I am trying to write a C++ function to be called from R and have never done this before. I have done the following: require(Rcpp) require(inline) src <- 'blahblahblah' fun <- cxxfunction(signature(a="numeric",b="numeric"),src,plugin="Rcpp") That last line generates the error message: Error in compileCode(f, code, language = language, verbose = verbose) : Compilation ERROR, function(s)/method(s) not created! In addition: Warning message: running command 'C:/PROGRA~1/R/R-215~1.1/bin/i386/R CMD SHLIB file26476eb7fd0.cpp 2> file26476eb7fd0.cpp.txt' had status 1 I am assuming that I don't have the necessary compiler installed on my machine. I tried installing Rtools, which created a C:/Rtools/ directory with the files, but I am not sure if my R software knows how to properly access it. I was advised to make sure my path is set correctly, but wasn't sure which path--my library search path in R, my Rtools installation setting for "PATH", my "PATH" in DOS, or what. I am operating on Windows 7. I would greatly appreciate some instructions on how to set this up. All the manuals and posts seem to gloss over the details of setting up the C++ compiler (I have looked at The Art of R Programming, and also the R-admin.pdf file, among other sources). I assume it is something that can be done in 5 minutes, if I only knew how ... Thanks. [[alternative HTML version deleted]]