I am trying to figure out a way to add a certain number of hours to a
date/time stamp.
Specifically, I have a string of date/time stamps that all have the time at
midnight.  I would like to be able to keep the date the same, but add a
certain number of hours to create a new timestamp that is a few hours
later.


Below is the procedure I have tried so far with no luck:

startDate <- "2008-11-01"
endDate <- "2008-11-05"
OutDates <- seq(as.Date(startDate), as.Date(endDate), by="day")
> OutDates
"2008-11-01" "2008-11-02" "2008-11-03" "2008-11-04" "2008-11-05"

FourOclock <- as.difftime("16:00:00")
> FourOclock
Time difference of 16 hours


Afternoons <- OutDates + FourOclock
> Afternoons
 "2008-11-17" "2008-11-18" "2008-11-19" "2008-11-20" "2008-11-21"
Gives the wrong answer, adding 16 days instead of 16 hours, and throws the
following warning:
Warning message:
Incompatible methods ("+.Date", "Ops.difftime") for "+"


I am stumped on this one and would appreciate any/all recommendations.
Thanks!

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