Displaying 20 results from an estimated 2000 matches similar to: "Geometrical Interpretation of Eigen value and Eigen vector"
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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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,
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$vectors)
note that I try to get the upper triangular form with eigenvalues on
the diagonal and (possibly) 1 just
2006 Mar 28
2
R crashes during 'eigen'
Hi all,
Hi,
When I want to compute the eigenvalues & eigenvectors of a specific
matrix, R crashes (i.e. it stops responding to any input). I've tried it
with different versions of R (2.1.1, 2.2.0, 2.2.1) - all with crashing
as result.
What I did before the crash was:
M <- as.matrix(read.table("thematrix",header=T))
eigen(M)
If, instead of eigen(M), I use eigen(M,
2005 May 02
14
eigenvalues of a circulant matrix
Hi,
It is my understanding that the eigenvectors of a circulant matrix are given as
follows:
1,omega,omega^2,....,omega^{p-1}
where the matrix has dimension given by p x p and omega is one of p complex
roots of unity. (See Bellman for an excellent discussion on this).
The matrix created by the attached row and obtained using the following
commands
indicates no imaginary parts for the
2008 Mar 03
1
Extracting data from Eigen function
Hi
I need to extract the data returned by Eigen to plot the eigenvectors.
However, when I try and eigv = eigen(covariance); it returns an object with
the matrices containing eigenvalues and vectors.. how can I extract the
eigenvector matrix from this??
When I try mat = eig["vectors"] it returns a matrix with the "$vectors"
string on top , how can I remove this?
code:
> eig
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):
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,
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
2005 Jul 04
1
eigen of a real pd symmetric matrix gives NaNs in $vector (PR#7987)
Full_Name: cajo ter Braak
Version: 2.1.1
OS: Windows
Submission from: (NULL) (137.224.10.105)
# I would like to attach the matrix C in the Rdata file; it is 50x50 and comes
from a geostatistical problem (spherical covariogram)
> rm(list=ls(all=TRUE))
> load(file= "test.eigen.Rdata")
> ls()
[1] "C" "eW"
>
> sym.check = max(abs(C - t(C))) # should
2006 Mar 03
1
NA in eigen()
Hi,
I am using eigen to get an eigen decomposition of a square, symmetric
matrix. For some reason, I am getting a column in my eigen vectors (the
52nd column out of 601) that is a column of all NAs. I am using the option,
symmetric=T for eigen. I just discovered that I do not get this behavior
when I use the option EISPACK=T. With EISPACK=T, the 52nd eigenvector is
(up to rounding error) a
2012 Apr 27
2
find the eigenvector corresponding to the largest eigenvalue
Hi,
If I use the eigen() function to find the eigenvalues of a matrix, how can I find the eigenvector corresponding to the largest eigen value?
Thanks!
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2010 Jun 25
2
Forcing scalar multiplication.
I am trying to check the results from an Eigen decomposition and I need to force a scalar multiplication. The fundamental equation is: Ax = lx. Where 'l' is the eigen value and x is the eigen vector corresponding to the eigenvalue. 'R' returns the eigenvalues as a vector (e <- eigen(A); e$values). So in order to 'check' the result I would multiply the eigenvalues
2012 Apr 19
3
Solve an ordinary or generalized eigenvalue problem in R?
Folks:
I'm trying to port some code from python over to R, and I'm running into a
wall finding R code that can solve a generalized eigenvalue problem
following this function model:
http://docs.scipy.org/doc/scipy/reference/generated/scipy.linalg.eig.html
Any ideas? I don't want to call python from within R for various reasons,
I'd prefer a "native" R solution if one
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]
2008 Jul 18
1
function "eigen" AND Minitab
Hi all. I got a question about eigenvector. I've tried input a symmetric
matrix to both R (using eigen function) and minitab, but the result is
really different. Can anyone tell me what's wrong with that?
Thanks.
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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
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
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
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