similar to: How to retrieve data frame column names?

Displaying 20 results from an estimated 10000 matches similar to: "How to retrieve data frame column names?"

2003 Mar 10
1
help--Cox ph model
Dear r-users, I want to use the Cox's ph model to analyze survival data set. How can I extract the model coefs. and Wald test p-value or Score? For example: I use the data set melanom in iSwR package. > library(survival) > data(melanom) > attach(melanom) > cox.model <- coxph(Surv(days,status==1)~sex) > summary(cox.model) Call: coxph(formula = Surv(days, status == 1) ~
2011 Jan 07
2
survval analysis microarray expression data
For any given pre-specified gene or short list of genes, yes the Cox model works fine. Two important caveats: 1. Remeber the rule of thumb for a Cox model of 20 events per variable (not n=20). Many microarray studies will have very marginal sample size. 2. If you are looking at many genes then a completely different strategy is required. There is a large and growing literature; I like Newton
2003 Feb 19
1
How to use Cox PH model to select genes from DNA gene expression profiles?
I'm doing prediction of the survival cases using gene expression profiles(Affymetrix chips). Can somebody tell me how to use the Cox PH model to select genes and make a prediction of survival? Thanks. Guangchun
2007 Oct 22
3
retrieve version information for a package?
Hi, I am looking for a way to find out the version information of installed R packages. ex: >library(affy) >SOME_COMMAND_FOR_VERSION(affy) I know I can do either getRversion() or R.Version() could give me the version of R. I assume there must be a way for me to get version information for the add-on paclages,right? Thanks! Yupu
2003 May 01
2
What' wrong?
I try to do single proportion test on my category data. Here is my R script: library("ctest") catSignifTest <- function( catFile ) { ############################################################### ## Get the data sets from text file catData <- read.table( catFile ) ncols <- length(catData) nrows <- length(catData[,1]) ncol1 <- ncols - 1 probeNbr
2010 Sep 20
1
Please help with this error - new to
I am getting the following error in my script. I am very very new to R and have obtained this script from another person. #read file in (dummy data) starburst.plot<-function(affy.fold, affy.FDR)(ifelse( ((affy.fold) >=0), -1*log10(affy.FDR), 1*log10(affy.FDR))) starburst.plot<-function(meth.fold, meth.FDR)(ifelse( ((meth.fold) >=0), -1*log10(meth.FDR), 1*log10(affy.FDR))) At my next
2007 Aug 29
4
retrieve p-value from a cox.obj
I have a cox.obj named obj, obj <- coxph( Surv(time, status) ~ group, surv.data) now I want to retrieve the p-value from obj, so that I can run this hundreds of times and plot out the distribution of the p-value. could anyone tell me how to get p-value from obj? thanks, -- View this message in context: http://www.nabble.com/retrieve-p-value-from-a-cox.obj-tf4348520.html#a12389652 Sent from
2004 Oct 05
1
How to install affy package in R?
Hello, I am trying to install affy package in R as follow: >R CMD INSTALL -l lib ~/rstuffs/affy_1.4.32.tar.gz Then I get an error at the end: Warning message: There is no package called 'Biobase' in: library(package, character.only = TRUE, logical = TRUE, warn.conflicts = warn.conflicts, [1] "ProgressBarText" [1]
2003 Oct 31
2
Creating packages in 1.8
Hi, I decided to upgrade to 1.8 today... :-) Anyway, we are writing our own package that is dependent on a bioconductor library - 'affy'. I've checked and when I fire up R, library(affy) behaves as expected... so it all seems to be installed and OK... In the DESCRIPTION file in my package source I have the line: Depends: affy When I run R CMD check simpleaffy I get to: ... *
2010 Jun 23
1
mhplot error with test example: "ylim not found"
Hello all, I am trying to make a genome association plot for p-values related to SNPs and was fortunate to find that R contains a package that produces Manhattan plots which is what's preferred for my current project. The function mhtplot() is found in the 'gap' package which I installed in R 2.11.1 on Windows. I thought I'd test out the function first with the examples they
2007 Mar 23
1
can't load just saved R object "ReadItem: unknown type 65"
I have run into a problem loading a just saved R object using R-devel. I have been saving and loading this particular type of R object for a long while and never ran into this problem. I save, then immediately reload (to test save) and get "ReadItem: unnknown type 65". This error is reproducible after logout from server and restart of emacs and R. Below is my output and
2007 Mar 23
1
can't load just saved R object "ReadItem: unknown type 65"
I have run into a problem loading a just saved R object using R-devel. I have been saving and loading this particular type of R object for a long while and never ran into this problem. I save, then immediately reload (to test save) and get "ReadItem: unnknown type 65". This error is reproducible after logout from server and restart of emacs and R. Below is my output and
2005 Jul 21
1
principal component analysis in affy
Hi, I have been using the prcomp function to perform PCA on my example microarray data, (stored in metric text files) which looks like this: 1a 1b 1c 1d 1e 1f ...................................................4r 4s 4t g1 1.2705 1.2766 ...........................................................2.0298 g2 0.1631
2009 Nov 27
1
problem tick marker and text
Hi R-ers, I am struggling with my x-axis in a association plot. What I would like is to place the labels of the x-axis between the tick markers and normally the labels are printed at the place where the tick marker is placed. I don???t want to move the tick marker (it gives the switch between one chromosome and the next) but I just want to put the chromosome number in between the
2004 Jul 06
2
ESS does not recognize installed libraries
Hi, all. Something strange happened to my ESS. I use Mac OS X. When R is used in stand alone mode, it recognizes external libraries like "affy", "e1071" etc. However, when R is invoked through ESS in Emacs, it produces errors like: Error in library(affy) : There is no package called 'affy' Interestingly, I remember I successfully used these libraries through ESS in
2007 Oct 04
1
Problem with .libPaths & Rterm.exe (under Vista)
Dear list, I?m using R embedded in another program (coded in tcl/tk) under Windows Vista. In this context I don?t launch Rgui.exe but rather Rtem.exe. Now I have a problem finding libraries not specifically installed as administrator (and which are not in the path ?program files? but in Contacts\Documents of the current user). To be precise, the user launching my tcl/tk program can?t find
2006 Feb 16
2
how to retrieve robust se in coxph
Hi, I am using coxph in simulations and I want to store the "robust se" (or "se2" in frailty models) for each replicate. Is there a function to retrieve it, like vcov() for the variance estimate? Thanks! Lei Liu Assistant Professor Division of Biostatistics and Epidemiology Dept. of Public Health Sciences School of Medicine University of Virginia 3181 Hospital West
2012 Oct 21
1
Changing a for loop to a function using sapply
Apparently there is one or more concepts that I do not fully understand from the descriptions of a function and the apply material. I have been reading the mail from this forum and have learned much but, in this case, what I have been reading here and from the manual isn't enough. The following code produces what I want with the for loop. From what I have read from this forum, a for
2006 Oct 12
1
getMethods() not finding all methods
Running R2.4.0 on Apple Mac OS X 10.4.8, in Emacs ESS mode, and also R.app. In an attempt to learn a bit more about a particular method (geneNames in package affy) I invoked getMethods("geneNames") which produced geneNames methods, but not the one in affy (output below). I had to know the signature (AffyBatch) in order to find the method > getMethod("geneNames",
2009 Jul 13
1
Problems installing R
Hi, I am new to Linux and have a linux machine running ubuntu (hardy heron). I installed R 2.9.1 using the deb file provided on the R website. However I can't install 'affy' - one of the R packages and apparently this is because of the lib settings. I've tried to install R using the command line but I can't add: deb http://cran.uk.r-project.org/bin/linux/ubuntu hardy to my