similar to: Matrix to "indexed" vector

Hello, Is there a way to extract multiple columns from a dataframe using their names instead of their numbers? Currently I use: data2 <- data1[, c(1,3,9)] And I am looking for something like data2 <- data1[, c("XX","YY","ZZ")] I use the same dataframe for many purposes, and I run codes that change the order of the columns every time. Many thanks, Adrian

Hi all, I need to compute some "occurence matrix": given a zero matrix and a set of paired indexes, I want to store the number of occurences of each paired index in a matrix. The paired indexes are stores as an index matrix. I prefere not to use loops for performances purpose. Here follows a dummy example: > occurence <- matrix(0, 2, 2); data [,1] [,2] [1,] 0 0

Hello everyone,   I have a matrix like :   mat <- matrix(rnorm(12*3), 3)   Now I want to break that matrix in 4 parts each of them are matrix of (3x3) and put those 4 matrices in a "list" object of length 4   Can anyone please tell me how to do that? Get your new Email address! Grab the Email name you&#39;ve always wanted before someone else does! [[alternative HTML

Hi users, I am not sure to understand the help page about do.call. -- do.call(what, args) args: a _list_ of arguments to the function call. The 'names' attribute of 'args' gives the argument names. -- If we take the following sample data: > (tab=as.data.frame(table(factor(1:10)))) Var1 Freq 1 1 1 2 2 1 3 3 1 4 4 1 5 5

Hi R-listers, I am trying to better undertand what we would call "functional paradigm" use of S/R to better map my programming activities in other languages. This little function is aimed to create an object (at the end end, it would have it's own class): -- myObject =function(){ list( a=1, foo=function(b) { cat("b:",b)

Hi, is there any way to keep a sub matrix dimension? exemple : i1<-1; i2<-1 j1<-2; j2<-3; ret <-matrix(1,4,4)[i1:i2,j1:j2] ; dim(ret) is NULL because the submatrix single col or single row is coerce to a vector automaticaly. How can i bypass this cast : submatrix->vector ??????? Thank you. --------------------------------- [[alternative HTML version

Hello, I am using R 1.9.1 on Windows 2000 SP4. I have the following problem: Say I have a matrix, >my.matrix [,1] [,2] [,3] [1,] "A" "B" "C" [2,] "D" "E" "F" [3,] "G" "H" "I" I would like to apply an operation to this matrix which returns a list my.list containing the

useR's I have a matrix from which I want to take multiple subsets from, according to a particular scheme I will now describe. The matrix below (mat) is 5x5, and I want to take 9 subsets of it, each of dimension 3x3. The best way to explain what the result should look like is with the following: > dat <- c(3,6,1,9,12,9,2,10,6,5,3,13,1,4,8,9,4,6,10,11,2,7,3,5,10) > miss <-

Hi there Does anyone know, why this is not working?: par(mfrow = c(5, 5)) for (i in 1:10){ plot(x=time, y=Var.i) } (x-variable is time y-variable is Var out of matrix with columns Var.1 Var.2 Var.3 etc...) even for (i in 1:10){ plot(x=time, y=paste("Var", i, sep=".") } does not work Thanks marc

Hello I am able to extract partial regression coefficients from a fitted model object "model", i.e. model <- lm(var.sel.gkm, weights = count.gkm, data = DATA) summary(model) write.table(model$coef, file = "C:/coef_CO_gkm.txt", row.names = TRUE, col.names = TRUE) I was wondering if anyone could advise me how to extract other object items such as std. error, t-values

Hi Everybody, I have a matrix of about 45 columns. Some of the rows contain zeros. Using >data1<-data[complete.cases(data),], I can remove the "NA" rows. But I am unable to tackle that of zeros. Can anybody give me an idea of how to remove rows containing zeros in a matrix. Thanks so much Best Ogbos [[alternative HTML version deleted]]

Hi, I have a factor and I would like to find the most frequent level. I think my current approach is a bit long winded and I was wondering if there was a more elegant way to do it: x <- factor(sample(1:0, 5,replace=TRUE)) levels(x)[ which( as.logical((table(x) == max(table(x)))) == TRUE ) ] (The length of x will always be an odd number, so I wont get a tie in max()) Thanks,

Please, I would like to generate a random bistochastic matrix, that is a squared matrix of non-negative numbers with each row and each column sum to 1, for example : .2 .3 .5 .6 .3 .1 .2 .4 .4 I don't know of to code this. Do you have any idea ? Thanks Florent Bresson ___________________________________________________________________________ Demandez ?

Dear all I have data like this: x y [1,] 59.74889 3.1317081 [2,] 38.77629 1.7102589 [3,] NA 2.2312962 [4,] 32.35268 1.3889621 [5,] 74.01394 1.5361227 [6,] 34.82584 1.1665412 [7,] 42.72262 2.7870875 [8,] 70.54999 3.3917257 [9,] 59.37573 2.6763249 [10,] 68.87422 1.9697770 [11,] 19.00898 2.0584415 [12,] 60.27915 2.5365194 [13,] 50.76850

Hi, I have a correlation matrix of about 3000 items, i.e., a 3000*3000 matrix. For each of the 3000 items, I want to get the top 50 items that have the highest correlation with it (excluding itself) and generate a data frame with 3 columns like ("ID", "ID2", "cor"), where ID is those 3000 items each repeat 50 times, and ID2 is the top 50 correlated items with ID,

Dear all, I have a problem with the "subset()" function. I spent all day yesterday with a collegue to solve it and we did not find a satisfying solution (even in the archived mails), so I ask for your help. Let's say (for a simple example) a matrix mat: R> mat cola colb colc [1,] 1 4 7 [2,] 2 5 8 [3,] 3 6 9 My goal is to select the lines of the matrix on the basis of the

Hi all, Is it possible to add a permil (or per mille) symbol to an R plot (I couldn't find this symbol under demo(Hershey) or the plotmath information). In some ascii tables it is symbol no. 137. cheers, Matt. [[alternative HTML version deleted]]

How to do this in an elegant way formatrix/data frame/zoo? mat= 1 2 3 4 5 6 7 8 9 vector= 1 2 3 result= 0 1 2 2 3 4 4 5 6 ie 1-1 2-1 3-1 4-2 5-2 6-2 7-3 8-3 9-3 Thanks in advance. _________________________________________________________________ 08 [[alternative HTML version deleted]]

Hello UseRs: Excuses for my english. I have a dataset with 65000 records and I'd like to make a summary where I can view all the values (with the number of times that it repeats) that there are each column of my dataset. I tried with summary( ), str( ), but nothing gives me the result that I am loking for. Thank you very much.

Hello!!! I have a folder (C:/R/) with matrix files, named by number, i.e. 0.mat, 1.mat,...,1250.mat. In this case, they are 5x5 simetric matrices. I would like to compute a property for each matrix and put calculated values into a data frame for posterior ploting and printing. Below there is an example for 7 matrices (0.mat..6.mat) #define data frame L <- data.frame(frame=numeric(7),