Displaying 20 results from an estimated 2000 matches similar to: "Separating Columns in Excel Export from R"
2007 Feb 28
2
topTable function from LIMMA
Dear R-Help,
I am using the function "topTable" from the LIMMA package. To estimate
adjusted P-values there are several options (adjust="fdr" , adjust="BH")
as shown below:
topTable(fit, number = 10, adjust = "BH", fit$Name)
I guess any of these options (fdr, BH, etc.) is using a default of
FDR=0.05 which is quite conservative (i.e., very
2004 Dec 20
2
problems with limma
I try to send this message To Gordon Smyth at smyth at vehi,edu.au but it bounced
back, so here it is to r-help
I am trying to use limma, just downloaded it from CRAN. I use R 2.0.1 on Win XP
see the following:
> library(RODBC)
> chan1 <- odbcConnectExcel("D:/Data/mgc/Chips/Chips4.xls")
> dd <- sqlFetch(chan1,"Raw") # all data 12000
> #
> nzw <-
2008 Feb 11
3
Difference between P.Value and adj.P.Value
Hallo,
> fit12<-lmFit(qrg[,1:2])
> t12<-toptable(fit12,adjust="fdr",number=25,genelist=qrg$genes[,1])
> t12
ID logFC t P.Value adj.P.Val B
522 PLAU_OP -6.836144 -8.420414 5.589416e-05 0.01212520 2.054965
1555 CD44_WIZ -6.569622 -8.227938 6.510169e-05 0.01212520 1.944046
Can anyone tell me what the difference is between P.Value
2005 Jan 08
1
p.adjust(<NA>s), was "Re: [BioC] limma and p-values"
>>>>> "GS" == Gordon K Smyth <smyth@wehi.edu.au>
>>>>> on Sat, 8 Jan 2005 01:11:30 +1100 (EST) writes:
<.............>
GS> p.adjust() unfortunately gives incorrect results when
GS> 'p' includes NAs. The results from topTable are
GS> correct. topTable() takes care to remove NAs before
GS> passing
2012 Mar 30
1
Help with the lumi R package
Hi all,
My name is Amy, I am a masters student in Bioinformatics at North Carolina
State University. I am working on a project and I am trying to use the lumi
R package for microarray data analysis. I have shown the sample code here
and have questions about modifying the sample code for my own data.
lumi package in R, example.lumi, the sample data has 8000 features and 4
samples
I have
2004 Feb 20
1
Stupid Limma question..
Hi all. I've got a really dumb question for anyone. How do I write the
output of a limma analysis (basically the topTable) to a text file? I want
to output the topTable for the entire microarray (not really a topTable
anymore I suppose..). Thanks for any advice!
-Josh
2008 Jan 24
3
store variable as tab-del. txt-file
Hallo,
how can I store a variable as a tab-delimited txt-file? I crated a
variable with the following commands:
> fit12<-lmFit(qrg[,1:2])
> t12<-toptable(fit12,adjust="fdr",number=25,genelist=qrg$genes[,1])
> t12
ID logFC t P.Value adj.P.Val B
522 PLAU_OP -6.836144 -8.420414 5.589416e-05 0.01212520 2.054965
1555 CD44_WIZ -6.569622
2011 Nov 22
2
filtering probesets with Bioconductor?
Hi,
I am relatively new to R and Bioconductor and am trying to filter the
topTable that I generated of differentially expressed genes from my
normlized eset file comprised of ~ 40 HG-133A Affy microarrays . I would
like to see if particular probesets are represented in this list.
Alternatively I would like to
generate a topTable of differentially expressed genes using only specified
probesets
2006 Dec 17
2
question
Dear R users,
I'am using marray and Limma packages to analyze genepix output.
1) how can I filter bad spots from my data (data contains 3 types of bad
spots).
my experiment contains 12 samples and the bad spot are not associated to the
same probes
2) how can I remove control probes from my data ?
I'm sorry, i'm new with R and I can't find answer in packages doc.
best regards,
2006 Sep 26
2
Vectorise a for loop?
Hi R guru coders
I wrote a bit of code to add a new column onto a "topTable" dataframe.
That is a list of genes processed using the limma package. I used a for
loop but I kept feeling there was a better way using a more vector
oriented approach. I looked at several commands such as "apply", "by"
etc but could not find a good way to do it. I have this feeling there
2004 Dec 21
0
Fwd: problems with limma
On Wed, December 22, 2004 12:11 am, r.ghezzo at staff.mcgill.ca said:
> ----- Forwarded message from r.ghezzo at staff.mcgill.ca -----
> Date: Mon, 20 Dec 2004 15:45:11 -0500
> From: r.ghezzo at staff.mcgill.ca
> Reply-To: r.ghezzo at staff.mcgill.ca
> Subject: [R] problems with limma
> To: r-help at stat.math.ethz.ch
>
> I try to send this message To Gordon
2010 Mar 29
1
stuck with affy / limma
Hi,
I have a question concerning the analysis of some affymetrix chips. I
downloaded some of the data from GEO GSE11324 (see below). In doing so I'm
stuck after I identified the probesets with significant changes. I have
problems in assigning probeset specific gene names as well as getting the
genomic coordinates. Furthermore I have no clue how to deal with the fact,
that most genes have
2006 Jun 28
0
Help with topTable function in limma
Hello,
I have just completed an analysis of microarray data using the limma package. The analysis appears to have worked fine. However, when I use the topTable function to get the significant genes, I get the following error:
> topTable(fit2,coef=5,adjust="fdr")
Error in array(x, c(length(x), 1), if (!is.null(names(x))) list(names(x), :
attempt to set an attribute on NULL
2007 Aug 03
4
FW: Selecting undefined column of a data frame (was [BioC] read.phenoData vs read.AnnotatedDataFrame)
Hi all,
What are current methods people use in R to identify
mis-spelled column names when selecting columns
from a data frame?
Alice Johnson recently tackled this issue
(see [BioC] posting below).
Due to a mis-spelled column name ("FileName"
instead of "Filename") which produced no warning,
Alice spent a fair amount of time tracking down
this bug. With my fumbling fingers
2006 May 25
1
Question regarding reading arrayvision files in limma
Hi Everyone,
I have been trying to read some Arrayvision files( 2 channel cDNA) and
am having some
problem. My code is :
setwd('C:/work/data/limma/ndd1');
files <- c('ndd1_1.txt','ndd1_2.txt','ndd1_3.txt');
RG=read.maimages(files,"arrayvision",sep="\t");
#Normalisation
MA=normalizeWithinArrays(RG);
#plotPrintTipLoess(MA);
#Fit Linear
2012 Mar 30
0
Help with lumi package R code
Hi all,
My name is Amy, I am a masters student in Bioinformatics at North Carolina
State University. I am working on a project and I am trying to use the lumi
R package for microarray data analysis. I have shown the sample code here
and have questions about modifying the sample code for my own data.
lumi package in R, example.lumi, the sample data has 8000 features and 4
samples
I have
2012 May 04
0
LIMMA decideTests result zero from contrast matrix
Dear All,
I am using the LIMMA package to create 2 contrasts for my data and then calculating the vennCounts of the decideTests from the contrast.fit to be able to create venn Diagrams.
The code works fine but the summary(results) shows zeros for all i.e. no gene were up regulated or downregulated. This is not true for my data since toptable output shows Log fold change greater than > 2.
I am
2012 Mar 19
1
hgu133plus2hsentrezgprobe library
Hello R community,
I am processing raw Affymetrix CEL files and I am using the Michigan custom
CDF library hgu133plus2hsentrezgprobe. I have been looking for
documentation on the function that it contains...I am specifically
interested in converting probe names to gene symbols. Does anybody know
where I can find it?
Thank a lot!
Eleni
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2005 May 10
2
Running R from Perl program
Hi all,
Is it possoble to include an R function in a Perl program? I would like to use
the "limma" library for microarray analysis, and have no clue how this
can be done.
Thanks in Advance
-Tarun
2004 Nov 12
0
Design Matrix
Dear all,
I need some help on matrix design and B statistics by using limma package.
I want to compare gene expression in 2 groups of cDNA samples.
The experiment compares 4 treated mice(#1,#2,#3,#4) and 4 control mice
(#5,#6,#7,#8).
The target file is
FileName Cy3 Cy5
mice1.spot Control_#5 Treat_#1
mice2.spot Treat_#1 Control_#5
mice3.spot Control_#6 Treat_#2