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I'm running a long MCMC chain that is generating samples for 22 variables. I have each run of the chain as a row in a matrix. So: Chain[,1] is the column with all the samples for variable one. Chain[,2] is the column with all the samples for variable 2, etc. I'd like to fit all 22 on a single page to print a nice summary. It is OK if the graphs are small, I just need to show the

Hi, Our discussions about 64 bit R has led me to another thought. I have a nice dual core 3.0 chip inside my Linux Box (Running Fedora 11.) Is there a version of R that would take advantage of BOTH cores?? (Watching my system performance meter now is interesting, Running R will hold a single core at 100% perfectly, but the other core sites idle.) Thanks! -- Noah

Hi, I want to create variable names from within my code, but can't find any documentation for this. An example is probably the best way to illustrate. I am reading data in from a file, doing a bunch of stuff, and want to generate variables with my output. (I could make a "list of lists" and name all the elements, but I really want separate variables.) ################# #This is

Hi, I have a data.frame that I need to scale. I've been using the scale function and it works nicely. Some of the libraries I'm testing won't accept negative values for data, so I need to find a way to scale the data from 0 to 1 Any ideas? Thans!

Hi, I've been testing some models with the MCMCpack library. I can run the process and get a nice model "object". I can easily see the summary and even plot it. I can't seem to figure out how to: 1) Access the final coefficients in the model 2) Turn the coefficients into a model so I can then run predictions using them. A summary command will SHOW Me the coefficients, but

Hi, I have a strange one for the group. We have a system that predicts probabilities using a fairly standard svm (e1017). We are looking at probabilities of a binary outcome. The input data is generated by a perl script that calculates a bunch of things, fetches data from a database, etc. We train the system on 30,000 examples and then test the system on an unseen set of 5,000 records.

Hi, I need a bit of guidance with the sapply function. I've read the help page, but am still a bit unsure how to use it. I have a large data frame with about 100 columns and 30,000 rows. One of the columns is "group" of which there are about 2,000 distinct "groups". I want to normalize (sum to 1) one of my variables per-group. Normally, I would just write a huge

...er than by choosing from the predefined list.  The whole thing needs rewriting (and has for years), but that's certainly not something I'm planning to take on. Duncan Murdoch ------------------------------ Message: 41 Date: Sun, 30 Aug 2009 15:08:17 -0700 From: Noah Silverman <noah@smartmediacorp.com> Subject: [R] Sapply To: r help <r-help@r-project.org> Message-ID: <4A9AF851.5010709@smartmediacorp.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Hi, I need a bit of guidance with the sapply function.  I've read the help page, but am still a bit unsure ho...

Hi, Time for another of my "newbie" questions. Is it possible to build up a data.frame "row by row" as I go I'm going to be running a bunch of experiments (many in a loop) to test different things. I'm using AUC as my main performance measure. My thought was to add a row to a data.frame for each iteration and then have a nice summary report at the end. I found

Dear R People: I know that this is off topic, but could anyone recommend a good book on Linux scripting please? Any help would be much appreciated! Thanks, Erin -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: erinm.hodgess at gmail.com

Hi, I want to add a box at the bottom of a lattice window (device/page?). Lattice has drawn a nice group of panels with all the plots I need. How do I add my own summary text at the bottom (several lines worth?)

I'm reading Gellman's book "Data Analysis Using Regression and Multilevel-Hierarchical Models" In Chapter 7 (and later), he makes frequent referent to a function names "sim". I can't find the function anywhere, not in my standard R install, or in any of the packages. Doe anyone have a reference for this? Thanks!

Hello, I'm using the svm function from the e1071 package. It works well and gives me nice results. I'm very curious to see the actual coefficients calculated for each input variable. (Other packages, like RapidMiner, show you this automatically.) I've tried looking at attributes for the model and do see a "coefficients" item, but printing it returns an NULL result.

We're running Monte Carlo repeated measures for several groups. The goal is to determine the number of time each group has the highest score. A toy example: [,1] [,2] [,3] 0.1 0.2 0.3 0.1 0.2 0.3 0.1 0.2 0.3 0.1 0.3 0.2 0.1 0.3 0.2 0.2 0.3 0.1 For this example: group 1 was the top 0 times, group 2 was the top 3 times., group 3 was the top 3 times I can do

Hi, I have a process in R that produces a lot of output. My plan was to build up a matrix or data.frame "row by row", so that I'll have a nice object with all the resulting data. I started with: results <- matrix(ncol=3) names(results) <- c("one", "two", "three") Then, when looping through the data: results <- rbind(results, c(a,b,c))

Hi, I want to add a box at the bottom of a lattice window (device/page?). Lattice has drawn a nice group of panels with all the plots I need. How do I add my own summary text at the bottom (several lines worth?)

Hello, I need to build a "list of lists" We have 20 groups we are generating MCMC samples for. There are 10 coefficients, and 10000 MCMC iterations. I would like to store each iteration by-group in a list. My problem is with the first iteration. Here is a toy example: Chain <- list() for (j in 1:10000){ coef <- c(1,2,3,4,5,6,7,8,9,10) #would be actual MCMC samples

Hi, I am trying to figure out a "short" way to access two values output from the sort function. >x <- c(3,4,3,6,78,3,1,2) >sort(x, index.return=T) $x [1] 1 2 3 3 3 4 6 78 $ix [1] 7 8 1 3 6 2 4 5 It would be great to do something like this (doesn't work.): c(y, indexes) <- sort(x, index.return=T) But that doesn't work. I CAN grab the output of sort in a

Hi, I use the max function often to find the top value from a matrix or column of a data.frame. Now I'm looking to find the top 2 (or three) values from my data. I know that I could sort the list and then access the first two items, but that seems like the "long way". Is there some way to access "max_2" or similar? Thanks! -- Noah

Hi, I am reading in a dataframe from a CSV file. It has 70 columns. I do not have any kind of unique "row id". rawdata <- read.table("r_work/train_data.csv", header=T, sep=",", na.strings=0) When training an svm, I keep getting an error So, as an experiment, I wrote the data back out to a new file so that I could see what the svm function sees.