Returns for (each of) the given timestamp(s) the timestamp(s) itself if it represents a multiple of the given time step or the nearest smaller or nearest greater timestamp that represents a multiple of the time step.
roundTime(tstamp, tstep, direction = -1)
| tstamp | (vector of) timestamp(s) of class "POSIXlt" or "POSIXct" |
|---|---|
| tstep | time step in seconds of which timestamps in tstamp shall represent multiples |
| direction | one of -1, 0, 1. If -1, the nearest timestamp (either smaller or greater) complying with the timestamp is returned. If 0, always the nearest greater timestamp and if 1, always the nearest smaller timestamp is returned. |
(Vector of) timestamp(s) corresponding to timestamp(s) given in tstamp being “rounded” to the nearest --- greater or smaller (direction == -1), always smaller (direction == 1) or always greater (direction == 0) --- timestamp representing a multiple of the given time step tstep.
# Generate a timestamp to be "rounded" t0 <- hsToPosix("2011-12-24 18:22:05") # Round to nearest (default) full minute roundTime(t0, 60) ## = 2011-12-24 18:22:00 UTC#> [1] "2011-12-24 18:22:00 UTC"# Round to nearest full greater minute roundTime(t0, 60, 0) ## = 2011-12-24 18:23:00 UTC#> [1] "2011-12-24 18:23:00 UTC"# Round to nearest multiple of 15 minutes (-1 could be omitted) roundTime(t0, 15*60, -1) ## 2011-12-24 18:15:00 UTC#> [1] "2011-12-24 18:15:00 UTC"# Round to nearest smaller multiple of four hours roundTime(t0, 4*60*60, 1) ## 2011-12-24 16:00:00 UTC#> [1] "2011-12-24 16:00:00 UTC"