similar to: Read every second line from ASCII file

Recently I came across an interesting web site: http://portableapps.com/. The idea is simple, this is software that is possible to install and run on some type of USB memory, a stick or one of these hard disks. I can think of a number of situations where this could be handy. In addition memory sticks are getting cheaper and more powerful by the day. So: Is it possible to run R off one of

Hello all I''ve just installed xen 4.1.1 on my server and was tryoing to tweak xendomains script to work with new xl schema but I can´t get it to save domains. It does start them with some changes I made to it but when I issue service xendomains stop I just get [ OK ] but domains stay running. Has xendomains script been ported to work with 4.1.1 or is there another alternative to it.

Dear all, I have several datasets and I want to generate pdf plots from them. I also want to generate automatically the names of the files. They are country-specific and the element mycurrentdata[1,1] contains this information. So what I do is something like this: pdf(file=paste(mycurrentdata[1,1], ".pdf", sep=""), width=...etc) The only problem I have is that some of the

Dear lists, any suggestion on how to write a function to return a TRUE if interval [a,b] overlaps the interval [c,d]. I've tried it but an error occur saying that 'could not find function v ; in addition warning message occur'. Below is my codes.Please help me sort this problem as i'm in process of learning of writing a function. Many thanks overlap<-function(m,n){

Dear R-Helpers, I have a matrix where the first column is known. The second column is the result of multiplying this first column with a constant "const". The third column is the result of multiplying the second column with "const"..... So far, I did it like this (as a simplified example): nr.of.columns <- 4 myconstant <- 27.5 mymatrix <- matrix(numeric(0), nrow=5,

Dear all, I have a population with three age-classes, at time t=0 the population is: n.zero <- c(1,0,0) I have a transition matrix A which denotes "fertility" and "survival": A <- matrix(c(0,1,5, 0.3,0,0, 0,0.5,0), ncol=3, byrow=TRUE) To obtain the population at t=1, I calculate: A %*% n.zero To obtain the population t=2, I calculate: A %*% (A %*% n.zero) ... and so

Dear all, I would like to put two perspective plots into one plot. The help page for ?persp shows how one can add points and lines but not another perspective plot. data(volcano) z <- 2 * volcano # Exaggerate the relief x <- 10 * (1:nrow(z)) # 10 meter spacing (S to N) y <- 10 * (1:ncol(z)) # 10 meter spacing (E to W) ## Don't draw the grid lines : border = NA persp(x,

I?m trying to find datasets that will give me residuals, after applying the lm function, with no normality, non linearity, and heteroscedacity so I can try to exemplify those cases in the linear regression model. Can you give any advice on what datasets would be appropiate? I can?t use the ones in the alr3 package because those have already been seen in class. Thank you very much :-) natorro

I've ported somebody else's rather cumbersome Matlab model to R for colleagues that want a free build of the model with the same type of I/O. The Matlab model reads a text file with the initial parameters specified as: C:\Data\Carluc\Rport>more Params.R # Number of years to simulate nYears = 50; # Initial year for graphing purposes year0 = 1970; # NPP/GPP ratio (cpp0 unitless) fnr =

Dear all, is there a possibility to display pictures (jpegs, pngs, ...) in R? Maybe the following (hypothetical) code makes it clearer what I have in mind: plot(x=0:100, y=0:100, type="n") rect(xleft=25, xright=75, ybottom=30, ytop=95, fill="apicture.png") Thank you, Roland [[alternative HTML version deleted]]

Dear All, yesterday I took the R-1.8.0-source file and compiled it on my own. As I am using Linux just for a couple of weeks, it was my first compiling session with ./configure, make, .... Everything went fine, except for one thing: if I want to look at the commands history by using the cursor keys, it does not work. Instead of displaying the previous commands, it returns something like

If we use the ROCR package to find the accuracy of a classifier pred <- prediction(svm.pred, testset[,2]) perf.acc <- performance(pred,"acc") Do we?find the maximum accuracy?as follows?(is there a simplier way?): > max(perf.acc at x.values[[1]]) Then to find the cutoff point that maximizes the accuracy?do we do the following?(is there a simpler way): > cutoff.list <-

Dear R-Users, given you have been teaching R to students (grad level, mainly social science background, no previous programming experience, 80% know SPSS), what are your experiences concerning the style of teaching? Do you prefer to stand in front of the class like in "normal" lectures and you show them slides? Or do you you explain some concept (for example things like

Dear all, let's assume I have a vector of character strings: x <- c("abcdef", "defabc", "qwerty") What I would like to find is the following: all elements where the word 'abc' does not appear (i.e. 3 in this case of 'x'). Since I am not really experienced with regular expressions, I started slowly and thought I find all word were

Dear all, given I have data in a data.frame which indicate the number of people in a specific year at a specific age: n <- 10 mydf <- data.frame(yr=sample(1:10, size=n, replace=FALSE), age=sample(1:12, size=n, replace=FALSE), no=sample(1:10, size=n, replace=FALSE)) Now I would like to make a matrix with (in this simple example) 10 columns (for the

Dear All, I have these data: exampledata <- c("This is one item", "This is Another One", "And so is This") I would like to find each occurence of a blank space followed by a Capital Letter and replace it by a blank space, a left curly brace, the respective Capital Letter, and then a right curly brace. I thought the following will do: gsub(pattern = "

Dear R-Users, I want to ask a question for a colleague of mine. He wants to put a character vector and a numeric vector into one matrix and still have the old character and numeric type for the respective columns. Unfortunately, I am just starting using R and I could not help him. Is there an easy and straightforward way to do this in R? Maybe a little example facilitates understanding our

Hi everyone, I have a matrix that has a combination of zeros and NAs. When I perform certain calculations on the matrix, the zeros generate "Inf" values. Is there a way to either convert the zeros in the matrix to NAs, or only perform the calculations if not zero (i.e. like using something similar to an !all(is.na() construct)? Thanks, rcoder -- View this message in context:

Dear all, I wanted to make a two-way-table of two variables with a counting variable stored in another column of a dataframe. In version 1.9.1, the behavior is as expected as shown in the simplified example code. > sex <- rep(c("F", "M"), 5) > income <- c(rep("low", 5), rep("high", 5)) > count <- 1:10 > mydf <-

Dear all, I would like to plot the dagger symbol in R (like LaTeX's \dagger). However, I was unable to do so. First, I thought maybe dagger actually exists just like the degree symbol: plot(0:1,0:1, type="n") text(x=0.5, y=0.5, labels=expression(degree)) plot(0:1,0:1, type="n") text(x=0.5, y=0.5, labels=expression(dagger)) However, this was not very successful. New