On 5 October 2012 at 23:55, Theodore Lytras wrote: | Στις Παρ 05 Οκτ 2012, ο/η Dirk Eddelbuettel έγραψε: | > On 5 October 2012 at 21:39, Theodore Lytras wrote: | > | Hello all, | > | | > | I am trying to pass from C++ to R a DateVector with a few missing items | > | (NAs). I can't seem to find a way, though. | > | There does not seem to be a NA_DATE (like NA_REAL, etc), and the default | > | constructor for Rcpp::Date creates a date of "-5877641-06-23". | [snip] | > I've never tried this, but as Dates in R really are just integers since the | > epoch -- so maybe the NA_INTEGER aka R_NaInt will work? | | I tried this already - it doesn't. | Neither do the other constants (NA_REAL and NA_LOGICAL). | I also tried Rcpp::Date(NA_INTEGER). | They all create a date of "-5877641-06-23". | | > At a more conceptual level, NA shouldn't really be in dates, right? Either | > is a valid date, or it is missing (NULL). There simply is no such thing as | > Feb 30 or April 31. | | Not really, because NA is the natural choice to indicate a missing value. If | for example one has a vector with 10 date observations and wants to indicate | that the 3rd is missing, one has to use NA. With NULL one gets a vector of | size 9. NA is necessary to have for all data types. | | And it is supported in the R interpreter, for example: | | a <- as.Date(c(3883, NA, 15120), origin="1970-1-1") | a | [1] "1980-08-19" NA "2011-05-26" | | Shouldn't there be a special value (like R_NaInt) or a special object or | something, that represents NA dates??
Maybe. Feel like working on a patch? src/RcppDate.cpp is pretty straightforward and mostly free of template magic. It may just need a layer of NA testing I didn't add when I wrote that. I am with you as R can do this: R> as.Date(c(1,2,NA,777)) [1] "1970-01-02" "1970-01-03" NA "1972-02-17" R> maybe Rcpp should too. But you're the one with the itch to scratch... so help would be appreciated. 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
