Displaying 20 results from an estimated 3000 matches similar to: "the r package for svdpack?"
2009 Sep 15
1
How can I use R:sort function in C code?
Hi, I wrote a C extension for R. Within the C code I wanted to invoke the
R's sort function, with the argument "index.return = TRUE". I found it is a
difficult problem, how can I do that? I have implemented the decreasing
sorting by the code "PROTECT(R_fcall = lang3(install("sort"), x, desc));",
but how to define the "index.return" argument?
Thanks in
2004 Mar 26
1
Using R's LAPACK & Related files in Visual C++
I am a relative newcomer to both the R and C/C++
software worlds -- I'm taking a C Programming class
currently. I noticed the other day that the
C:\Program Files\R1_8_1\src\include\R_ext
directory on my WinXP box has the header files
BLAS.h
Lapack.h
Linpack.h
RLapack.h
I am interested in (perhaps) using one or more of
these
header files in a straight C program I'm working on in
Visual
2001 Nov 16
2
DGESDD from Lapack for R-1.4.0?
Hi,
I'm just wondering if it is planned to include the Lapack
routine DGESDD (and friends) in R-1.4.0? This is faster
(supposedly by a factor of ~6 for large matrices) than
DGESVD which is currently (R-1.3.1) called by La.svd.
And if it is not in the plans yet, is there a chance it
could be? I've added it to my local version of R-1.3.1 and
so far see a factor of 4 improvement over
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:
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
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 <-
2004 Jul 01
1
QR decomposition and rank of a matrix
In summary.manova the qr decomposition of a NxN
matrix
is calculated and for some cases is giving me
a rank < N.
However, following suggestions of professor Ripley to
calculate the rank of a Matrix
On 7 Jun 2002, Brian Ripley wrote:
> For a more reliable answer, look at the SVD
> (function svd) and look at the
> singular values. For example (from lda.default)
X.s <-
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
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 <-
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
--
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Sent from the R help mailing list archive at Nabble.com.
2010 Sep 02
0
using R's svd from outside R
Hi,
I have to compute the singular value decomposition of rather large
matrices. My test matrix is 10558 by 4255 and it takes about three
minutes in R to decompose on a 64bit quadruple core linux machine. (R is
running svd in parallel, all four cores are at their maximum load while
doing this.) I tried several blas and lapack libraries as well as the
gnu scientific library in my C++ programm.
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
2008 Feb 23
1
Error in ma.svd(X, 0, 0) : 0 extent dimensions
Hi,
I run a maanova analysis and found this message error:
Error in ma.svd(X, 0, 0) : 0 extent dimensions
I did a google search and found this:
\item ma.svd: function to compute the sigular-value decomposition
of a rectangular matrix by using LAPACK routines DEGSVD AND ZGESVD.
\item fdr: function to calculate the adjusted P values for FDR control.
I did a search for LAPACK and
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
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/
2007 Apr 19
0
qr.coef: permutes dimnames; inserts NA; promises minimum-length (PR#9623)
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
internally consistent, and another separate bug in the documentation.
In particular, on
2007 Jun 04
2
rq matrix decomposition
I specifically need rq matrix decomposition (and not qr).
Looking at netlib site for LAPACK it does provide rq whereas LINPACK not.
Looking at companion qr in R I see how in base it wraps with a .Call but I
do not have success in doing that for a similar .Call for rq.
Anyone done this or can provide matrix rewrites that allow me to do the rq
decomposition with existing R funcs?
Regards MJ
2014 Dec 16
3
BLAS/LAPACK routine 'DLASCL' gave error code -4 in liblapack3 Version 3.5.0
Dear all
Some computations gave a matrix. The single value decomposition of it worked fine previously, after an system upgrade I get the following error:
-----
> La.svd(x,256,256)
Error in La.svd(x, nu, nv) :
BLAS/LAPACK routine 'DLASCL' gave error code -4
-----
Erroneous Matrix: ftp://usys-ftp.ethz.ch/ITES/STEP/nussbaum/R/matrix-lapack-error4.RData /.csv
Operating System: Debian 8
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