similar to: Merging nested lists

Dear List, Let's say I have a list whose components are 2 matrices (as exemplified in the "mylist" object below). I'd like to create a list with components being 4 matrices based on an logical index vector. is there a way to simplify what I'm doing to obtain the results in "mylist2"? I'd like something that would work on an arbitrary number of elements in

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?

|Hello, Given a function with several arguments, I would like to perform an lapply (or equivalent) while holding one or more arguments fixed to some common value, and I would like to do it in as elegant a fashion as possible, without resorting to wrapping a separate wrapper for the function if possible. Moreover I would also like it to work in cases where one or more arguments to the original

Greetings, I need to compare the ratios of vector sizes like this: length(object1) / length(object2) I have many vector objects to compare, so I would like to do it in a loop. I created a loop like this: mat1 <- matrix() for (i in 1:6) { for (j in 1:6) { mat1[i,j] <- length( paste("object",i,sep="")) /

Hi, everybody: I asked about this in r-help last week and promised a summary of answers. Special thanks to the folks that helped me understand do.call and pointed me toward plyr. We face this problem all the time. A procedure generates a list of data frames. How to stack them together? The short answer is that the plyr package's rbind.fill method is probably the fastest method that is not

hello all, thank you for taking the time I have a matrix A that have column names (let say n columns), I want to reduce the matrix to have just a few of those column (p colums, this is trivial), but for the lines I want only the lines such that A(i,J) is part of a list (J is fixed and known) I am sure it is very easy but I don't find it (I tryed which but it doesn't seem to work) Surely

Hello I want to unlist the attached element getting only the first element in each element of the list. The last element of the list looks as this: [[5065]] [[5065]]$Pluv3Meses [1] 274.4 [[5065]]$PluvMesesMedio [1] 378.2667 [[5065]]$Pluv2UltimosMeses [1] 23.33333 So I would like to get for each element of the list the element called Pluv3Meses. The whole list has 5065 elements but when I try to

Hi there, I have a list of dataframes (generated by reading multiple files) and all dataframes are comparable in dimension and column names. They also have a common column, which, I'd like to use for merging. To give a simple example of what I have: df1 <- data.frame(c(LETTERS[1:5]), c(2,6,3,1,9)) names(df1) <- c("pos", "data") df3 <- df2 <- df1 df2$data

Hello I tried to define replacement functions for the class "mylist". When I test them in an active R session, they work -- however, when I put them into a package, they don't. Why and how to fix? make_my_list <- function( x, y ) { return(structure(list(x, y, class="mylist"))) } mylist <- make_my_list(1:4, letters[3:7]) mylist mylist[['x']] <- 4:6

I can define a list containing NULL elements: > myList <- list("aaa",NULL,TRUE) > names(myList) <- c("first","second","third") > myList $first [1] "aaa" $second NULL $third [1] TRUE > length(myList) [1] 3 However, if I assign NULL to any of the list element then such element is deleted from the list: > myList$second <-

Hi, I'm pretty new to R. I have an object (say a list) and I I have a function that I call on various columns in that list (excuse terminology if it's wrong/ambiguous). Imagine its like this (actual values are unimportant) and called mylist: >mylist A B 1 5 2 5 3 6 4 8 5 0 I have a function: foo = function(param){ #modify list A or B values depending on

Hi, I'm have a list of integer vectors and I want to perform an outer() like operation on the list. As an example, take the following list: mylist <- list(1:5,3:9,8:12) A simple example of the kind of thing I want to do is to find the sum of the shared numbers between each vector to give a result like: result <- array(c(15,12,0,12,42,17,0,17,50), dim=c(3,3)) Two for() loops is the

Hi I have a list : mylist <- list( a = NULL, b = 1, c = 2 ) > mylist[1] $a NULL > is.null(mylist[1]) [1] FALSE > is.null(mylist$a) [1] TRUE why? I need to use mylist[1]

I have this awkward problem with trellis (lattice). I am trying to generate some plots through loops but the .eps file is empty. When I generate them in a list and print them outside the loop all is fine. this is an example below:( nothing shows up in foo.eps, but all show up in foo1.eps) R vesion 2.0.1, lattice version 0.10-16, on a debian 2.6.8-1 kernel. X <- data.frame(x=rnorm(10000),

How do I parse an identifier of a list component, e.g. mylist$mycomponent or mylist[[1]] ? Parse does not do the job, e.g. parse(text="mylist$mycomponent") returns an expression with just one term, instead of "mylist", "$", "mycomponent". What I need is a way to extract the list name (e.g. "mylist"), given an identifier of a component.

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

Sorry My previous report is not detailed. In R, you will get this: > mylist <- list() > mylist[[1]] Error in mylist[[1]] : subscript out of bounds > mylist[[1]] <- c(1) Error: (list) object cannot be coerced to vector type 14 > mylist[[1]] <- c(1,2) > mylist[[1]] <- c(1) > mylist [[1]] [1] 1 I was trying to assigning c(1) to (mylist[[1]] <- c(1)) -- it seems

Excuse me for what I'm sure is a stupid beginner's question, but I've given up trying to find the answer to this question from the help, RSiteSearch, or any of the usual places. I have a list that looks like this: >myList $first [1] "--" "18" "8" "32" $second [1] "--" "--" "40" "54" I want a

Dear R-Helpers, I have a list l1 like: l1[[1]] a b c l1[[2]] d l1[[3]] e f I want an output res like: res[[1]] 1 1 1 res[[2]] 2 res[[3]] 3 3 Essentially, I want to replicate each index equal to the number of elements present in that index. Below is what I do to accomplish this: l1 <- list(c("a", "b", "c"), "d", c("e", "f"))

Hi, Try > is.null(mylist[[1]]) [1] TRUE Notice the double square brackets. From: ?`[` "The most important distinction between [, [[ and $ is that the [ can select more than one element whereas the other two select a single element." On Thu, Jun 15, 2017 at 11:33 AM, ce <zadig_1 at excite.com> wrote: > Hi > > I have a list : > > mylist <- list( a = NULL, b