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Hi all, I was wondering whether it is possible to plot math functions, for example sin, cos or a Gaussian type function, in R, and if so, how to do it. I have been searching through the archives and the...

Hi all, I'm currently working with a dataset that has quite a few missing values and after some investigation I figured that multiple imputation is probably the best solution to handle the missing data in my case. I found...

Hi all, I have a question about the SOM routine. You can either supply the initial representatives for the lattice yourself or else they are chosen randomly from the dataset. Is it possible to pass the random-seed as an...

Hi all, Recently I have written a small application, SOMviewer, that is able to graphically display a self organizing map produced with the som algorithm found in the GeneSOM package, clustered by any hierarchical clustering method that produces a merge...

Hello dear R-list members, I have a question about normalizing data. The goal is to normalize the dataset per column, so all the data in each column is scaled to the interval (0,1), will have a mean of...

Hi all, I am running a series of experiments where after manipulating my data I run several clustering algorithms (agnes, diana and a clustering method of my own) on the data. I wanted to determine which clustering method did the...

Hello everyone, I'm new to this list, so let me introduce myself: my name is Jonck van der Kogel and I am a graduate student at the Erasmus University of Rotterdam. I am currently working on my thesis which...

Hi all, I have (yet another) question about a function in R. What I would like to do is test for the presence of a certain value in a vector, and have the positions that this value is at returned...

Hi Ian, Not 100% sure on this, but I've recently been wrestling with producing plots in R and I think I know the answer to your question. As far as I could tell, all the parameters for graphics are...

Hi all, I am having a bit of trouble with the array structure of R. What I want to do is dynamically add/remove elements to an array. For example: Let's say I have created an array: > myArray <- array...

Hi, Maybe I'm not understanding you correctly, but wouldn't the following be the fastest way to compute the sum of a column: > x <- matrix(c(1:4462), nrow=4462, ncol=1) #setting up a column of 4462 elements...

Hi all, I am momentarily experimenting with Silhouette from the cluster library but I am getting some errors. Since Silhouette can be seen as a quality measure for a clustering what I want to do is run a series of...

Hi all, A short while ago I asked a question about multiple imputation and I got several helpful replies, thanks! I have untill now tried to use the packages mice and norm but both give me errors however. mice does...