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?? Thank you again, Theodore _______________________________________________ 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
