Displaying 20 results from an estimated 5000 matches similar to: "The eigen function"
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,
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):
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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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 Oct 18
1
Calculation of Eigen values.
Dear all R users,
Can anyone tell me to calculate Eigen value of any real symmetric matrix
which algorithm R uses? Is it Jacobi method ? If not is it possible to get
explicit algorithm for calculating it?
Thanks and regards,
Arun
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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
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
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
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
2011 Nov 14
2
How to compute eigenvectors and eigenvalues?
Hello.
Consider the following matrix:
mp <- matrix(c(0,1/4,1/4,3/4,0,1/4,1/4,3/4,1/2),3,3,byrow=T)
> mp
[,1] [,2] [,3]
[1,] 0.00 0.25 0.25
[2,] 0.75 0.00 0.25
[3,] 0.25 0.75 0.50
The eigenvectors of the previous matrix are 1, 0.25 and 0.25 and it is not a diagonalizable matrix.
When you try to find the eigenvalues and eigenvectors with R, R responses:
> eigen(mp)
$values
[1]
2006 Mar 03
1
NA in eigen()
Hi,
I am using eigen to get an eigen decomposition of a square, symmetric
matrix. For some reason, I am getting a column in my eigen vectors (the
52nd column out of 601) that is a column of all NAs. I am using the option,
symmetric=T for eigen. I just discovered that I do not get this behavior
when I use the option EISPACK=T. With EISPACK=T, the 52nd eigenvector is
(up to rounding error) a
2008 Jun 18
2
highest eigenvalues of a matrix
DeaR list,
I happily use eigen() to compute the eigenvalues and eigenvectors of
a fairly large matrix (200x200, say), but it seems over-killed as its
rank is limited to typically 2 or 3. I sort of remember being taught
that numerical techniques can find iteratively decreasing eigenvalues
and corresponding orthogonal eigenvectors, which would provide a nice
alternative (once I have the
2010 Sep 22
3
eigen and svd
Dear R-helpers,
could anybody explain me briefly what is the difference between
eigenvectors returned by 'eigen' and 'svd' functions and how they are
related?
Thanks in advance
Ondrej Mikula
2010 Jun 25
2
Forcing scalar multiplication.
I am trying to check the results from an Eigen decomposition and I need to force a scalar multiplication. The fundamental equation is: Ax = lx. Where 'l' is the eigen value and x is the eigen vector corresponding to the eigenvalue. 'R' returns the eigenvalues as a vector (e <- eigen(A); e$values). So in order to 'check' the result I would multiply the eigenvalues
2008 Jun 03
3
matlab eigs function in R
Hello
Does anybody know how one can compute d largest eigenvalues/eigenvectors in
R, like in MATLAB eigs function ? eigen function computes all
eigenvectors/eigenvalues, and they are slightly different than those
generated by matlab eigs.
Thanks in advance
--
View this message in context: http://www.nabble.com/matlab-eigs-function-in-R-tp17619641p17619641.html
Sent from the R help mailing list
1997 May 18
2
R-alpha: Eigenvalue Computation Query
I have been looking at the "eigen" function and have reintroduced the
ability to compute (right) eigenvalues and vectors for non-symmetric
matrices. I've also made "eigen" complex capable.
The code is based on the eispack entry points RS, RG, CH, CG (which is
what S appears to use too). The problem with both the S and R
implementations is that they consume huge amounts
2004 Oct 19
3
matrix of eigenvalues
I thought that the function
eigen(A)
will return a matrix with eigenvectors that are independent of each
other (thus forming a base and the matrix being invertible). This
seems not to be the case in the following example
A=matrix(c(1,2,0,1),nrow=2,byrow=T)
eigen(A) ->ev
solve(ev$vectors)
note that I try to get the upper triangular form with eigenvalues on
the diagonal and (possibly) 1 just
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
2010 Jan 11
3
Eigenvectors and values in R and SAS
Hi,
I was wondering if function eigen() does something different from the
function call eigen() in SAS.
I'm in the process of translating a SAS code into a R code and the values of
the eigenvectors and eigenvalues of a square matrix came out to be different
from the values in SAS.
I would also appreciate it if someone can explain the difference in simple
terms. I'm pretty new to both
2003 Apr 03
2
Matrix eigenvectors in R and MatLab
Dear R-listers
Is there anyone who knows why I get different eigenvectors when I run
MatLab and R? I run both programs in Windows Me. Can I make R to produce
the same vectors as MatLab?
#R Matrix
PA9900<-c(11/24 ,10/53 ,0/1 ,0/1 ,29/43 ,1/24 ,27/53 ,0/1 ,0/1 ,13/43
,14/24 ,178/53 ,146/244 ,17/23 ,15/43 ,2/24 ,4/53 ,0/1 ,2/23 ,2/43 ,4/24
,58/53 ,26/244 ,0/1 ,5/43)
#R-syntax