similar to: Calling Windows DLL using .C; function name not known but in exports.

I cannot understand why a function appears to be available to R (is.loaded('planckwR') returns TRUE) but the call with .C results in an error message: C symbol name 'planckwR' not in DLL for package <path to DLL file here> This is what I do: Loading a homebrewed DLL, compiled with MS VS97. The functions are all void, the C calling sequence is used and all arguments

Hi I'm trying to write a generic script for processing some data which finishes off with some plots. Given Im never sure how many columns will be in my dataframe I wanted to using the following plot(spectra.wavelength, cormat, type = "l", ylim=c(-1,1), xlab="Wavelength (nm)", ylab="Correlation") however even if I specify as type="l" it appears plot

Dear R users, I am a newbie. Just switched from MATLAB. So thanks a lot for your patience. I have 50000 spectra collected in field. Each spectra has two columns : Wavelength (56) and the actual measurement. Each measurement came in a different .txt file on disk (50000 files in total). I wrote a script that reads every spectra in a for loop and constructs two variables : Wavelength (56) and

Hi, I have some difficulty in figuring out whether I am doing correct or not. A brief introduction about the work: It is a light/dark choice test conducted in insect larvae.  The response is binary (0- present in dark area, 1-present in light area) and the experiment is run for 15 min, so there are 15 repeated measurements per individual larva at 1 min intervals.  The factors which affect

Dear all, I wrote a wrapper to a FORTRAN program using R. The main program uses a text file (~200 lines) as an input describing the simulation to be run. I typically generate the file once with the right parameters using a combination of file(), paste(), cat(). This is fine, and it works well, however I then need to update only a few values in the file many times (~200 times,

I have a spectrophotometric dataset with repeated measures of a value at 200 wavelengths for each of 150 individuals. I would like to use the repeated samples to at each wavelength to look at measurement/observer error, compared to difference between individuals error I have looked at doing this with icc{irr} or using an anova approach, but I am unclear how to acheive this given that there

Hi, I am currently analysis Raman spectroscopic data with the hyperSpec package. I consulted the documentation on this package and I found an example work-flow dedicated to Raman spectroscopy (see the address : http://hyperspec.r-forge.r-project.org/chondro.pdf) I am currently trying to remove outliers thanks to PCA just as they did in the documentation, but I get a message error I can't

plot.ts has an argument yax.flip, plot.zoo does not. Is there a way to make the yaxis flip in plot.zoo? I tried using a custom panel function: panel.yaxis<-function(...) { npnl<-parent.frame$panel.number if (npnl %% 2 == 0) { axis(side=3) } else { axis(side=2) } } This leads to a blank window. I am stuck with the intricacies of the plotting and axis

Reading a flat text file 138 Mbyte large into R with a combination of scan (to get the header) and read.table. After conversion of text time stamps to POSIXct and conversion of integer codes to factors I convert everything into one data frame and release the old structures containing the data by using rm(). Strangely, the rm() does not appear to reduce the used memory. I checked using

Hi, I'm new to R and looking for a way to use a variable to reference to an object. I'm plotting several graphs on top of each other and want to do this by a for loop. The field I want to graph have names like a1,a2,a3, ... I can't figure out how to get this working: It should look like this: lines(spectral$Wavelength,paste("spectral$a",j,sep=""),col=j) but

Dear R users, I have spectral data (say, wavelength vs. extinction coefficient) for which I??d like to calculate an integral (i.e. the area underneath the curve). Suppose the (artificial) dataset is lambda E 1 2 2 4 3 5 4 8 5 1 6 5 7 4 8 9 9 8 10 2 How can I calculate an integral for these values using R? Many thanks for any help! Regards Christoph

I have to decode raw vectors read from a connection like this: +++++++++++++++++++ fl<-file.choose() fb<-file.info(fl)$size fc<-file(fl) open(fc,open='rb') seek(fc,where=offset) dat<-readBin(fc,'raw',n=(fb-offset),size=1,signed=FALSE) close(fc) ++++++++++++++++++ The decoding performs a combination of a simple bitwise operator and a simple arithmatic operator on

Is there a way to make any of the write functions (.table or .csv) append to the same file? I get this warning message and do not know how to enable the appending. Warning messages: 1: In write.csv(names(Lbys)[c], fo, append = TRUE) : attempt to set 'append' ignored 2: In write.csv(Lbys[[c]], fo, append = TRUE) : attempt to set 'append' ignored Regards, Alex van der Spek

panel.lmline returns intercept and slope of y ~ x subsetted to the combination of conditioning factors given to xyplot in lattice. for instance: xyplot(Xvalues ~ log(Qvalues)|Tfac, data = df7, panel = panel.lmline) I am looking to find the equivalent formulation for lm() proper. If I do this: lmcal <- lm(Xvalues ~ log(Qvalues):Tfac, data = df7) Only one value of the intercept is returned.

Dear lme and lmer -ers, I have some problems using "home-made" contrast matrix in lme and lmer. I did an experiment to investigate the relationship between the response of an animal and some factors, namely the light wavelength (WA), the light intensity to which this animal was exposed and the sex of the animal tested. - The response can be a variable LA (normal distribution) or

I cannot figure out how to tune the minor tic marks on the date axis of a zoo plot. I read hundreds of CSV files from a zip archive transparently. The time/date strings I convert to POSIXct format, order them and then make a zoo object as there may be cases which have unequal time stamping. As follows: ###################### #Transform timestamps and reorder them dat <- transform(dat,

Hello everyone, I have an overlay plot it's nice but you can't see all the data. I would like to know if there is a way to get a plot that gives a side by side plot so that each plot would be next to each other. The two plots have the same data are of different species. At the moment this is the code I'm using: exp<-cbind(abs(round(rnorm(10),2)*10), seq(100, 200, by=10))

Hi there, I try to plot visible light spectrum (380nm~780nm) with color corresponding to the specific wavelength. However, I don't find a function that could do this. Another question, it's possible to plot a color space chromaticity diagram like this: http://upload.wikimedia.org/wikipedia/commons/thumb/0/02/CIExy1931.svg/300px-CIExy1931.svg.png Thanks in advance! Jinsong

I use by() to generate a summary statistics like so: Lbys <- by(dat[Nidx], dat$LipTest, summary) where Nidx is an index vector with names picking out the columns in the data frame dat. This returns a list of character arrays (see below for str() output) where the columns are named correctly but the rownames are empty strings and the values are strings prepended with the summary

Hi All, Have spent the last couple of days learning R and shell scripting to do batch plotting jobs. I have had success getting R to complete a filled contour plot and output to a file (.jpg or .tiff etc). However, when I try to do the same thing with the simple plot command the script seems to execute correctly yet there is no output. Below is my R code: file <-