search for: wavelength

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 as points (right hand plot). If I specify a range such as plot(650:700, cormat, type = "l", ylim=c(-1,1), xlab=&q...

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 Reflectance (56x50000). I would like to plot Reflectance vs Wavelength i.e....

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 another variable PE (normal distribution). Each analysed separately. - WA has 6 different levels: 400, 430, 470, 540, 570, 620 nm. - the light i...

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...

Hello Im trying to install an old version of Asterisk. But it isnt working: when I run "make install": gcc -o gentone gentone.c -lm ./gentone busy 480 620 Wavelength 1 (in samples): 16.66667 Minimum samples (1): 50 (3.000000.3 wavelengths) Wavelength 1 (in samples): 12.90323 Minimum samples (1): 400 (31.000000.3 wavelengths) Need 400 samples Wrote busy.h ./gentone ringtone 440 480 Wavelength 1 (in samples): 18.18182 Minimum samples (1): 200 (11.000000.3 w...

...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 this study are Strain (2 levels-G and S),  wavelength of light (4 levels-blue, green, UV, red), and starting response at 0 min (two levels- animal present in dark-D or light-L).  This is how I think it is nested.  Strain nested inside Wavelength, Subject (individual) nested within strain, Starting response within subject, and time within Starting r...

...[CC] iax2-parser.c -> iax2-parser.o [CC] iax2-provision.c -> iax2-provision.o [LD] chan_iax2.o iax2-parser.o iax2-provision.o -> chan_iax2.so [CC] chan_local.c -> chan_local.o [LD] chan_local.o -> chan_local.so [LD] gentone.c -> gentone ./gentone busy 480 620 Wavelength 1 (in samples): 16.66667 Minimum samples (1): 50 (3.000000.3 wavelengths) Wavelength 1 (in samples): 12.90323 Minimum samples (1): 400 (31.000000.3 wavelengths) Need 400 samples Wrote busy.h ./gentone ringtone 440 480 Wavelength 1 (in samples): 18.18182 Minimum samples (1): 200 (11.000000.3 w...

...ith dumpbin I can see that the function I need is exported under the name 'planckwR'. Loading the DLL with dyn.load(dllpath). Works fine. getLoadedDLLs() shows info on the 'Planck.dll' that I made. So far so good. Made a function i R like this: Planckw<-function(Temp) { wavelength<-0.0 .C('planckwR',as.double(Temp),as.double(wavelength)) return(wavelength) } Calling this function, R complains the function 'planckwR' is not in the DLL. This baffled me as I can see it in the exports table using dumpbin. I use Visual C++ 97 compiler. Old but wor...

...w values in the file many times (~200 times, typically). I've used Ruby for this task in the past, and I wonder whether there is a simple and efficient way to achieve this in R. Here's a minimal example, myFile <- "test.txt" writeHeader <- function (out=myFile, N=5, wavelength=0.1) { output <- file(paste(out), "w") headerString <- c("Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip e...

...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 the "paste()" does not seem to work in this context. Any help? Kind regards, Kris -- ------------------------------------------------------------------------ http://perswww.kuleuven.ac.be/~u0027178/VCard/mycard.php?name=...

My tuneR sawtooth wave function generator is broken. When I use the sine function, I get exactly what I expect: a sine wave whose frequency is defined by the freq parameter. In particular, higher frequencies have shorter wavelengths (more cycles per second means shorter waves). When I create a sawtooth wave, the opposite seems to occur: higher frequencies result in longer waves. But that?s not all: as frequencies increase, it appears that wavelengths increase to infinite length, then get shorter again as the wave reverses,...

...dro.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 explain. Here is my code : "#import the data : T=read.table('bladder bis concatenation colonne.txt',header=TRUE) spec=new("hyperSpec",wavelength=T[,1],spc=t(T[,-1]),data=data.frame(sample=colnames(T[,-1])),label=list(.wavelength="Raman shift (cm-1)",spc="Intensity (a.u.)")) #baseline correction of the spectra spec=spec[,,500~1800] bl=spc.fit.poly.below(spec) spec=spec-bl #normalization of the spectra spec=sweep(spec,1,...

...the code to process my data. My current data structure consists of a .csv file read into R containing 15 columns (a charcoal dilution series going from 100% to 0%) and 1050 rows of absorbance data from 400 nm to 2500 nm at 2 nm interval. I think I need to transpose the data such that the specific wavelengths become my columns and dilutions are defined in rows, but after that point I am lost. Should I (and how do I) make my absorbance data into individual matrices that read into a data frame with only two columns (dilution vs spectra or something of the sort that both the yarn and gasoline data use)? T...

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...

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

...y beneath the center of the microscope's lens (see the picture below or AIP page: http://www.aip.org/history/heisenberg/p08b.htm). The circular lens forms a cone of angle 2A from the electron. The electron is then illuminated from the left by gamma rays--high energy light which has the shortest wavelength. These yield the highest resolution, for according to a principle of wave optics, the microscope can resolve (that is, "see" or distinguish) objects to a size of dx, which is related to and to the wavelength L of the gamma ray, by the expression: dx = L/(2sinA)...

...y beneath the center of the microscope's lens (see the picture below or AIP page: http://www.aip.org/history/heisenberg/p08b.htm). The circular lens forms a cone of angle 2A from the electron. The electron is then illuminated from the left by gamma rays--high energy light which has the shortest wavelength. These yield the highest resolution, for according to a principle of wave optics, the microscope can resolve (that is, "see" or distinguish) objects to a size of dx, which is related to and to the wavelength L of the gamma ray, by the expression: dx = L/(2sinA)...

...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)) ref<-cbind(abs(round(rnorm(10),2)*10), seq(100, 200, by=10)) plot(ref, ylab="Intensity", xlab="wavelength", type="h") points(exp, type="h", col="red") This is working in a script and I would like to have a single pdf/png file for the user with this plot, rather than asking the user to manually compare them. Any ideas on how I would do this? Thanks Paul

...T, Michael Tiemann <mdtiemann at gmail.com> wrote: >My tuneR sawtooth wave function generator is broken. > >When I use the sine function, I get exactly what I expect: a sine wave >whose frequency is defined by the freq parameter. In particular, >higher frequencies have shorter wavelengths (more cycles per second >means shorter waves). When I create a sawtooth wave, the opposite >seems to occur: higher frequencies result in longer waves. But that?s >not all: as frequencies increase, it appears that wavelengths increase >to infinite length, then get shorter again as the...

...email, but i just showed part of my data so you could better understand my problem): ______________ X1242 X1242.5 X1243 X1243.5 X1244 X1244.5 X1245 X1245.5 X1246 X1246.5 X1247 X1247.5 X1248 X1248.5 X1249 => names of each data set ( corresponds to wavelengths, ranges from 400 to 2500 with 0.5 steps => a lot of points!) 18.14 0.9860316 0.9860272 0.9860203 0.9860121 0.9860044 0.9859994 0.9859971 0.9859976 0.9859999 0.9860035 0.9860069 0.9860103 0.9860128 0.9860151 0.9860178 15.8 0.9857134 0.9857106 0.9857063 0.9857011 0.9856958 0.9856917 0.9856887 0....