search for: infirmari

Hi Helpers, Does anyone know how to read jpeg, bmp or png files into R? I have some photos of brain scans and I want to quantify some aspects of their size. I might be able to do this with the 'locator' function, if I could figure out how to read the files in and make them into an image that I can display on the R Windows device. I have experimented with readBin, using a simple

Jonathan, Try making a list instead of an array. See ?list. Also, did you look into random forests? I'm not sure what you want to do, but there might be methods there to do some of the work for you. Sean On 3/19/04 1:12 PM, "Jonathan Williams" <jonathan.williams at pharmacology.oxford.ac.uk> wrote: > I would like to collect the trees grown by rpart fits in an array,

Dear R helpers, I wish to use the "sum" operator for each row of a data frame. However, it appears that the operator acts on the entire data frame, over all columns. What is the best way to obtain row- wise operation? The following code shows my attempts so far, and their problems:- test1=array(rbinom(120,1,0.5),c(20,3)) test1[,3]=NA sum(test1[,1:2]) test1[,3][sum(test1[,1:2])>=2]=1

Oh dear - I joined the R help mailing list last week, in order to ask a specific question. I did not realise that I would start to receive all e-mails to and from the mailing list. Is there a way of letting me receive only the answers to my own questions? If not, then can you remove me from the mailing list? Thanks, Jonathan Williams Jonathan Williams OPTIMA Radcliffe Infirmary Woodstock Road

I am trying to analyse recurrent failure times using survfitr from the survrec package. To do this, I need to "Create a survival recurrent object" using Survr. But, when I do this, I get an error "Error in Survr(r1d[, 1], r1d[, 5], r1d[, 6]) : data doesn't match". Here, r1d[,1] is the identifier for each case, r1d[,5] is the time of recurrence, r1d[,6] is the status

Dear R helpers, I would like to ask why polr occasionally generates results that look very odd. I have been trying to compare the power of proportional odds logistic regression with the Wilcoxon test. I generated random samples, applied both tests and extracted and compared the p-values, thus:- library(MASS) c1=rep(NA,100); c2=c1 for (run in 1:100) { dat=c(rbinom(20,12,0.65),rbinom(20,12,0.35))

I am having great difficulty plotting what should be a simple graph. I have measured 1 'y' and 5 'x' variables in each of two groups. Linear regression shows significant differences in the slopes of the regression for each 'x' variable between the two groups. All that I want to do is to plot one graph that shows the scatterplot for the three groups (each group represented

Dear R-helpers, I have found a slightly annoying problem when trying to plot lines on graphs. I first created my data using tapply, thus:- y1=as.vector(fit1$coef$random$id) x1=tapply(o1,id,median,na.rm=T) x2=tapply(o2,id,median,na.rm=T) #then I plot the data, thus:- plot(x1[x2==0],y[x2==0]) #if I now try to fit the linear regression, R 'hangs up'

Dear R helpers, I have a curious problem, which is that a program I have written in R crashes R, unpredictably. When I say that the program crashes R, I mean that it causes R to terminate, completely. But, the operating system (Windows) continues OK. The program loops around a randomForest regression. I am trying to use randomForest to predict the diagnosis for a set of patients with dementia. I

Jonathan, Is there any possibility for you to send me the data, and/or the code? I and others have seen similar problems before, but not reproducible on the current version, at least on the NT and Linux boxes that I have access to. As Thomas said, it's difficult to nail these kinds of problems. Having reproducible data and code, at least, can help. (It's no help that I'm no expert

I have a time series of data from an electroencephalogram (EEG). I wish to filter the data to get rid of 50Hz mains 'hum'. I have 'designed' a combination bandpass and notch filter using a web- site. The site returns the filter in "ANSI C" source code. It is:- /* Digital filter designed by mkfilter/mkshape/gencode A.J. Fisher Command line:

Is there a good way in R to impute values which exist, but are less than the detection level for an assay? Thanks, Jonathan Williams OPTIMA Radcliffe Infirmary Woodstock Road OXFORD OX2 6HE Tel +1865 (2)24356

Dear R-helpers, I want to try to extract residuals from a multi-level linear mixed effects model, to correlate with another variable. I need to know which residuals relate to which experimental units in the lme. I can show the labels that relate to the experimental units via the command ranef(fit0)$resid which gives: 604/1/0 -1.276971e-05 604/1/1 -1.078644e-03 606/1/0 -7.391706e-03 606/1/1

Hi, I've just started setting Samba up so I'm at quite an elementary stage! I'm using Samba 2.2.8a on a Solaris 7 server. I can connect to Samba ok when using localhost from the console. However when I try and use DOS from a Win95 test machine I get a message saying the computer name was not recognised. This points to the nameserver not running (I'm using nmbd provided with

Hi, This may seem a fairly obvious question but I need to check it out. It's also fairly urgent so I apologise that I haven't made a good check of the FAQ's or mailing archives. We have a Solaris box with Samba installed. We are on a campus network where boxes that are infected are blocked from the network as a security measure. We have had our server blocked as it is probing port

Dear R-helpers, I am having difficulty making R plot only integer labels on the x-axis of a simple graph. I want to plot the median values of a score on each of three occasions. Non-integer occasions are impossible. But, R keeps labelling the x-axis with half-occasions, despite my attempts to stop this using the "xaxs" and "xaxp" parameters of 'plot'. p1=c(1,2,3);

Greetings, I use S+, Stata, SAS and R depending on the weather... The script file editors in S+, SAS and Stata all allow me to submit a portion of a developing script file to the running process. In R I have to use an external editor and either source the entire file or do lots of copy-and-pasting. Are there any editors out there which interface to R more closely and let me submit a section