time
Create Time Vector or Index of Frequency
Description
Returns a univariate time series or other object
giving either the time point or the
position in a cycle of a time series.
Usage
time(x, ...)
## Default S3 method:
time(x, offset = 0, ...)
cycle(x, ...)
## Default S3 method:
cycle(x, ...)
Arguments
x |
A time series object or something like a vector or matrix that as.ts() can convert to a time series.
|
offset |
A number to add to the usual output. It is interpreted as
a fraction of deltat(x).
|
... |
other arguments passed to or from methods or future functions.
|
Value
For
x of class
ts, both
time(x) and
cycle(x) return a univariate
time series:
- time(x) containing the times of the observations in x.
- cycle(x) giving the position within a cycle of each observation (for example, the month number,
starting with 1, when frequency(x) is 12).
If
x is not a time series object, then it is converted to one with
as.ts(x) and
treated as described above.
See Also
Examples
# Earnings/share of hypothetical public company
eps <- ts(c(2.43, 2.67, 2.50, 2.44, 2.47, 2.73, 2.55, 2.49, 2.55, 2.79),
frequency=4, start=2010.25)
time(eps)
# fiscal year starts Dec. 1, 2/3 of way through a calendar quarter,
# so use the offset argument:
time(eps, offset=2/3)
cycle(eps)
tapply(eps, cycle(eps), median) # median earnings by quarter