time {stats} | R Documentation |
time
creates the vector of times at which a time series was sampled.
cycle
gives the positions in the cycle of each observation.
frequency
returns the number of samples per unit time and
deltat
the time interval between observations (see
ts
).
time(x, ...) ## Default S3 method: time(x, offset=0, ...) cycle(x, ...) frequency(x, ...) deltat(x, ...)
x |
a univariate or multivariate time-series, or a vector or matrix. |
offset |
can be used to indicate when sampling took place
in the time unit. 0 (the default) indicates the start
of the unit, 0.5 the middle and 1 the end of
the interval. |
... |
extra arguments for future methods. |
These are all generic functions, which will use the
tsp
attribute of x
if it exists. time
and cycle
have methods for class ts
that coerce
the result to that class.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
date
for clock time, system.time
for CPU usage.
cycle(presidents) # a simple series plot: c() makes the x and y arguments into vectors plot(c(time(presidents)), c(presidents), type="l")