Is the bug-reporting system working okay? Two days ago, I submitted
the following bug report via email to r-bugs at r-project.org. I didn't
see a confirmation, and it didn't see it at
http://bugs.r-project.org/. Now, http://bugs.r-project.org/ seems to
be down.
Anyway, here's the bug report related to sort.list and sort(...,
index.return = TRUE) with na.last = NA
I think that both sort.list(x, na.last = NA) and sort(x, na.last = NA,
index.return = TRUE)$ix give incorrect answers with na.last. With
na.last, both of these return answers equivalent to
sort.list(na.omit(x)), and I think they should be the equivalent of
order(x, na.last=NA) as follows.
x <- c(1L, 6L, NA, 2L)
order(x, na.last = NA) # right
sort.list(x, na.last = NA, method = "radix") # wrong, I think
sort.list(x, na.last = NA, method = "quick") # wrong
sort(x, na.last = NA, index.return = TRUE)$ix # wrong
[1] 1 3 2
I've included a patch for the "radix" and "shell" methods of
sort.list. The sort and "quick" method of sort.list (which uses sort)
look more challenging. With the patch, I get:
sort.list(x, na.last = NA, method = "radix") # good
sort.list(x, na.last = NA, method = "shell") # good
sort.list(x, na.last = NA, method = "quick") # still bad
[1] 1 3 2
By the way, having the radix sort is great. It's really fast for factors.
- Tom
Tom Short
Electric Power Research Institute (EPRI)
R version 2.10.1 (2009-12-14)
i386-pc-mingw32
locale:
[1] LC_COLLATE=English_United States.1252
[2] LC_CTYPE=English_United States.1252
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C
[5] LC_TIME=English_United States.1252
attached base packages:
[1] stats graphics grDevices utils datasets methods base