similar to: how to convert list into a vector

Hi, I'm having difficulty importing my textfile that looks something like this: #begin text file Timepoint 1 ObjectNumber Volume SurfaceArea 1 5.3 9.7 2 4.9 8.3 3 5.0 9.1 4 3.5 7.8 Timepoint 2 ObjectNumber Volume SurfaceArea 1 5.1

Hi guys, here is a list of names that I have: MyList: > myList<-list("A", "B","C","D") > myList [[1]] [1] "A" [[2]] [1] "B" [[3]] [1] "C" [[4]] [1] "D" I want to turn this list into a matrix of 1 row and 4 columns with those four components (A, B, C, D) so here is what I do: myDataFrame <-

I have a set of character vectors of uneven length that I have stored in a list. I can easily enough get any column of them using lapply but what I want is to be able to create a matrix of them. Other than some kind of brute force looping approach I have drawn a blank. Would somebody please suggest something? Thanks Example. mylist <- list(aa=c("cat","peach" ),

Hi We have touched on this before, but I don't think I quite got it right. So I have a list, each element of which is a a vector of 2 numbers: > l2 $cat000_a01 [1] 0.3429944 4.5138244 $cat000_a02 [1] 0.1929336 4.3064944 $cat000_a03 [1] -0.2607796 4.1551591 What I actually want to convert this into is a matrix with the names (cat000_a01 etc) as row names, the first element of each of

Dear all, I think that my question is very simple but I failed to solve it. I have a list which elements are matrices like this: >mylist [[1]] [,1] [,2] [,3] [1,] 1 3 5 [2,] 2 4 6 [[2]] [,1] [,2] [,3] [1,] 7 9 11 [2,] 8 10 12 I'd like to create a matrix M<-mylist[[1]]+mylist[[2]] [,1] [,2] [,3] [1,] 8 12 16 [2,] 10 14 18

I've been doing some consulting with students who seem to come to R from SAS. They are usually pre-occupied with do loops and it is tough to persuade them to trust R lists rather than keeping 100s of named matrices floating around. Often it happens that there is a list with lots of matrices or data frames in it and we need to "stack those together". I thought it would be a simple

Hello! # I have a list with several data frames: mylist<-list(data.frame(a=1:2,b=2:3), data.frame(a=3:4,b=5:6),data.frame(a=7:8,b=9:10)) (mylist) # I want to grab only one specific column from each list element neededcolumns<-c(1,2,0) # number of the column I need from each element of the list # Below, I am doing it using a loop: newlist<-NULL for(i in 1:length(mylist) ) {

I have a list that is made of lists of varying length. I wish to create a new vector that contains the last element of each list. So far I have used sapply to determine the length of each list, but I'm stymied at the part where I index the list to make a new vector containing only the last item of each list mylist =

Hello guys, I am working on a matrix which looks like this one: > initialMatrix <- > rbind(cbind(rep("A",3),seq(1,3)),cbind(rep("B",4),seq(1,4)),cbind(rep("C",3),seq(1,3))) > initialMatrix [,1] [,2] [1,] "A" "1" [2,] "A" "2" [3,] "A" "3" [4,] "B" "1" [5,]

I'll appreciate your help on this. I have values stored in a list as in "mylist" below. I need to sum the values over all elements of the list aggregated by the names of the matrices. mylist <- list(matrix(c(0.2, 0.4), 1, 2, dimnames = list(NULL, c("1", "2"))), matrix(c(0.1, 0.5), 1, 2, dimnames = list(NULL, c("1",

Dear People, I have got the following example for a vector and the index of the TRUE element: Myvector <- c(FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,TRUE) which(Myvector) Now I would like to find out the same for a list: Mylist <- list(FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,FALSE,TRUE) ... Does anyone know how to do this? Thank you very much in advance, Marion [[alternative HTML

Hi R -users, i've a table as describe below. I'm reading the numeric value presented in this table to populate a list. #table #============ #X    A    B    C #x1    2    3    4 #x2    5    7    10 #x4    2    3    5 #============ rawData <- read.table("raw_data.txt",header=T, sep="\t") myList=list() counter=0 for (i in c(1:length(rawData$X))) {     print (i)    

I am looking for a function to flatten a list to a list of only 1 level deep. Very similar to unlist, however I don't want to turn it into a vector because then everything will be casted to character vectors: x <- list(name="Jeroen", age=27, married=FALSE, home=list(country="Netherlands", city="Utrecht")) unlist(x) This function sort of does it: flatlist

Hi Im pretty new to R and I have run in to a problem. How do I name all the levels in this list. Lev1 <- c("A1","A2") Lev2 <- c("B1","B2") Lev3 <- c("C1","C2") MyList <- lapply(Lev1,function(x){ lapply(Lev2,function(y){ lapply(Lev3,function(z){ paste(unlist(x),unlist(y),unlist(z)) })})}) I would like to name the different

I have a matrix of data. I need to scan the matrix and find every sequence from maxima to maxima across a row. I can write a loop to do this easily. Problem is, I can't figure out how to store the results. Each result is a vector of widely varying lengths. Ideally I'd like a vector of these, i.e. a vector of vectors, so I can quickly iterate through them and compute correlation

What is the right way to assign a new variable into each a of list of data frames? Here is my failed attempt: mylist <- list(df1 = data.frame(A = runif(5), B = runif(5)), df2 = data.frame(A = runif(5), B= runif(5))) lapply(mylist, function(x){x$Y <- x$A * x$B}) $df1 [1] 0.25589928 0.03446026 0.94992362 0.21388326 0.08668821 $df2 [1] 0.08771839 0.05643553 0.09036894

hello everybody, i have got a question about lists: i have got the following commands: mylist <- list("v1"=c(1,2,2,1),"v2"=c(2,2,2,1),"v3"=c(1,1,1,1)) myvector <- c(100,10000,1000000) now i would like to multiply each element of the list with the corresponding element of the vector, that is to say: v1*100 v2*10000 v3*1000000 i only could think of lapply

Dear R-Helpers, I have the following code: data = read.csv("test.csv",header=T,na.strings="-",row.names=1) myData=as.matrix(data) ##myData is a 102x19 matrix myList = alply(myData, 2,function(x){matrix(x,ncol=6,byrow=T)}) ##myList is a list containing 19 matrices with the following names > names(myList) [1] "*ES" "*ET" "*ER"

Hi all, I have a list of vector of numbers - the reason I used list of vector was that I each list have different numbers of numbers which I don't know before run-time. mylist[[1]] = c(1, 2, 3) mylist[[2]] = c (3, 4, 5, 6) ... ... etc. Could you please tell me if there is a way to dump all these at once into csv file such that each row correspond to a vector or a cell of the list as shown

Dear R users, Let's say I have a list with components being 'm' matrices (as exemplified in the "mylist" object below). Now, I'd like to subset this list based on an index vector, which will partition each matrix 'm' in 2 sub-matrices. My questions are: 1. Is there an elegant way to have the results shown in mylist2 for an arbitrary number of matrices in mylist?