240 2.592 2.592 2.592 2.592
[2,] 2.592 3.240 2.592 2.592 2.592
[3,] 2.592 2.592 3.240 2.592 2.592
[4,] 2.592 2.592 2.592 3.240 2.592
[5,] 2.592 2.592 2.592 2.592 3.240

eigen(sg)$values

[1] 13.608  0.648  0.648  0.648  0.648

as well as under Carbon R 1.6.1 and 1.6.2

I cannot reproduce your behaviour.

stefano




On Venerd?, feb 14, 2003, at 21:37 Europe/Rome,
dweeks@watson.hgen.pitt.edu wrote:

Consider this matrix:

sg

     X1    X2    X3    X4    X5
1 3.240 2.592 2.592 2.592 2.592
2 2.592 3.240 2.592 2.592 2.592
3 2.592 2.592 3.240 2.592 2.592
4 2.592 2.592 2.592 3.240 2.592
5 2.592 2.592 2.592 2.592 3.240

If I compute the eigenvalues of the 'sg' matrix using R Version 1.5.0
(2002-04-29) under Linux (or using Version 1.4.0  (2001-12-19) under
Solaris), I obtain:

eigen(sg)

$values
[1] 13.608  0.648  0.648  0.648  0.648

I also obtain the same eigenvalues under R Version 1.5.1  (2002-06-17)
under
Mac OS X 10.2.3.

However, if I compute the eigenvalues of the 'sg' matrix using R
Version
1.6.1  (2002-11-01) under Mac OS X 10.2.3, I obtain a different answer:

eigen(sg)

$values
[1] 13.123930  0.648000  0.648000  0.648000 -1.732930

det(sg)

[1] 2.399354

det(sg,method="eigenvalues")

[1] -7.312317


Thanks,
 -- Dan --

------ End of Forwarded Message