similar to: System.time

There is a R function to calculate weighted mean : weighted.mean() under stats package. Is there any direct R function for calculating weighted variance as well? [[alternative HTML version deleted]]

Hi All, would appreciate an answer on this if you have a moment; Is there a function (before I try and write it !) that allows the input of a covariance or correlation matrix to calculate PCA, rather than the actual data as in princomp() Regards Glenn [[alternative HTML version deleted]]

Lately I'm getting this error quite a bit: Error in La.svd(x, nu, nv) : error code 1 from Lapack routine 'dgesdd' I'm running R 2.5.0 on a 64 bit Intel machine running Fedora (8 I think). Maybe the 64 bit platform is more fragile about declaring convergence. I'm seeing way more of these errors than I ever have before. From R-Help I see that this issue comes up from time to

Hi, Is there a way to convert a matrix into a vector representing all permutations of values and column/row headings with native R functions? I did this with 2 nested for loops and it took about 25 minutes to run on a ~700x700 matrix. I'm assuming there must be a smarter way to do this with R's vector commands, but being new to R, I'm having trouble making it work. Thanks,

Dear List, A student in the Department where I work would like to produce a graphic similar to this one: http://image.guardian.co.uk/sys-files/Guardian/documents/2009/09/16/Public_spending_160909.pdf Does anyone know if the figure in the pdf can be generated in a specific software application for example? Any suggestions would be most gratefully received by the student concerned. Many thanks,

hello R-masters. i have an R-issue here that i don't know if you'd wish to help me? about it: briefly i'd like to generate many (say hundred) realizations of a random walk, execute a few operations on each of them (mean time of return), and graph each realization on the same plot. IN OTHER WORDS I'D LIKE TO IMPOSE A LOOPING CYCLE TO THE COMMAND NOT THE ARGUMENT OF THE COMMAND.

Greetings, I have the following simple function but what worries me is that it takes about 5 or more minutes to execute. My machine runs on windows with 1.8GHz and 256 Ram. > Re=NULL > for(i in 1:100000){ + x=rnorm(20) + Re[i]=(x-2*10)/20 + Re + } I would appreciate any help on how to make it faster. Usman ___________________________________________________________ now.

Hello there, I'm trying to plot vectors with p<0.1 in a NMDS ordination plot using p.max. Below the scripts I'm using. I guess I'm missing something! could you please give me a hand? species<-metaMDS(species_matrix)ef<-envfit(species,environmentaldata_file,permu=999,na.rm=TRUE)efplot(species, dis="sites")plot(ef,p.max=0.1) Error in plot.envfit(ef, p.max = 0.1) :

Sorry to disturb you, but can you help me to solve one little problem? I want to draw a graphic after another with R but I cannot find the first one after that. Do you know the command to hold the graphic with R? I remember with Matlab you may use "hold on". Thanks. -- Baohua Yang Email:yangbaohua@gmail.com [[alternative HTML version deleted]]

Hi I am trying to run Factor Analysis using R...I am using the syntax factanal(m1, factors=3) but it's giving me an message Error in cov.wt(z) : 'x' must contain finite values only ...I am using a data set which is having only numeric variables and have some NA's also in it..What should I do next..Someone please help me out with the syntax..Thanks in advance Cheers Arup --

Dear List, I need to add a subscript and a superscript to some of the ions in the labels on some plots. I have got to here but now I'm stuck: plot(1:10, xlab = expression(paste("nm SO"[4], " ", mu, "eq cm"^{-2}, " yr"^{-1}))) Which gives almost what I require. No matter what I tried, however, I could not get bot a sub script *and* a superscript

Dear R, the condition: identical(length(x),1) returns FALSE but print(length(x)) returns 1 and: is.vector(x) is TRUE. is.integer(length(x)) is TRUE length(x) ==1 is TRUE I am puzzled. Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk

Hi, there, I cannot get accurate value for calculation. for example: ld<-sqrt(1*0.05*0.95*0.05*0.95) 0.05*0.95-ld=-6.938894e-18 0.05*0.95-ld==0 is False. I met this problem in my program, how can I handle it. Thanks. xj.

Dear List, I am having trouble with some R code I have written to perform Redundancy Analysis (RDA) on a matrix of species abundance data (Y) and a matrix of environmental data (X). RDA is a constrained form of PCA and can be thought of as a PCA of the fitted values of a regression of each variable in Y on all variables in X. For info, the first use of RDA is in: Rao, C.R, 1964. The use and

Hi list I loaded the content of a file dureetasks.txt to variable a. This file contains an interger per line. when I print a vector, it displays correctly. however, when I try to print the histogram, I get this error message > a=read.table("dureetasks.txt") > hist(a) Error in hist.default(a) : 'x' must be numeric Can you help please? regards -- PhD candidate in

Hi I'm having a problem with model.frame, encapsulated in this example: y1 <- matrix(c(3,1,0,1,0,1,1,0,0,0,1,0,0,0,1,1,0,1,1,1), nrow = 5, byrow = TRUE) y1 <- as.data.frame(y1) rownames(y1) <- paste("site", 1:5, sep = "") colnames(y1) <- paste("spp", 1:4, sep = "") y1 model.frame(~ y1) Error in model.frame(formula, rownames,

Dear all, How can I run a constrained correspondence analysis with the following data: 15 animals were measured repeatedly month-wise (over to 2 years) according to ther diet composition (8 food categories). our data.frame looks like this: food 1 2 ... 8 sex season year animal freq 12 8 ... 1 0 summer 2011 1 freq 0 7 ... 0 1 winter 2011 1 ... freq 0 7 ... 0 1 spring 2011 15 We

Dear List, I often have to merge two or more data frames containing unique row names but with some columns (names) common to the two data frames and some columns not common. This toy example will explain the kind of setup I am talking about: mat1 <- as.data.frame(matrix(rnorm(20), nrow = 5)) mat2 <- as.data.frame(matrix(rnorm(20), nrow = 4)) rownames(mat1) <- paste("site",

Dear list, given this formula: > fmla <- formula(y1 ~ spp1 + spp2 + spp3 + spp5) > fmla[[3]] spp1 + spp2 + spp3 + spp5 is this the intended behaviour of as.character: > as.character(fmla[[3]]) [1] "+" "spp1 + spp2 + spp3" "spp5" ? Where does the extra "+" come from? > as.character(fmla) [1] "~"

Dear all I try to format labels on axis as standard ones does not look well, but I am not able to make axis.POSIXct to work. here is an example x<-seq(as.Date("2008-1-1"), as.Date("2009-9-6"), by="2 months") y<-rnorm(11) plot(x,y) #not very sophisticated axis plot(x,y, axes=F) axis(2) axis.POSIXct(1, at=x, format="%m/%Y") # no axis The same is on