similar to: Coercing character to factor

I've been using the package rpart with R 1.3.0 for Windows to produce simple classification trees for some measurement data from paleontological specimens. Both the rpart documentation and the output confirm that the program produces splits on continuous data that leave "holes" in the data. It is probably of little practical importance, but is there a reason why the binary

I just updated rpart to the latest version (3.1.0). There are a number of changes between this and previous versions, and some of the code I've been using with earlier versions (e.g. 3.0.2) no longer work. Here is a simple illustration of a problem I'm having with xpred.rpart. iris.test.rpart<-rpart(iris$Species~., data=iris[,1:4], parms=list(prior=c(0.5,0.25, 0.25))) + ) >

I've been using rpart with R (1.3.0 Windows) for some time. I recently ran one of my research data sets through the rpart routine and produced a classification tree. I tried to replicate the results of the rpart analysis on another machine of mine and discovered some startling differences in the results. Puzzled, I went back to the raw data residing on both machines. I printed out

I'm graphing a series of boxplots of grouped data inside a function that passes the data.frame, the names vector, and a title vector. Because both the data subset changes with each successive pass through the function, occasionally the names vector turns up with only one group to plot. This is an expected result. However, when the names argument in boxplot has only a single name, it

I've created a bunch of postscript trees (post.rpart), which I subsequently edit in Adobe Acrobat 4.05 (I need additional labelling that isn't easy to add with R). After editing the labels and annotations using Acrobat, I then export the file to Adobe's .eps format so I can insert the picture into a Microsoft Word 2000 document. The .pdf file distilled from the .ps file is

I've run into another postscript/rpart problem unrelated to the issues I've mentioned in a previous query. I'm using 1.3.1 on a Win2K box. >plotcp(some.rpart.object) draws a very nice plot on the windows graphic device. If I save this as a postscript file, either by opening a postscript device before calling plotcp, or by saving the graphics window as a postscript file, the

I'm running a four-group, 15-variable discriminant analysis using the MASS function lda(). Discriminant functions 1 and 2 explain about 93% of the variance. I would like to plot the group scatters in a single scatterplot, identify each group's centroid, and encircle the group scatter with a 90% bivariate confidence ellipse. I can do this for each group on a separate plot, but I

At the risk of starting a holy war, I'd like opinions on the "best" current Linux distribution to run "out of box" with current versions of R. I note rpms for various versions of RedHat, SUSE, Mandrake, and Debian. I've had experience with RH 7.1 & 7.2 and it hasn't been entirely pretty. I understand that 7.3 is a bit "better", but have also

Before I reinvent the wheel, I have need for a relatively straightforward crosstabulation (2 x n) function. I know that R has table(), ftable(), xtabs(), and summary(xtabs()), but none of these produce a fully "tricked" out cross-tabulation with marginal totals, expected cell frequencies, and an array of statistics about the contingency table. Is there a more complete (something

>selectiris<-sample(1:5, 150, replace=T) > hist(selectiris, plot=TRUE) #freq=TRUE, breaks=5, etc all do the same thing >truehist(selectiris) Is the behavior of "hist" in this sample of code correct. On my system (Windows 2K, SP2) the first and second bars are pushed together, while the 3rd, 4th, and 5th bars are correctly positioned. The function "truehist"

David Brahm's initial post seems to me to be filled with a mixture of bugs, wants, and needs coupled with a desire to "make" R become S-Plus. David, if S-Plus works for you, why are you bothering to convert all your code to R? No one has ever asserted that R==S (or S-Plus), and there is no reason to expect this equality to hold, ever. R is open source. If you want to change

I'm running a series of simple bivariate linear regressions on grouped data. I want to test the slopes to see if they are parallel. I normally use analysis of covariance to do so, looking at interaction between the covariate and the factor to make this determination. VR3 pp.149 - 154 has a very nice example of an ANOCOVA, ending with a discussion of this very operation. My question has

Sorry for the uninformative subject. The following piece of code gives different output in S-Plus (2K & 6) vs R 1.2.1 (Win) apply(apehum[,6:15], 2, function(x) which(is.na(x))) S-Plus results: > apply(apehum[,6:15], 2, function(x) which(is.na(x))) $latsupri: numeric(0) $medepico: numeric(0) $pdhtcapi: numeric(0) $mlhtcapi: numeric(0) $aphttroc: [1] 151 152 $mlhttroc: numeric(0)

Hello. I have a hudge problem, don't know how to deal with it... I'm supposed to implement a tree structure in R, without using rpart library... I don't have any clue about appropriate approach... Anyway, I can't use pointers under R...so how to to it? lists, vectors... Anyway, does anybody knows how the regression tree in rpart was implemented... Someone please help! Thanks, ana

The question was: > I have this 'odd' problem; I need to let R pause, for a given time, before > starting next iteration in a loop. I'm using the following to do this > task, but feel a little bit guilty because I'm using as much CPU time as I > can get while pausing: > > while(keepGoing) { > t.end <- proc.time()[3] + 5 ## the time this loop should end

I have a matrix (1000 x 224) that contains the output from the function boot.array. For each row, there are 224 columns that represent the case numbers of the selected individuals from a bootstrap. The cases are listed in selection order, not numerical order. I'd like to rearrange the cells so that every row has the column entries listed ascending numeric order. I've been able to

I'm doing kmeans partitioning on a small (n=26) dataset that has 5 variables. I noticed that if I repeatedly run the same command, the cluster centers change and the cluster membership changes. Using RW1022 under Windows NT & Windows 2000 >kmeans(pottery[,1:5], 4, 20) [...snip] $size [1] 7 3 9 7 [...snip] $size [1] 7 10 4 5 [...snip] $size [1] 6 10 5 5 yields a different

I'm trying to develop a systematic way of placing legends on (among other things) scatterplots of grouped data. The journals in my field can be very fussy about the placement of figure legends. Typically they want them to be in either of two places - the upper left corner of the plotting area, not obscuring any data points, or outside the plotting area in the lower right hand corner of

I'm not really sure this is the place to raise this, but here goes anyway. I've downloaded the 1.4.0 recommended package sources R-1.4.0-recommended.tgz multiple times from the main CRAN site. The sources have arrived corrupted each time (from multiple computers BTW). If I download the same file from the UCLA or University of Bristol mirror, I also get corrupt archive files. On the

Hi, I have a problem with R-devel and Stataread 2.5. Stataread installs (compiles, at gives no error messages). But typing > library(stataread) Error in dyn.load(x, as.logical(local), as.logical(now)) : unable to load shared library "/usr/local/lib/R/library/stataread/libs/stataread.so": /usr/local/lib/R/library/stataread/libs/stataread.so: undefined symbol: errorcall Error in