Displaying 20 results from an estimated 4000 matches similar to: "QR decomposition and rank of a matrix"
2004 Jul 01
1
QR decomposition question
Hi all,
I wonder if this kind of questions are ok in this
list...
Quick question:
What does it mean than the rank of the QR
decomposition of a NxN matrix is N-1 ?
m: NxN matrix
qr(m)$rank equal to (N-1)
Long version:
I'm doing a manova on a matrix of 10 variables
and 16 observations.
> dim(tmp)
[1] 16 10
> fit <- manova( tmp ~ treatment*mouse )
>results <-
2003 Feb 06
6
Confused by SVD and Eigenvector Decomposition in PCA
Hey, All
In principal component analysis (PCA), we want to know how many percentage
the first principal component explain the total variances among the data.
Assume the data matrix X is zero-meaned, and
I used the following procedures:
C = covriance(X) %% calculate the covariance matrix;
[EVector,EValues]=eig(C) %%
L = diag(EValues) %%L is a column vector with eigenvalues as the elements
percent
2004 Apr 30
1
calculation of U and V matrix of SVD decomposition (according to LINPACK, X = UDV')
Hello,
Like QR decomposition, I am looking for decomposition to get U and V matrix
of SVD decomposition (according to LINPACK, X = UDV'). Do you know if there
is a function which could calculate this decomposition?
Look forward to your reply,
Haleh
2006 Sep 01
1
Help with singular value decomposition
Hi wizards, I have seen the function svd of R for singular value
decomposition, but I need to computes the ``economy size'' or ``thin''
singular value decomposition of a matrix in R. Somebody knows how to
do that?. Thanks in advance.
--
Web Page
http://geocities.com/lord_tyranus_96/
2002 Oct 31
1
Re: gregmisc version 0.7.3 now available
Dear Greg,
Thanks for the new release. The decomposition of the SSQ is just what I need!
Regards,
Martin.
Martin Hoyle,
School of Life and Environmental Sciences,
University of Nottingham,
University Park,
Nottingham,
NG7 2RD,
UK
Webpage: http://myprofile.cos.com/martinhoyle
>>> gregory_r_warnes at groton.pfizer.com 10/30/02 07:16PM >>>
Version 0.7.3 of the gregmisc package
2003 Nov 22
3
summary.manova and rank deficiency
Hi all,
I have received the following error from summary.manova:
Error in summary.manova(manova.test, test = "Pillai") :
residuals have rank 36 < 64
The data is simulated data for 64 variables. The design is a 2*2 factorial with 10 replicates per treatment. Looking at the code for summary.manova, the error involves a problem with qr(). Does anyone have a suggestion as to how to
2003 Jul 03
2
SVD and spectral decompositions of a hermitian matrix
Hi:
I create a hermitian matrix and then perform its singular value
decomposition. But when I put it back, I don't get the original
hermitian matrix. I am having the same problem with spectral value
decomposition as well.
I am using R 1.7.0 on Windows. Here is my code:
X <- matrix(rnorm(16)+1i*rnorm(16),4)
X <- X + t(X)
X[upper.tri(X)] <- Conj(X[upper.tri(X)])
Y <-
2008 Aug 13
1
summary.manova rank deficiency error + data
Dear R-users;
Previously I posted a question about the problem of rank deficiency in
summary.manova. As somebody suggested, I'm attaching a small part of
the data set.
#***************************************************
"test" <-
structure(.Data = list(structure(.Data = c(rep(1,3),rep(2,18),rep(3,10)),
levels = c("1", "2", "3"),
class =
2013 May 03
1
MANOVA summary.manova(m) :" residuals have rank"
Dear All, I am trying to perform MANOVA. I have table with 504 columns(species) and 36 rows) with two grouping (season and location)
Zx <- Z[c(4:504)]
Zxm <- as.matrix(Z)
m<- manova(Zxm~Season*location, data=Z)
when I do summary.aov, I get respond for each species but summary.manova
summary.manova(m) :" residuals have rank" 24<501.
What can it be the reason for this error
2004 Aug 30
3
Generalized Singular Value Decomposition (GSVD)
Dear R-users,
I couldn't find a function or some help in R-project web about the
Generalized Singular Value Decomposition. In MatLab there is a simple
function for this algebric issue (gsvd). Is there anything like that in R?
And, if not, could you help me to apply this method in R?
Thanks in advance, Giancarlo
+++++
This mail has been sent through the MPI for Demographic Rese...{{dropped}}
2011 Jan 11
0
SVD, UV-Decomposition and NMF
I am reading the Mining of Massive Datasets Book by Rajaraman and
Ullman. It has a good explanation of Recommendation System at Chapter
9.
But what are the relationship between
1) SVD (Singular Decomposition)
2) UV-Decomposition
3) NMF (Non-negative Matrix Factorization)
In particular, it seems 2) and 3) can be very similar. Is it right?
Thanks.
--
View this message in context:
2007 May 01
1
(PR#9623) qr.coef: permutes dimnames; inserts NA; promises
On Thu, 19 Apr 2007, brech at delphioutpost.com wrote:
> Full_Name: Christian Brechbuehler
> Version: 2.4.1 Patched (2007-03-25 r40917)
> OS: Linux 2.6.15-27-adm64-xeon; Ubuntu 6.06.1 LTS
> Submission from: (NULL) (24.61.47.236)
>
>
> Splus and R have different ideas about what qr.coef(qr()) should return,
> which is fine... but I believe that R has a bug in that it is not
2009 Jan 26
0
Spectral analysis with mtm-svd Multi-Taper Method Combined with Singular Value Decomposition
Hi list,
Does anyone know if there is a library in R that does MTM-SVD method for
spectral analysis?
Thanks
-----
Yasir H. Kaheil
Columbia University
--
View this message in context: http://www.nabble.com/Spectral-analysis-with-mtm-svd-Multi-Taper-Method-Combined-with-Singular-Value-Decomposition-tp21671934p21671934.html
Sent from the R help mailing list archive at Nabble.com.
2008 Apr 15
1
SVD of a variance matrix
Hello!
I suppose this is more a matrix theory question than a question on R,
but I will give it a try...
I am using La.svd to compute the singular value decomposition (SVD) of
a variance matrix, i.e., a symmetric nonnegative definite square
matrix. Let S be my variance matrix, and S = U D V' be its SVD. In my
numerical experiments I always got U = V. Is this necessarily the
case? Or I might
2008 May 16
1
Dimensions of svd V matrix
Hi,
I'm trying to do PCA on a n by p wide matrix (n < p), and I'd like to
get more principal components than there are rows. However, svd() only
returns a V matrix of with n columns (instead of p) unless the argument
nv=p is set (prcomp calls svd without setting it). Moreover, the
eigenvalues returned are always min(n, p) instead of p, even if nv is set:
> x <-
2000 Aug 10
1
svd error (PR#631)
--=====================_24736660==_
Content-Type: text/plain; charset="iso-8859-1"; format=flowed
Content-Transfer-Encoding: quoted-printable
SVD-Error on
R 1.1.0
Windows 98
I get the following error applying svd on a positive definite matrix :
> sk2
[,1] [,2] [,3] [,4] [,5]
[1,] 1.0460139783 0.084356992 -2.810553e-04
2011 Sep 13
1
SVD Memory Issue
I am trying to perform Singular Value Decomposition (SVD) on a Term Document
Matrix I created using the 'tm' package. Eventually I want to do a Latent
Semantic Analysis (LSA).
There are 5677 documents with 771 terms (the DTM is 771 x 5677). When I try
to do the SVD, it runs out of memory. I am using a 12GB Dual core Machine
with Windows XP and don't think I can increase the memory
2007 Oct 17
3
Observations on SVD linpack errors, and a workaround
Lately I'm getting this error quite a bit:
Error in La.svd(x, nu, nv) : error code 1 from Lapack routine 'dgesdd'
I'm running R 2.5.0 on a 64 bit Intel machine running Fedora (8 I think).
Maybe the 64 bit platform is more fragile about declaring convergence.
I'm seeing way more of these errors than I ever have before.
From R-Help I see that this issue comes up from time to
2009 Aug 09
1
Inaccuracy in svd() with R ubuntu package
On two laptops running 32-bit kubuntu, I have found that svd(), invoked
within R 2.9.1 as supplied with the current ubuntu package, returns very
incorrect results when presented with complex-valued input. One of the
laptops is a Dell D620, the other a MacBook Pro. I've also verified the
problem on a 32-bit desktop. On these same systems, R compiled from
source provides apparently
2012 Dec 05
1
Understanding svd usage and its necessity in generalized inverse calculation
Dear R-devel:
I could use some advice about matrix calculations and steps that might
make for faster computation of generalized inverses. It appears in
some projects there is a bottleneck at the use of svd in calculation
of generalized inverses.
Here's some Rprof output I need to understand.
> summaryRprof("Amelia.out")
$by.self
self.time self.pct