similar to: Making routine faster by using apply instead of for-loop

Dear R-Users, I'm relativley new to R and have the following problem. I need all permutations of the vectors created by the collumns of a matrix. I will give a small example: p=3 n=2^p-1 #number of obtainable vectors mat=matrix(0,p,p) for(i in 1:p) { mat[i:1,i]=1/i } mat is now a

Hey everybody, I have a problem with the combination of the commands outer() and predict(). I want to visualize the solutions of a regression modell in a matrix. Therefore I want to use the command predict for a linear modell as the function inside the command outer. I've made a small example: x = 1:10 y = 11:20 z = rnorm(10) lm.1 = lm(z ~ x*y)

Hi everybody, I'm trying to build a trilineare coordinate system with R. For that, I need to rotate an axis. Does anybody know, if it is possible to rotate an axis, created with the command axis(), about for instance 60 degrees? I'm looking foward to any ideas and hints and want to wish everybody a merry merry christmas. Thanks in advance. Etienne Stockhausen

Dear R-User, I'm trying to visualize the results of the power calculation with the function power.t.test(). Therefore I want to plot the related t-distributions and shade the surfaces indicatingt the type I error, the type II error and the power. For sample sizes greater 30 I got results which are very satisfying. For small sample sizes I got stuck and did'nt find a mistake. To show you

Hello everybody, I'm trying to use a if-statment on a function. For a better understanding I want to present a small example: FUN=mean # could also be median,sd or any other function if (FUN == mean) plot(...) if (FUN == median) plot(...) ... This doesn't work, because FUN is a function. I've already tried to coerce the

Good afternoon everybody, I'm writing a little function to visualise hypothesis testing. Therefore I need to extract the confidence level of a t-test. Here a little example: x <- str(t.test(1:10) gives List of 9 $ statistic : Named num 5.74 ..- attr(*, "names")= chr "t" $ parameter : Named num 9 ..- attr(*, "names")= chr

Ein eingebundener Text mit undefiniertem Zeichensatz wurde abgetrennt. Name: nicht verf?gbar URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20110329/ec6a4e5d/attachment.pl>

Hi R community, I have a question concerning passing arguments between apply and lapply? Or maybe, once my problem is explained, the question is really about how to best transform my nested for loops into list/matrix operations; I am just beginning this transformation away from nested for loops, so I beg of you to have some lenience regarding my ignorance. Part I: I used a set of nested for

I have tried a lot of ways around this, but I can't find a way to make apply work in a generalized way because it causes a failure whenever reduces the dimensions of its output. The following example is easier to understand than the question. I wish it had a "drop=TRUE/FALSE" option like the "[" (and I wish I had found the drop option a year ago, and I wish that I had 1e6

Ein eingebundener Text mit undefiniertem Zeichensatz wurde abgetrennt. Name: nicht verf?gbar URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20101108/60bbf91d/attachment.pl>

Dear all, Indexing matrices from the Matrix package with [i,j] seems to be very slow. For example: library(rbenchmark) library(Matrix) mm <- matrix(c(1,0,0,0,0,0,0,0), nr=20, nc=20) MM <- as(mm, "Matrix") lookup <- function(mat){ for (i in 1:nrow(mat)){ for (j in 1:ncol(mat)){ mat[i,j] } } } benchmark(lookup(mm), lookup(MM),

Hello everyone, Considering the following code sample : ---- indexes <- function(vec) { vec <- which(vec==TRUE) return(vec) } mat <- matrix(FALSE, nrow=10, ncol=10) mat[1,3] <- mat[3,1] <- TRUE ---- Issuing apply(mat, 1, indexes) returns a 10-cell list, as expected. Now if I do: ---- mat[1,3] <- mat[3,1] <- FALSE apply(mat, 1, indexes) ---- I would expect a

Dear R-help, I have been trying really hard to generate the following vector given the data (x) and parameter (alpha) efficiently. Let y be the output list, the aim is to produce the the following vector(y) with at least half the time used by the loop example below. y[1] = alpha * x[1] y[2] = alpha^2 * x[1] + alpha * x[2] y[3] = alpha^3 * x[1] + alpha^2 * x[2] + alpha * x[3] ..... below are

I have a function that I am currently using very inefficiently. The following are needed to illustrate the problem: set.seed(12345) dat <- matrix(sample(c(0,1), 110, replace = TRUE), nrow = 11, ncol=10) mis <- sample(1:110, 5) dat[mis] <- NA theta <- rnorm(11) b_vector <- runif(10, -4,4) empty <- which(is.na(t(dat))) So, I have a matrix (dat) with some values within the matrix

Greetings, My goal is to create a Markov transition matrix (probability of moving from one state to another) with the 'highest traffic' portion of the matrix occupying the top-left section. Consider the following sample: inputData <- c( c(5, 3, 1, 6, 7), c(9, 7, 3, 10, 11), c(1, 2, 3, 4, 5), c(2, 4, 6, 8, 10), c(9, 5, 2, 1, 1) ) MAT <- matrix(inputData,

Dear list, I am a little confused as to when to use apply, sapply, tapply, vapply, replicate. I've encountered this several times, This is time, this is what I am working on, mat <- matrix(c(seq(from=1, to=10), rnorm(10)), ncol=2) a=1; b=5 newfun <- function(x, y, a, b) { x*y+a+b } sapply(i=1:10, newfun(x=mat[i, 1], y=mat[i, 2], a=a, b=b)) Error in match.fun(FUN) : argument

Hi all, I have a question about apply function. Is that possible to pass some non-default arguments in the function we want to apply ? For example: if "mat" is a matrix and I want to use the "tabulate" function on its row. The command apply(mat,1,tabulate) works but I have problem with this one apply(mat, 1, tabulate(nbins=4)). Any clue ? Thanks, Eric -- Eric

Hi, this is a made-up example. Function "myfun" returns two arguments. Can "apply" be used so that "myfun" is called only once? Thanks Serguei mat<-matrix(runif(50),nrow=10,ncol=5) myfun<-function(x) { mymean<-mean(x) mysd<-sd(x) return(mymean,mysd) } out1<-t(apply(mat,1,function(x) myfun(x)$mymean)) out2<-t(apply(mat,1,function(x)

Hi everyone I'm trying to use sigma2.mat<-apply(ri.mat,2,'-n/2*log(sum(ri.mat^2)/n)') but it's not working. Is it wrong to use that kind of FUN in apply ? or am I doing something wrong ?! Thank's ernesto -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send

I know this is a simple question, but I have yet to master the apply statements. Any help would be appreciated. I have a column of probabilities and sample sizes, I would like to create a column of binomial random variables using those corresponding probabilities. Eg. mat = as.matrix(cbind(p=runif(10,0,1), n=rep(1:5))) p n [1,] 0.5093493 1 [2,] 0.4947375 2 [3,]