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Levi Larkey schrieb: > Hi, > > I'm somewhat new to R and I'm trying to figure out the difference > between the operators <- and =. <- is an assignement operator = is primarily used for named arguments Some thoughts about the use of = as...

Laurent Houdusse schrieb: > Hi all! > > How to retrieve the levels number of a factor object? > See this code: > groups<-gl(4,10) > I want to retrieve the number of levels (4) of my object "groups" > I tried groups.levels but...

Hello Frank, does the following example, what you want? Thomas P. ## some test data x <- data.frame(matrix(rnorm(72*10, mean=50, sd=20), ncol=10)) me <- colMeans(x) sd <- apply(x, 2, sd) coff <- me + 2*sd # see...

Hi, your idea for a smoothed impulse function seems quite close to a good solution, what about: x <- seq(-20, 20, 1e-3) steep <- 20 plot(x, (tanh(steep * (x %% 10 - 8)) - tanh(steep * (x %% 10 - 2)))/2 + 1, type...

On 09.01.2013 16:28, Felix Sch?nbrodt wrote: > Thanks! Works like a charm. > Felix Thanks to Karline Soetaert who implemented this mechanism and also to Woodrow Setzer. Instead of a data frame it is also possible (and even...

Svetlana Eden wrote: > Hi, everybody. > This was an interesting discussion last time and it helped me a lot. > > Could you please have a look at some feature and tell me > why it was designed this way What you see in...

Raymond Balise wrote: > What is the name of the function to give me the mode (central tendancy) of a > numeric variable that can be negative? Similar questions appear occasionally on this list. Please see the following help page for possible...

Thomas Lumley wrote: > On Thu, 29 Apr 2004, Thomas Petzoldt wrote: > >>If you want to make a subsample, you can select cases (rows) using >>sub(), see ?sub for details, e.g. somethink like: >> > > > I think you mean subset(). sub() is...

Ann Devitt schrieb: > Hello, > is there any documentation on doing principal components analysis with R > besides the R manual itself which is not very informative yes, see the reference cited on the princomp() - help page: Venables, W. N. and B...

Hi, did you test for simultanaeous identifiability of your parameters? If not, then this may be an idea, and you may also try to fix one or several parameters and try to fit the others. In addition, you may consider...

m p wrote: > Hello, > I am looking for a R routine to fit a function/surface > to my data 3d data. I'd like to use the function in a > model so something like splines is not applicable. > The data...

Hello, the Jacobian is optional, so you can safely omit it. However, specifying the Jacobian (or at least its structure) can speed up the integration of the odepack solvers, e.g. for 1D, 2D and 3D systems. The Runge-Kutta...

Hi, one additional remark: I assume that the setting of "maxsteps = 10" was intentional to force the warnings in the exymple. It is the maximum of the internal iteration counter (e.g. adams or bdf). The default value is 5000...

Marc Schwartz wrote: > In general, if you want to leave the existing device open and have a new > device open for a new plot, you simply call the device name that you > want to open (ie. under Linux you would...

Hello, I am looking for an interpolation method similar to the one-dimensional AKIMA interpolation as in Akima (1970). Is there already such an algorithm in R which I may have overlooked? Thank you in advance Thomas P. H. Akima...

Erin Hodgess wrote: > Hi Thomas! > > Try something like this: > > fx <- function(y) print(x*y) > > f <- function(fun,x) { > assign("x",x,env=.GlobalEnv) > fxx <- function() { > do.call(fun,list(y=3)) > } > fxx() > } > > f("fx",13) > > [1] 39 > > > Hope this...

Another hint, try: out <- ode(state6, 0:100, BIOGEO6, parms=parameters6) init <- out[64, 2:29] outx <- ode(init, seq(63, 63.4, 0.01), BIOGEO6, parms=parameters6) tail(outx[,2:29]) ... that runs the model during the critical time...

Michael Kirschbaum schrieb: > Hi Everyone. > > I have a simple problem but don't know, how to get along. > > how can I convert the vector > > a<-c("0,01","1,00") > in a vector > b<-c(0.01,1.00) > > Thank...

Thanks for clarification. The transformation of a second order derivative is briefly shown here: https://journal.r-project.org/archive/2010-2/RJournal_2010-2_Soetaert~et~al.pdf#3 and some more may be found in the book of...

Hi Thomas, your question was not very specific and did not contain a "minimal reproducible example". Anyway, you may find some information about Kalman filtering in R in the book of Shumway and Stoffer: "Time Series Analysis and Its Applications...