Hello, I'm implementing a package (C-extension), where one function gets data and a function that needs to be applied to the data.
I want to apply the function to (parts of) the data on the C-side. 1) how do I apply a function (given via SEXP) to data 2) how do I select parts of the data? Comment on 2: I want to implement a moving/rolling/running apply on the data, so I want to select a data window. How can this be done, and how can it be done efficiently? For example on page 101 of "Writing R extensions" there was a trick on how to use REAL on the result, before using it in a loop. Can this be used for efficiency reasons in general? What do these macros do? Do they convert data or cast datatypes? Ciao, Oliver ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.