similar to: simple question

Displaying 20 results from an estimated 1000 matches similar to: "simple question"

2010 Feb 12
5
logical operations with lists
Sorry, maybe it's easy but I haven't found anything useful: how can I obtain a list C that contains all the members in the list B that are not in list A? This are lists of nanes, not numbers! Thank you Gabriele Zoppoli, MD Ph.D. Fellow, Experimental and Clinical Oncology and Hematology, University of Genova, Genova, Italy Guest Researcher, LMP, NCI, NIH, Bethesda MD Work: 301-451-8575
2010 May 28
3
how to create automatically names for vectors in a loop?
Hi, I want to generate a number of vectors and store them with different names, like this: x=1 while (x<100) { vector#x# = rnorm(100) x=x+1 } where each vector has, at its hand, instead of #x# a number which goes from 1 to 99. How can I do this? Thanks Gabriele Zoppoli, MD Ph.D. Fellow, Experimental and Clinical Oncology and Hematology, University of Genova, Genova, Italy Guest
2010 Sep 03
6
how can I plot bar plots with all the bars (negative and positive) in the same direction????
Dear r-help mailing list, this seems stupid, but I actually don't find the solution: if I have a vector of numbers x of length n, ranging, say, from -3 to 4, if I do barplot (x) all the values below 0 go downwards, and all the positive values go upward. How can I make them all begin from the minimum pointing upwards? Thanks! Gabriele Zoppoli, MD Ph.D. Fellow, Experimental and Clinical
2010 Jan 29
2
question about transpose
Hi all, if I transpose a matrix with t(data), the newly created colums do not appear to have the first row as header. How can I do to have all the newly created columns have their first row as a header? Thanks Gabriele Zoppoli, MD Ph.D. Fellow, Experimental and Clinical Oncology and Hematology, University of Genova, Genova, Italy Guest Researcher, LMP, NCI, NIH, Bethesda MD Work: 301-451-8575
2010 Feb 13
3
how to do calculations in data matrices?
Please give me just a reference where I can find something useful. In summary, I need to : - find the median of each row of a matrix - create a new matrix with each value in the first matrix divided by the median of its row - if a value "a" in the second matrix is < 1, I need to substitute it with 1/a I know that for some of you it must be overeasy, but I swear I googled for two
2010 May 23
3
"order" issue
Hi everybody, this is a real dummy thing. I sorted a matrix based on a given column, and what I get is right, until it comes to columns of negative and positive values; than, "order" orders everything from max to min in the negative values, and then AGAIN from max to min in the positive values!!! Why isn't everything order from max to min, and that's it? Thank you!!! Attached
2010 Jan 29
1
how to create a histogram from a matrix?
Hi, I'm trying to create a frequency histogram for all the values in a table, but when I try to do so, an error is returned, saying that I cannot create a histogram with an obkect of that class. Here's what I do: >library(lattice) >table<-read.table("C:/.../table",header=TRUE,sep="\t") >histogram(table) Please help me!!! Thanks Gabriele Zoppoli, MD
2010 Jan 31
1
permutation analysis with randomly chosen subsets of a matrix
Hello, here is the problem: I want to demonstrate that, on average, the Pearson's correlations of a specified subset of genes from a huge list (>18,000 columns) are higher than any randomly chosen subset of that list. I would therefore like to do a number of tests between that specified subset and randomly chosen ones from the "mother" list. How could I do that? What would be
2010 May 08
1
memory limit
Hi, when I try to import a microarray CEL batch, I get this error message: > myAB <- ReadAffy () Error in .Call("read_abatch", filenames, rm.mask, rm.outliers, rm.extra, : cannot allocate vector of length 1287151200 which, assuming the value is in bites, is below my RAM values (3 Gb recognized by Windows). The isse is, when I try to do memory.limit (size = 3000 ) the
2010 Feb 27
1
help with Gantt chart
Hi, I don't know to solve this error that is returned, even though I understand it: library(plotrix) Ymd.format<-"%Y/%m/%d" gantt.info<-list(labels= c("First task","Second task (1st part)","Third task (1st part)","Second task (2nd part)","Third task (2nd part)", "Fourt task","Fifth task","Sixth
2010 Jan 29
1
help on drawing right colors within a grouped xyplot (Lattice)
Hi, I've lost my mind on it... I have to scatterplot two vectors, grouped by a third variable, with two different dimensions according to whether each cell line in the plot is sensitive or resistant to a given drug, and with a different color for each of 9 tissues of origin. Here's what I've done:
2010 Apr 22
1
cell-based high-throughput chemical compound screens package?
Hi I'm looking for a package to perform quality control, normalization and analysis of high throughput cell-base chemical screens. I know that the cellHTS2 package provides this for siRNA screens. Does anybody know if something like what I'm looking for exists? Thank you! Gabriele Zoppoli, MD Ph.D. Fellow, Experimental and Clinical Oncology and Hematology, University of Genova,
2010 Jan 31
2
help on Venn's diagram
Hello! I have this problem: I want to create a Venn's diagram with three lists of genes'names. The first is all the genome, the second a subset of it comprising all mitochondrial genes, and the third including all genes that correlate with a given gene. This is what I do: > library(gplots) > A<-read.delim("F:/.../mito genes just names.txt") >
2010 Apr 07
0
exporting rotating plot into Powepoint
Hi, I need to export a rotating plot like the one generated from the following function into a PPT slide or something that can be viewed by reviewers of a journal: library(np) library(datasets) data(faithful) f <- npudens(~eruptions+waiting,data=faithful) plot(f,view="rotate",neval=100,phi=30,main="",xtrim=-0.2) Thanks! Gabriele Zoppoli, MD Ph.D. Fellow,
2011 Mar 30
2
calculating the mode in R...
Dear R users I?m aware that the package ?modest? is useful to find the mode in an array. However, I?d like to know if someone has translated the ?mode? function built-in in MATLAB into R language. This function finds the most frequent value in an array (http://www.mathworks.com/help/techdoc/ref/mode.html). Best Fer
2004 May 27
1
automating aov function
I am running the aov function to determine the linear relationship between individual genes and a number of covariates in a micro-array data set. My aov function is working, but I have not been able to write a code to save these results in a matrix. I am using the following code or a slight variation of this code: for(i in 1(length(m[1,])-20) {tmp<- aov(m[,i]~treat, data=m)
2002 Jun 05
1
How to put values of 25 and 75 percentile on boxplot?
Hi all, One quick question: How to put values of 25 and 75 percentile on boxplot? Thanks in advance. Nianqing Xiao, Ph.D NCI Center for Bioinformatics, NIH SAIC/Advanced Systems Group > 6116 EXECUTIVE BLVD 4026J > MSC 8335 > BETHESDA MD 20852 Phone: 301-451-6357 Fax: 301-480-4222 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list --
2004 Mar 08
2
memory problem
I am trying to upload into R 143 Affymetrix chips onto using R on the NIH Nimbus server. I can load 10 chips without a problem, however, when I try to load 143 I receive a error message: cannot create a vector of 523263 KB. I have expanded the memory of R as follows: R --min-vsize=10M --max-vsize=2500M --min-nsize=10M -max-nsize=50M (as specified in help in R). After running this command the
2007 Aug 24
2
Variable Importance - Random Forest
Hello, I am trying to explore the use of random forests for classification and am certain about the interpretation of the importance measurements. When having the option "importance = T" in the randomForest call, the resulting 'importance' element matrix has four columns with the following headings: 0 - mean raw importance score of variable x for class 0 (where
2002 Apr 26
2
Spearman Correlation
Hi all, Is there a convenient way to calculate Spearman correlation coefficients in R? Nick Nianqing Xiao, Ph.D NCI Center for Bioinformatics, NIH SAIC/Advanced Systems Group > 6116 EXECUTIVE BLVD 4026J > MSC 8335 > BETHESDA MD 20852 Phone: 301-451-6357 Fax: 301-480-4222 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read