[R] How to make sure R's g++ compiler uses certain C++ flags when making a package

I am trying to use some code from opencv in an r package, using Rcpp to build the package. When I compile the c code on my machine, it works fine. However, when I try to include it in my package, it gives me a bunch of error messages like: "error: opencv2/core/operations.hpp: No such file or di

Re: [R] Using summaryBy with weighted data

t; uses primary principles of SQL. > > data.table has a vignette and FAQ, along with an independent help list - for > details, see its page on R-forge: > http://r-forge.r-project.org/projects/datatable/ > For plyr's documentation, see > http://had.co.nz/plyr/ > A link to it

Re: [R] Using summaryBy with weighted data

msenw) data.frame( group = names(c(xy)), do.call(rbind, xy) ) ## can be extended to other data using: xy <- by(data.frame(response = mydata$response, weights = mydata$weights), mydata$group, msenw) Solomon Messing www.stanford.edu/~messing On Jan 16, 2011, at 11:16 PM, Joshua Wiley wrote: >

[R] Using summaryBy with weighted data

time it calls weighted.mean(). Do you know if there is some way to get summaryBy to pass weights to weighted.mean() only for each group? I suspect this functionality would be a tremendous benefit to R users who regularly work with weighted data, such as myself. Thanks, Solomon Messing

Re: [R] Confirmatory factor analysis problems using sem package (works in Amos)

Thanks John. Can I ask under what function you call optim/nlm? I cannot see how this is done by examining sem. Thanks, -Solomon > -Original Message- > From: John Fox [mailto:j...@mcmaster.ca] > Sent: Monday, July 27, 2009 6:23 PM > To: 'Solomon Messing' >

Re: [R] Confirmatory factor analysis problems using sem package (works in Amos)

Dear John, Would it possible to use a different optimizer with the sem package? Perhaps optim(..., method = c("Nelder-Mead", "BFGS", "CG", "L-BFGS-B", "SANN"),...) for example? Thank you very much, -Solomon > -Original Message- > From: John Fox [mailto:j...@mcmaster.ca] > Sent: Friday