Hi all, I noticed that `range.default()` has a nice `finite = TRUE` argument, but it doesn't actually apply to Date or POSIXct due to how `is.numeric()` works.
``` x <- .Date(c(0, Inf, 1, 2, Inf)) x #> [1] "1970-01-01" "Inf" "1970-01-02" "1970-01-03" "Inf" # Darn! range(x, finite = TRUE) #> [1] "1970-01-01" "Inf" # What I want .Date(range(unclass(x), finite = TRUE)) #> [1] "1970-01-01" "1970-01-03" ``` I think `finite = TRUE` would be pretty nice for Dates in particular. As a motivating example, sometimes you have ranges of dates represented by start/end pairs. It is fairly natural to represent an event that hasn't ended yet with an infinite date. If you need to then compute a sequence of dates spanning the full range of the start/end pairs, it would be nice to be able to use `range(finite = TRUE)` to do so: ``` start <- as.Date(c("2019-01-05", "2019-01-10", "2019-01-11", "2019-01-14")) end <- as.Date(c("2019-01-07", NA, "2019-01-14", NA)) end[is.na(end)] <- Inf # `end = Inf` means that the event hasn't "ended" yet data.frame(start, end) #> start end #> 1 2019-01-05 2019-01-07 #> 2 2019-01-10 Inf #> 3 2019-01-11 2019-01-14 #> 4 2019-01-14 Inf # Create a full sequence along all days in start/end range <- .Date(range(unclass(c(start, end)), finite = TRUE)) seq(range[1], range[2], by = 1) #> [1] "2019-01-05" "2019-01-06" "2019-01-07" "2019-01-08" "2019-01-09" #> [6] "2019-01-10" "2019-01-11" "2019-01-12" "2019-01-13" "2019-01-14" ``` It seems like one option is to create a `range.Date()` method that unclasses, forwards the arguments on to a second call to `range()`, and then reclasses? ``` range.Date <- function(x, ..., na.rm = FALSE, finite = FALSE) { .Date(range(unclass(x), na.rm = na.rm, finite = finite), oldClass(x)) } ``` This is similar to how `rep.Date()` works. Thanks, Davis Vaughan ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel