similar to: Fitting a half-ellipse curve

Hi R mailing list, probably a very basic problem here, I try to do the following: > Q<-c(1,2,3) > P<-c(4,5,6) > A<- data.frame(Q,P) > A Q P 1 1 4 2 2 5 3 3 6 this is my simplified data.frame (matrix) now I try to create following loop for subtraction of element within the data.frame: > for(i in length(A[,"P"]-1){ delta[i]<-

Hi list, I am writing several functions and running out variable names. I am using words such as "t", "c", "matrix" to keep the notation same as formulas I am using. For example I have, unnormalized <- function(t, x, y){ val <- rnorm(t, mean=x, var=y) return(val) } metropolis <- function(t, c, x, y){ den1 <- unnormalized(t, mean=x, sd=y)

Greetings, I am struggling a bit with a non-linear regression. The problem is described below with the known values r and D inidcated. I tried to alter the start values but get always following error message: Error in nlsModel(formula, mf, start, wts): singular gradient matrix at initial parameter estimates Calls: nls -> switch -> nlsModel I might be missing something with regard to the

Hi We have been trying back-up a glusterfs (v3.1.4) area using the Tivoli TSM software to an off-site area. The back-up keeps failing with the following typical error messages 06/14/2011 22:22:58 ANS1587W I/O error reading file attributes for: /gdata/projects/philex/OAG/2011/May16/mdor3km10/coast_den2.in. errno = 22, Invalid argument 06/14/2011 22:22:59 ANS4007E Error processing

Hi R-mailing list I would have the following set-up below with a simplified data-frame. Through a loop which includes certain criteria for the densities I would like to plot the different density-distributions in the same plot. Of course I hope I don't do any mistakes with all the indexes of the dataframe. All I would like to have is the different densities in the same plot with a general

Hello, Does somebody knows if there exists a function which solves a set of equation, say f(vars), for the variables vars (similar to Solve in mathematica). The functions I am considering are of the form f(t) ~ A*exp(B*t), where A and B are matrices. Thanks Thomas

Hi, I was wondering if function eigen() does something different from the function call eigen() in SAS. I'm in the process of translating a SAS code into a R code and the values of the eigenvectors and eigenvalues of a square matrix came out to be different from the values in SAS. I would also appreciate it if someone can explain the difference in simple terms. I'm pretty new to both

Hello, I have a short question about the prcomp function. First I cite the associated help page (help(prcomp)): "Value: ... SDEV the standard deviations of the principal components (i.e., the square roots of the eigenvalues of the covariance/correlation matrix, though the calculation is actually done with the singular values of the data matrix). ROTATION the matrix of variable loadings

Hi, I wanted to plot the histogram of a vector and then, plot the density function of subsets of the vector on the histogram. So I use truehist in MASS package and lines(density) as follows: length(b) = 1000 truehist(b) lines(density(b[1:100])) however the density plot of the first 100 points exceeds the max of y axis (see attached). how is it possible to make a graphics so that the density plot

Hi all, Is there a function to check if a particular value is contained in a vector? I've looked at grep in the hope that I could use a Perl-like syntax, but obviously it's different... I'd like to do something like: y <- c("a","b","c") if("a" in y) { # "a" is not in y } Also, is there a way to

Hi We have a Replica 2 + Arbiter Gluster setup with 3 nodes Server1, Server2 and Server3 where Server3 is the Arbiter node. There are several Gluster volumes ontop of that setup. They all look a bit like this: gluster volume info gv-tier1-vm-01 [...] Number of Bricks: 1 x (2 + 1) = 3 [...] Bricks: Brick1: Server1:/var/data/lv-vm-01 Brick2: Server2:/var/data/lv-vm-01 Brick3:

Hi all, Given a number of points (x,y) in a plane, I'd like to plot a map of polygons, so that 1) each polygon contains exactly one point 2) the polygon defines the area for which this specific point is closer than any other point. It's a bit like a map of areas "influenced" by that point, and it's obviously a matter of intersecting the perpendicular bisectors

Hi all, I am trying to produce some panels with dots in an X/Y plane where the diameter of the dots indicates a Z value (like e.g. earthquake maps where dot sizes indicate magnitudes and X/Y the location). This works fine with xyplot, e.g.: xyplot(1:3~1:3,cex=1:3,pch=16) However, when I do this with a panel variable, e.g.: x<-rep(1:3,5) y <- rep(1:3,5) sz <- rep(1:5,each=3) grp

I originally sent this to samba-technical which as a typical first stpe for me was probably wrong.... ;-) Anyone here have any ideas? -----Original Message----- From: Petty, Robert [mailto:rpetty@denvernewspaperagency.com] Sent: Tuesday, September 23, 2003 10:07 AM To: samba-technical@lists.samba.org Subject: Samba 2.2.8a / Winbind and Domains I have searched the archived through google and

What's the logic behind the following, and where can I find any documentation about it? In particular, why are 2:9 - as characters - not regarded as being smaller than 10? # R-Code: a <- as.character(1:12) a < 10 # [1] TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE Thanks in advance! Niklaus

Dear all, I am not sure if this mail is for R-help or should be sent to R-devel instead, and therefore post to both. While using nlrob from package 'robustbase', I ran into the following problem: For psi-functions that can become zero (e.g. psi.bisquare), weights in the internal call to nls can become zero. Example: d <- data.frame(x=1:5,y=c(2,3,5,10,9)) d.nlrob <-

Hi all, I ran into a problem in some of my code that could be traced back to 'mean' sometimes returning NA and sometimes NaN, depending on the value of na.rm: > mean(c()) [1] NA > mean(c(NA),na.rm=T) [1] NaN However, I don't understand the reasoning behind this and would appreciate and explanation. I understand that the mean of an empty vector is not definied, but I

Hi all, I wonder how to correctly write the following expression (it's the axis label in a plot command): ylab=expression(y' == y - bar(y) ) Somehow the single quote in y' is causing the problems, I guess because it is interpreted as a quote... Does it have to be escaped? But how? Thanks for your help Pascal

Hi, well after some ever further investigation of some bugs, I ended up cleaning up the code, again. I also fixed some really heavy memory leaks in csvToList and made it in general more stable. Regards, Patrick "Marex" Niklaus -------------- next part -------------- A non-text attachment was scrubbed... Name: ini.c.patch Type: text/x-patch Size: 8275 bytes Desc: not available Url :

GENERAL REFERENCE ON NONLINEAR OPTIMIZATION? What are your favorite references on nonlinear optimization? I like Bates and Watts (1988) Nonlinear Regression Analysis and Its Applications (Wiley), especially for its key insights regarding parameter effects vs. intrinsic curvature. Before I spent time and money on several of the refences cited on the help pages for "optim",