On 15 January 2013 at 07:20, John Merrill wrote: | It appears that DataFrame::create is a thin layer on top of the R data.frame | call. The guarantee correctness, but also means the performance of an Rcpp | routine which returns a large data frame is limited by the performance of | data.frame -- which is utterly horrible.
All correct. It really mostly a convenience layer. When we use R, we think of data.frame objects as accessible by row -- which is not something we can easily do at the C++ layer. So the DataFrame class is really mostly a wrapper around a list (as it is internally) with a call to R to set it. | In the current version of R, there's a trivial, but borderline evil, work | around: build a list of lists meeting the basic requirements of a data frame | (they all need to be of the same length, and each component list needs to be | named) and set the type of the object to "data.frame". | | I have two questions: | (1) Is it reasonable to anticipate that this hack will continue to work for the | near future in R? We cannot speak for R Core. But this is so fundamental to so many things that I (personally speaking) am inclined to say yes. (Or did you mean Rcpp instead of R? If so, example code?) | (2) If so, would a patch to that effect be of interest to the developers? We are always open to reasonable patches to bring improvements (and come with test cases demonstrating usefulness and a testing framework). As I recall there is also an open bug in our DataFrame right now, so if you want to work on it, great :) Dirk -- Dirk Eddelbuettel | e...@debian.org | http://dirk.eddelbuettel.com _______________________________________________ Rcpp-devel mailing list Rcpp-devel@lists.r-forge.r-project.org https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
