It is assumed that the instrument clock matches the real time at the start
of the sampling, and that the clock drifts linearly (i.e. is uniformly fast
or slow) over the sampling interval. Linear interpolation is used to infer
the values of all variables in the data slot. The data length is
altered in this process, e.g. a slow instrument clock (positive
slowEnd) takes too few samples in a given time interval, so
undriftTime will increase the number of data.
undriftTime(x, slowEnd = 0, tname = "time")An object of the same class as x, with the data slot
adjusted appropriately.
an oce object.
number of seconds to add to final instrument time, to get the correct time of the final sample. This will be a positive number, for a "slow" instrument clock.
Character string indicating the name of the time column in the
data slot of x.
library(oce)
file <- "~/data/archive/sleiwex/2008/moorings/m08/pt/rbr_011855/raw/pt_rbr_011855.dat"
rbr011855 <- read.oce(file)
d <- subset(rbr011855, time < as.POSIXct("2008-06-25 10:05:00"))
x <- undriftTime(d, 1) # clock lost 1 second over whole experiment
summary(d)
summary(x)
Dan Kelley