search for: rrsilva

I am trying to use the function gl (generate levels), and would like to make levels with different number of replications. Does anyone know how to generate different number of replications in each level? Something like: [1] Site1 Site1 Site1 Site1 Site1 Site1 Site1 [8] Site2 Site2 Site2 Site2 Site2 Thanks in advance -- Rog?rio R. Silva MZUSP http://www.mz.usp.br Linux/Debian User # 354364

Dear all As part of an ongoing study on the ecomorphology of ant communities, I have obtained a matrix with 156 row (species) and 20 columns (several measurements of body shape) for 4 localities. For each community, I calculated a matrix of Euclidean distances between all pairs of species. From this matrix, I extracted two measures of community structure: i) I identified the distance from a

Dear all, I am trying to extract rows from a data.frame based on the rowSums != 0. I want to preserve rownames in the first column in the subset. Does anyone know how to extract all species that don't have rowSums equal to zero? Here it is: # dataset x <- data.frame( species=c("sp.1","sp.2","sp.3","sp.4"), site1=c(2,3,0,0), site2=c(0,0,0,0),

Hello, I'm a new user of R, and unsure of why I'm getting an error reading external files on my Mac OS 8.6 machine. I've read through posts that would seem related (and 'R Import/Export' and 'Introduction to R') but to no avail. If anyone has any suggestions, I'd be very grateful. Here's the problem: When I enter the command: > guilds <-

Hi, In my data set I have created a matrix of distances. How can I get a list of minimum value in each row? thanks a lot, Rog?rio

Dears R users, Is there a way to add a column of results to an exported data.frame (exported with write) ? Thanks Rog?rio

Dear all, I'm having difficulty getting the procedure for discriminant analysis. How can I specify the forward or backward stepwise analyses of variables into the model? I'm using lda in MASS and discrimin (ade4). I run R version 1.9.1. Thanks, Rog??rio

Dear List: I have the following simple program: x<- sample(site) VarGuilda1<- var(tapply(x,site,func1)) VarGuilda2<- var(tapply(x,site,func2)) VarGuilda3<- var(tapply(x,site,func3)) VarGuilda4<- var(tapply(x,site,func4)) VarGuilda5<- var(tapply(x,site,func5)) VarGuilda6<- var(tapply(x,site,func6)) VarGuilda7<- var(tapply(x,site,func7)) VarGuilda8<-

Dear List, I've around 1000 *.txt files, I've generate with other software. I've now done the following code (below). My question is how can I automate this (with do.call () ?), so it could be done for all the *.txt files. Thanks in advance, Rog??rio names<- list.files() file <- "BLU_Var_%04d.txt" for(i in 1:1000){