Wierd problem comparing numeric values and list using == (PR#1073)
gregory_r_warnes@groton.pfizer.com writes:
Under R 1.3.0 on Solaris and Windows NT there seems to be a bug in == when applied to elements of a list, particularly when one of the elements is of mode integer:
> list(1) == list(1)
[1] FALSE
> 1 == list(1)
[1] TRUE
> as.integer(1)==list(as.integer(1))
[1] FALSE
> as.integer(1)==list(as.double(1))
[1] FALSE
> list(as.integer(1))==list(as.integer(1))
[1] FALSE
> list(as.integer(1))==as.integer(1)
[1] FALSE
> list(as.double(1))==list(as.double(1))
[1] FALSE However, these cases work:
> as.double(1)==list(as.integer(1))
[1] TRUE
> list(as.integer(1))==as.double(1)
[1] TRUE Replacing the bare integer/double with a vector constructed with c() doesn't change the results, and comparing between vectors created with c() appears correct.
It is not entirely clear what we *should* be doing here. S (-PLUS 3.4) is at least consistent:
list(1) == list(1)
Error in list(1) == list(1): == operation on mode "list" undefined Dumped
1 == list(1)
Error in 1 == list(1): == operation on mode "list" undefined Dumped
as.integer(1)==list(as.integer(1))
Error in as.integer(1) == list(as.integer(1)): == operation on mode "list"
undefined
Dumped
...
so one might argue that you shouldn't do that in the first place...
(or that the bug is that we do not expressly forbid doing this.)
-p
O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard@biostat.ku.dk) FAX: (+45) 35327907 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._