similar to: how to do calculations in data matrices?

Displaying 20 results from an estimated 1000 matches similar to: "how to do calculations in data matrices?"

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 Apr 22
6
simple question
Hi how can I find, in a vector of characters, which is the most frequent one? 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 Mobile: 301-204-5642 Email: zoppolig at mail.nih.gov
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 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 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 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,
2000 Sep 19
3
coerce mode list?
Dear R/S users; I'm using S+ version 4 Release 3. and I am trying to do a simple calculation like the following : > X1<-X[1:5] > W1<-W[1:5,1:5] > X1 [1] 1.250000 1.292308 1.176471 0.937500 1.538462 > W1 VAR00003 VAR00004 VAR00005 VAR00006 VAR00007 1 0 1 0 1 0 2 1 0 0 0 1 3 0 0 0
2005 Nov 03
4
merging dataframes
Dear List, I often have to merge two or more data frames containing unique row names but with some columns (names) common to the two data frames and some columns not common. This toy example will explain the kind of setup I am talking about: mat1 <- as.data.frame(matrix(rnorm(20), nrow = 5)) mat2 <- as.data.frame(matrix(rnorm(20), nrow = 4)) rownames(mat1) <- paste("site",
2010 Feb 12
3
Code working but too slow, any idea for how to speed it up ?(no loop in it)
Hello my friends, here is a code I wrote with no loops on matrix that is taking too long (2 seconds and I call him 720 times --> 12 minutes): mat1 and mat2 are both matrix with 103 columns and 164 rows. sequence <- matrix(seq(1 : ncol(mat1))) returns <- apply(sequence, 1, function, mat1= mat1, mat2 = mat2, day = 1) function<- function(mat1, mat2, colNb, day){
2001 Sep 27
1
cuts and breaks
Hi I'm using the "image" function to produce a plot and I want to define the breaks using "cut" and the colors using "heat.colors". > image(interp(mat2[,2],mat2[,1],mat2[,3]),breaks=cut(mat2[,3],30),col=heat.colors(29)) Error in image.default(interp(mat2[, 2], mat2[, 1], mat2[, 3]), breaks = cut(mat2[, : must have one more break than colour The
2010 Jan 29
7
Simple question on replace a matrix row
Hello, I have a matrix mat1 of dim [1,8] and mat2 of dim[30,8], I want to replace the first row of mat2 with mat1, this is what I do: mat2[1,]<-mat1 but it transforms mat2 in a list I don't understand, I want it to stay a matrix... ----- Anna Lippel -- View this message in context: http://n4.nabble.com/Simple-question-on-replace-a-matrix-row-tp1427857p1427857.html Sent from the R help
2005 Oct 06
1
Compare two distance matrices
Hi all, I am trying to compare two distance matrices with R. I would like to create a XY plot of these matrices and do some linear regression on it. But, I am a bit new to R, so i have a few questions (I searched in the documentation with no success). The first problem is loading a distance matrix into R. This matrix is the output of a the Phylip program Protdist and lookes like this: 5