Displaying 20 results from an estimated 3000 matches similar to: "eigen anomaly"
2005 Jul 04
0
eigen of a real pd symmetric matrix gives NaNs in $vector (PR#7989)
I would presume this is another manifestation of what I reported
(reproduced below) on 2003-12-01.
cajo.terbraak at wur.nl wrote:
>Full_Name: cajo ter Braak
>Version: 2.1.1
>OS: Windows
>Submission from: (NULL) (137.224.10.105)
>
>
># I would like to attach the matrix C in the Rdata file; it is 50x50 and comes
>from a geostatistical problem (spherical covariogram)
>
2005 Jul 04
1
eigen of a real pd symmetric matrix gives NaNs in $vector (PR#7987)
Full_Name: cajo ter Braak
Version: 2.1.1
OS: Windows
Submission from: (NULL) (137.224.10.105)
# I would like to attach the matrix C in the Rdata file; it is 50x50 and comes
from a geostatistical problem (spherical covariogram)
> rm(list=ls(all=TRUE))
> load(file= "test.eigen.Rdata")
> ls()
[1] "C"  "eW"
> 
> sym.check = max(abs(C - t(C)))    # should
2003 Jun 09
1
understanding eigen(): getting non-normalized eigenvectors
Hi, dear R pros
I try to understand eigen(). I have seen, that eigen() gives the
eigenvectors normalized to unit length.
What shall I do to get the eigenvectors not normalized to unit length?
E.g. take the example:
 A
     
           [,1]       [,2]
  V1  0.7714286 -0.2571429
  V2 -0.4224490  0.1408163
Calculating eigen(A) "by hand" gives the eigenvectors (example from
Backhaus,
2006 Jan 18
1
function 'eigen' (PR#8503)
Full_Name: Pierre Legendre
Version: 2.1.1
OS: Mac OSX 10.4.3
Submission from: (NULL) (132.204.120.81)
I am reporting the mis-behaviour of the function 'eigen' in 'base', for the
following input matrix:
A <- matrix(c(2,3,4,-1,3,1,1,-2,0),3,3)
eigen(A)
I obtain the following results, which are incorrect for eigenvalues and
eigenvectors 2 and 3 (incorrect imaginary portions):
2013 Jun 18
1
eigen(symmetric=TRUE) for complex matrices
R-3.0.1 rev 62743, binary downloaded from CRAN just now; macosx 10.8.3
Hello,
eigen(symmetric=TRUE) behaves strangely when given complex matrices.
The following two lines define 'A', a 100x100 (real) symmetric matrix
which theoretical considerations [Bochner's theorem] show to be positive
definite:
jj <- matrix(0,100,100)
A <- exp(-0.1*(row(jj)-col(jj))^2)
A's being
2006 Jan 27
3
draft of Comment on UCLA tech report
You may  recall that there was a discussion of a technical
report from the statistical consulting group at UCLA.
I have a draft of a comment on that report, which you
can get from
http://www.burns-stat.com/pages/Flotsam/uclaRcomment_draft1.pdf
I'm interested in comments: corrections, additions, deletions.
Patrick Burns
patrick at burns-stat.com
+44 (0)20 8525 0696
http://www.burns-stat.com
2005 Apr 25
1
The eigen function
I'm using R version 2.0.1 on a Windows 2000 operating system. Here is some
actual code I executed:
> test
     [,1] [,2]
[1,] 1000  500
[2,]  500  250
> eigen(test, symmetric=T)$values
[1]  1.250000e+03 -3.153033e-15
> eigen(test, symmetric=T)$values[2] >= 0
[1] FALSE
> eigen(test, symmetric=T, only.values=T)$values
[1] 1250    0
> eigen(test, symmetric=T,
2008 Mar 03
1
Extracting data from Eigen function
Hi
I need to extract the data returned by Eigen to plot the eigenvectors.
However, when I try and eigv = eigen(covariance); it returns an object with
the matrices containing eigenvalues and vectors.. how can I extract the
eigenvector matrix from this??
When I try mat = eig["vectors"] it returns a matrix with the "$vectors"
string on top , how can I remove this?
code:
> eig
2005 Mar 14
1
r: eviews and r // eigen analysis
hi all
i have a question that about the eigen analysis found in R and in
eviews.
i used the same data set in the two packages and found different
answers. which is incorrect?
the data is:
aa ( a correlation matrix)
1	0.9801	0.9801	0.9801	0.9801
0.9801	1	0.9801	0.9801	0.9801
0.9801	0.9801	1	0.9801	0.9801
0.9801	0.9801	0.9801	1	0.9801
0.9801	0.9801	0.9801	0.9801	1
now
> svd(aa)
$d
[1] 4.9204
1997 May 01
0
R-alpha: eigen()
eigen() seems to work for symmetric matrices only. This is out of sync
with the help file.
> trpr.37
           0         1         2         3         4
0 1.00000000 0.0000000 0.0000000 0.0000000 0.0000000
1 0.44444444 0.5555556 0.0000000 0.0000000 0.0000000
2 0.02439024 0.2439024 0.7317073 0.0000000 0.0000000
3 0.00000000 0.0000000 0.2307692 0.7692308 0.0000000
4 0.00000000 0.0000000
2006 Mar 28
2
R crashes during 'eigen'
Hi all,
Hi,
When I want to compute the eigenvalues & eigenvectors of a specific
matrix, R crashes (i.e. it stops responding to any input). I've tried it
with different versions of R (2.1.1, 2.2.0, 2.2.1) - all with crashing
as result.
What I did before the crash was:
M <- as.matrix(read.table("thematrix",header=T))
eigen(M)
If, instead of eigen(M), I use eigen(M,
2013 Jan 31
1
Using eigen() for extracting only few major eigenpairs
Hi everyone,
I am using eigen() to extract the 2 major eigenpairs from a large real
square symmetric matrix. The procedure is already rather efficient, but
becomes somehow slow for real time needs with moderately large matrices
(few thousand lines).
The R implementation statically extracts all eigenvalues (and optionally
associated eigenvectors). I heard about optimizations of the eigen
2007 Nov 29
1
?eigen documentation suggestion
from ?eigen
symmetric: if 'TRUE', the matrix is assumed to be symmetric (or
          Hermitian if complex) and only its lower triangle is used. If
          'symmetric' is not specified, the matrix is inspected for
          symmetry.
I think that could mislead a naive reader as it suggests that, with symmetric=TRUE,
the result of eigen() (vectors and values) depends only on
2010 May 21
2
Data reconstruction following PCA using Eigen function
Hi all,
As a molecular biologist by training, I'm fairly new to R (and statistics!),
and was hoping for some advice. First of all, I'd like to apologise if my
question is more methodological rather than relating to a specific R
function. I've done my best to search both in the forum and elsewhere but
can't seem to find an answer which works in practice. 
I am carrying out
2010 Sep 22
3
eigen and svd
Dear R-helpers,
could anybody explain me briefly what is the difference between
eigenvectors returned by 'eigen' and 'svd' functions and how they are
related?
Thanks in advance
Ondrej Mikula
2005 May 01
2
eigen() may fail for some symmetric matrices, affects mvrnorm()
Hi all,
Recently our statistics students noticed that their Gibbs samplers were 
crashing due to some NaNs in some parameters. The NaNs came from 
mvrnorm (Ripley & Venables' MASS package multivariate normal sampling 
function) and with some more investigation it turned out that they were 
generated by function eigen, the eigenvalue computing function. The 
problem did not seem to happen
2004 Jul 27
4
Problems with Lapack's eigen() on 64-bit
I'm only now realizing that we have severe problems with R on our
AMD 'Opteron' and 'Athlon64' clients running Redhat Enterprise
with all 64-bit libraries (AFAICS).
The Lapack problem happens for R-patched and R-devel both on
the Opteron and the Athlon64.
Here are platform details:
o  "gcc -v" and "g77 -v" both end with the line
   gcc version 3.2.3
2006 Aug 10
3
Geometrical Interpretation of Eigen value and Eigen vector
Dear all,
It is not a R related problem rather than statistical/mathematical. However
I am posting this query hoping that anyone can help me on this matter. My
problem is to get the Geometrical Interpretation of Eigen value and Eigen
vector of any square matrix. Can anyone give me a light on it?
Thanks and regards,
Arun
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2010 Mar 19
1
Howto get unnormalized eigenvectors?
Hi,
I try to calculate the angle between two first eigenvectors of different covariance matrices of biological phenotypic traits for different populations. My issue here is, that all possibilities to do so seem to normalize the eigenvectors to length 1. Although the helpfile of eigen() states, that using eigen(, symmetric = FALSE, EISPACK =TRUE) skips normalization this is (I guess) not applicable
2003 Dec 22
1
La.eigen hangs R when NaN is present (PR#6003)
Full_Name: Sundar Dorai-Raj
Version: 1.8.1
OS: Windows 2000 Professional
Submission from: (NULL) (12.64.199.173)
I discovered this problem when trying to use princomp in package:mva when a
column in my matrix was all zeros and I set cor = TRUE (thus division by 0).
Doing so hangs R, never to return. I have to shut down Rterm in the Task Manager
and lose all work from the current image. I tracked