Jeffrey Horner wrote:> Hello,
>
> ?DateTimeClasses states that "one can add or subtract a number of
> seconds or a 'difftime' object from a date-time object, but not add
two
> date-time objects."
>
> So, is the below expected behavior?
>
> > x <- Sys.time()
> > x
> [1] "2007-02-21 16:19:56 CST"
> > x + as.difftime("1","%H")
> [1] "2007-02-21 16:19:57 CST"
> Warning message:
> Incompatible methods ("+.POSIXt", "Ops.difftime") for
"+"
>
> "+.POSIXt" does behave as expected, though:
>
> > "+.POSIXt"(x,as.difftime("1","%H"))
> [1] "2007-02-21 17:19:56 CST"
>
> > R.version
> _
> platform i686-pc-linux-gnu
> arch i686
> os linux-gnu
> system i686, linux-gnu
> status Under development (unstable)
> major 2
> minor 5.0
> year 2007
> month 01
> day 07
> svn rev 40398
> language R
> version.string R version 2.5.0 Under development (unstable) (2007-01-07
> r40398)
Oops! I thought I ran this on the latest revision, but the same behavior
is exhibited in r40774:
> x <- Sys.time()
> x
[1] "2007-02-21 16:44:16 CST"
> x + as.difftime("1","%H")
[1] "2007-02-21 16:44:17 CST"
Warning message:
Incompatible methods ("+.POSIXt", "Ops.difftime") for
"+"
> R.version
_
platform i686-pc-linux-gnu
arch i686
os linux-gnu
system i686, linux-gnu
status Under development (unstable)
major 2
minor 5.0
year 2007
month 02
day 21
svn rev 40774
language R
version.string R version 2.5.0 Under development (unstable) (2007-02-21
r40774)
Jeff
--
http://biostat.mc.vanderbilt.edu/JeffreyHorner