similar to: Creating and Using Objects in R

Dear All, I need to plot some points on the surface of a sphere, but I am not sure about how to proceed to achieve this in R (or if it is suitable for this at all). In any case, I am not looking for really fancy visualizations; for instance you can consider the images between formulae 5 and 6 at http://bit.ly/hOgK9h Any suggestion is appreciated. Cheers Lorenzo

Hallo, I have a set of S4 and S3 classes together in one script. While running this script I create a lot of new functions and objects An example for S3 and S4 classes: ## S3 classes pt <- list(x=1,y=2) class(pt) <- "xypoint" xpos <- function(x, ...) UseMethod("xpos") xpos.xypoint <- function(x) x$x ypos <- function(x, ...) UseMethod("ypos")

Dear R-users, Hereby a polar plot function for plotting angular data. I hope it will be usefull for some of you. I had a need to plot frequencies of wind-directions. The not-that-cheap SigmaPlot software did not allow me to change the orientation of the angular axis to clockwise orientation (what is used for meteorological observations). I even tried the latest version availible at the time

Dear All, I implemented an algorithm for (uniform) random rotations. In order to test it, I can apply it to a unit vector (0,0,1) in Cartesian coordinates. The result is supposed to be a set of random, uniformly distributed, points on a sphere (not the point of the algorithm, but a way to test it). This is what the points look like when I plot them, but other then eyeballing them, can anyone

Hello All, I am attempting to use the feather.plot function from the plotrix package to graph current velocity data as I have speed and direction. I let "r" be the first 10 rows of current speed data and "theta" be the first 10 rows of directional data in radians. I had tried this with 10 measurements, but keep getting the following error message: >

Dear All, I am trying to fit some data both as a negative binomial and a zero inflated binomial. For the first case, I have no particular problems, see the small snippet below library(MASS) #a basic R library set.seed(123) #to have reproducible results x4 <- rnegbin(500, mu = 5, theta = 4) #Now fit and check that we get the right parameters fd <- fitdistr(x4, "Negative

Kia Ora > Although I'm not sure what problem it would solve... Given that you asked, I was interested in writing a multiple assignment function as a replacement function, so something like: massign (x, y, z) = construct.some list () Obviously, that's not possible. Probably the best example I can think of is converting cartesian coordinates to polar coordinates. Then we might have

Hi Ralf, I tried the following > install.packages("RCurl") which went OK, but then same story when I tried to install tseries. > sessionInfo() R version 3.6.1 (2019-07-05) Platform: x86_64-pc-linux-gnu (64-bit) Running under: Debian GNU/Linux 10 (buster) Matrix products: default BLAS: /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.8.0 LAPACK:

Dear All, I am far from being a guru about parallel programming. Most of the time, I rely or randomForest for data mining large datasets. I would like to give a try also to the gradient boosted methods in GBM, but I have a need for parallelization. I normally rely on gbm.fit for speed reasons, and I usually call it this way gbm_model <- gbm.fit(trainRF,prices_train, offset = NULL, misc =

Dear All, Probably a one liner, but I am banging my head against the floor. Consider the following DF <- data.frame( x=1:10, y=10:1, z=rep(5,10), a=11:20 ) mn<-names(DF) but then I cannot retrieve a column by doing e.g, DF$mn[2] I tried to play with the quotes and so on, but so far with no avail. Any suggestion is welcome. Cheers Lorenzo

Dear All, I am learning the ropes about logistic regression in R. I found some interesting examples http://bit.ly/Vq4GgX http://bit.ly/W9fUTg http://bit.ly/UfK73e but I am a bit lost. I have several questions. 1) For instance, what is the difference between glm.out = glm(response ~ poverty + gender, family=binomial(logit), data=mydata) and glm.out = glm(response ~ poverty * gender,

Dear All, I would like to be able to plot histograms/densities on a semi-log or log-log scale. I found several suggestions online http://tolstoy.newcastle.edu.au/R/help/05/09/12044.html https://stat.ethz.ch/pipermail/r-help/2002-June/022295.html http://www.harding.edu/fmccown/R/#histograms Now, consider the code snippet taken from http://www.harding.edu/fmccown/R/#histograms # Get a random

Dear All, I am struggling with the following problem: I am given a NxN symmetric matrix P ( P[i,i]=0, i=1...N and P[i,j]>0 for i!=j) which stands for the relative distances of N points. I would like use it to get the coordinates of the N points in a 2D plane. Of course, the solution is not unique (given one solution, I can translate or rotate all the points by the same amount and generate

Apologies for the previous mail (I sent it off too early by mistake). This is the correct example: rm(list=ls()) D_mean<-seq(-5,5,length=100) y<-exp(-D_mean^2/5) pdf("my.pdf") plot(D_mean,y,type="l",yaxt="n",lty=2,lwd=2,col="black", ylab = list(expression(paste(dN/dlogD[agg]," ["*cm^-3*"]"))), xlab = expression(paste(D[agg],"

Dear All, I am given some data to analyze. The data is in the form of a Stata database (.dta file). What is the best way to import it into an R dataframe? Is there any particular caveat I should be aware of? Many thanks Lorenzo

Dear All, Probably something very easy, but I am looking for the most efficient ways to achieve this. Consider the following snippet y<-c('a','b','c','d','e','f','g') x<-rnorm(length(y)) df<-data.frame(y,x) leading to > df$y [1] a b c d e f g Levels: a b c d e f g Now, I would like to replace levels

I thought about that star graph again, and realized that it would be quite a handy thing for visualizing cyclic data like time or compass direction. Here is a cleaned up (and renamed) version to do a polar plot that starts at the right and goes counterclockwise or a 24 hour clock plot that starts at the top and goes clockwise. There are probably other varieties that would be interesting. Jim

Dear All, I would like to use a randomForest algorithm on a dataset. The set is not particularly large/difficult to handle, but it has some missing values (both factors and numerical values). According to what I found https://stat.ethz.ch/pipermail/r-help/2005-September/078880.html https://stat.ethz.ch/pipermail/r-help/2007-January/123117.html the randomForest package has a problem with missing

Dear All, I have never had this problem before. I run debian testing on my box and I have recently update my R environment. Now, see what happens when I try the most trivial of all plots > plot(seq(22)) Error in (function (display = "", width, height, pointsize, gamma, bg, : X11 module cannot be loaded In addition: Warning message: In (function (display = "", width,

Dear All, Consider a matrix (N x N) where each entry is either zero or one (can hardly get any simpler). Now, I would like to plot it as a 'chessboard' where every matrix entry is a black (1) or white (0) square. Whatever tool I use to plot it, it should not try to interpolate the data at all. I found some online references http://www.phaget4.org/R/image_matrix.html but probably I can