similar to: na.omit option in prcomp: formula interface only

Displaying 20 results from an estimated 10000 matches similar to: "na.omit option in prcomp: formula interface only"

2013 Jan 23
0
na.omit option in prcomp: formula interface only
Dear r-devel list, dear Ben I came across a post of Ben Bolker from Feb 2012 (see below) on handling NA values in prcomp(). As I faced the same issue and found Ben's suggestions interesting, I was wondering whether this led to further discussions I might have missed? I understand handling NA values is far from trivial, but would it be possible to add a warning in the documentation, and/or
2002 Oct 29
0
patch to mva:prcomp to use La.svd instead of svd (PR#2227)
Per the discussion about the problems with prcomp() when n << p, which boils down to a problem with svd() when n << p, here is a patch to prcomp() which substitutes La.svd() instead of svd(). -Greg (This is really a feature enhancement, but submitted to R-bugs to make sure it doesn't get lost. ) *** R-1.6.0/src/library/mva/R/prcomp.R Mon Aug 13 17:41:50 2001 ---
2009 Nov 25
1
which to trust...princomp() or prcomp() or neither?
According to R help: princomp() uses eigenvalues of covariance data. prcomp() uses the SVD method. yet when I run the (eg., USArrests) data example and compare with my own "hand-written" versions of PCA I get what looks like the opposite. Example: comparing the variances I see: Using prcomp(USArrests) ------------------------------------- Standard deviations: [1] 83.732400 14.212402
1998 Aug 26
0
prcomp & princomp - revised
My previous post about prcomp and princomp was done in some haste as I had long ago indicated to Kurt that I would try to have this ready for the June release, and it appeared that I would miss yet another release. I also need to get it out before it becomes hopelessly buried by other work. Brian Ripley kindly pointed out some errors, and also pointed out that I was suggesting replacing some
2004 Jan 15
2
prcomp scale error (PR#6433)
Full_Name: Ryszard Czerminski Version: 1.8.1 OS: GNU/Linux Submission from: (NULL) (205.181.102.120) prcomp(..., scale = TRUE) does not work correctly: $ uname -a Linux 2.4.20-28.9bigmem #1 SMP Thu Dec 18 13:27:33 EST 2003 i686 i686 i386 GNU/Linux $ gcc --version gcc (GCC) 3.2.2 20030222 (Red Hat Linux 3.2.2-5) > a <- matrix(rnorm(6), nrow = 3) > sum((scale(a %*% svd(cov(a))$u, scale
2006 May 17
2
prcomp: problem with zeros? (PR#8870)
Full_Name: Juha Heljoranta Version: R 2.1.1 (2005-06-20) OS: Gentoo Linux Submission from: (NULL) (88.112.29.250) prcomp has a bug which causes following error Error in svd(x, nu = 0) : infinite or missing values in 'x' on a valid data set (no Infs, no missing values). The error is most likely caused by the zeros in data. My code and temporary workaround: m = matrix(... ...
2016 Mar 22
3
Memory usage in prcomp
Hi All: I am running prcomp on a very large array, roughly [500000, 3650]. The array itself is 16GB. I am running on a Unix machine and am running ?top? at the same time and am quite surprised to see that the application memory usage is 76GB. I have the ?tol? set very high (.8) so that it should only pull out a few components. I am surprised at this memory usage because prcomp uses the SVD
2016 Mar 22
3
Memory usage in prcomp
Hi All: I am running prcomp on a very large array, roughly [500000, 3650]. The array itself is 16GB. I am running on a Unix machine and am running ?top? at the same time and am quite surprised to see that the application memory usage is 76GB. I have the ?tol? set very high (.8) so that it should only pull out a few components. I am surprised at this memory usage because prcomp uses the SVD
2006 Jun 16
2
bug in prcomp (PR#8994)
The following seems to be an bug in prcomp(): > test <- ts( matrix( c(NA, 2:5, NA, 7:10), 5, 2)) > test Time Series: Start = 1 End = 5 Frequency = 1 Series 1 Series 2 1 NA NA 2 2 7 3 3 8 4 4 9 5 5 10 > prcomp(test, scale.=TRUE, na.action=na.omit) Erro en svd(x, nu = 0) : infinite or missing values in 'x'
2004 Mar 04
1
prcomp: error code 1 from Lapack routine dgesdd
Dear all I have a big matrix of standardized values (dimensions 285x5829) and R fails to calculate the principal components using prcomp() with the following error message: pc <- prcomp(my.matrix) Error in La.svd(x, nu, nv, method) : error code 1 from Lapack routine dgesdd Is the matrix too big? I'm using R-1.8.1 under Unix (Solaris8) and Linux(Suse 8.2). I tried to perform a principal
2016 Mar 24
0
summary( prcomp(*, tol = .) ) -- and 'rank.'
Martin, I fully agree. This becomes an issue when you have big matrices. (Note that there are awesome methods for actually only computing a small number of PCs (unlike your code which uses svn which gets all of them); these are available in various CRAN packages). Best, Kasper On Thu, Mar 24, 2016 at 1:09 PM, Martin Maechler <maechler at stat.math.ethz.ch > wrote: > Following from
2012 Jun 20
1
prcomp: where do sdev values come from?
In the manual page for prcomp(), it says that sdev is "the standard deviations of the principal components (i.e., the square roots of the eigenvalues of the covariance/correlation matrix, though the calculation is actually done with the singular values of the data matrix)." ?However, this is not what I'm finding. ?The values appear to be the standard deviations of a reprojection of
2011 Aug 17
1
prcomp
Hello I am trying to run a PCA on the attached file, but I get this error message: pc<-prcomp(data[,-(1:2)],scale=T)$x Error in svd(x, nu = 0) : infinite or missing values in 'x' Thanks in advance /R -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: Romania_PCA_Chlor1.txt URL:
2004 Apr 14
1
prcomp - error code 18
I am attempting to perform a pca on a data frame of dimension 5000x19, but when I execute pcapres<-prcomp(pres,center=TRUE) the following error message is returned: Error in La.svd(x, nu, nv, method) : error code 18 from Lapack routine dgesdd Where am I going wrong? I am running R-1.8.0 on Debian. Regards, Laura
2016 Mar 25
0
summary( prcomp(*, tol = .) ) -- and 'rank.'
As I see it, the display showing the first p << n PCs adding up to 100% of the variance is plainly wrong. I suspect it comes about via a mental short-circuit: If we try to control p using a tolerance, then that amounts to saying that the remaining PCs are effectively zero-variance, but that is (usually) not the intention at all. The common case is that the remainder terms have a roughly
2006 Mar 25
1
Suggest patch for princomp.formula and prcomp.formula
Dear all, perhaps I am using princomp.formula and prcomp.formula in a way that is not documented to work, but then the documentation just says: formula: a formula with no response variable. Thus, to avoid a lot of typing, it would be nice if one could use '.' and '-' in the formula, e.g. > library(DAAG) > res <- prcomp(~ . - case - site - Pop - sex, possum)
2016 Mar 24
3
summary( prcomp(*, tol = .) ) -- and 'rank.'
Following from the R-help thread of March 22 on "Memory usage in prcomp", I've started looking into adding an optional 'rank.' argument to prcomp allowing to more efficiently get only a few PCs instead of the full p PCs, say when p = 1000 and you know you only want 5 PCs. (https://stat.ethz.ch/pipermail/r-help/2016-March/437228.html As it was mentioned, we already
2016 Mar 25
0
summary( prcomp(*, tol = .) ) -- and 'rank.'
> On 25 Mar 2016, at 10:08 , Jari Oksanen <jari.oksanen at oulu.fi> wrote: > >> >> On 25 Mar 2016, at 10:41 am, peter dalgaard <pdalgd at gmail.com> wrote: >> >> As I see it, the display showing the first p << n PCs adding up to 100% of the variance is plainly wrong. >> >> I suspect it comes about via a mental short-circuit: If we
2002 Oct 29
0
PCA with n << p (was R-1.6.0 crashing on RedHat6.3)
[Moderator's Note: This message needed manual interaction by me, since the attachment originally was declared as ``application/octet-stream'' even though it was only plain text. We do not allow octet-stream (aka binary!) attachments on our mailing list -- for virus/spam filtering reasons. -- MM] We have also encountered the problem Douglas
2010 May 15
2
Attempt to customise the "plotpc()" function
Dear R-list, Among the (R-)tools, I've seen on the net, for (bivariate) Principal Component scatter plots (+histograms), "plotpc" [1] is the one I like most. By default it performs PCA on a bivariate dataset based on R's "princomp()" (which is the eigenvector-based algebraic solution to PCA). I would like to modify "plotpc()" in order be able, as an