.BG
.FN tsp
.FN start
.FN end
.FN frequency
.TL
Tsp Attribute of an Object
.CS
tsp(x)
start(x)
end(x)
frequency(x)
.AG x
any object.
.RT
the `tsp' attribute of `x', which will usually be
`NULL' if `x' is not a time-series.
The `tsp' attribute has three values giving the starting time,
ending time, and observation frequency of the time-series.
The `start' and `end' functions return their times as a pair
of numbers: an integer number of time units, and the number
of observations times after that integer.
For example, for monthly series, with `frequency(x)' equal
to 12, these are year and month.
.PP
To explicitly delete the `tsp' attribute,
use `tsp(x) <- NULL'.
.SA
`ts', `tsmatrix'.
.EX
   # assume x is monthly from Jan. 1970 to Jul. 1975
tsp(x)      # is c(1970.0, 1975.5, 12)
start(x)    # is the vector c(1970,1)
end(x)      # is the vector c(1975,7)
frequency(x)     # is 12
xyz <- ts(data, start=start(gnp), frequency=frequency(gnp))
            # create a time-series beginning at same time as gnp
.KW attribute
.WR
