window.zoo {zoo} | R Documentation |
Methods for extracting time windows
of "zoo"
objects and replacing it.
## S3 method for class 'zoo': window(x, index. = index(x), start = NULL, end = NULL, ...) ## S3 method for class 'zoo': window(x, index. = index(x), start = NULL, end = NULL, ...) <- value
x |
an object. |
index. |
the index/time window which should be extracted. |
start |
an index/time value. Only the indexes in index
which are greater or equal to start are used. If the index
class supports comparisons to character variables, as does "Date"
class, "yearmon" class, "yearqtr" class and
the chron package classes "dates" and "times"
then start may alternately be a character variable. |
end |
an index/time value. Only the indexes in index
which are lower or equal to end are used. Similar comments
about character variables mentioned under start apply
here too. |
value |
a suitable value object for use with window(x) . |
... |
currently not used. |
Either the time window of the object is extracted (and hence return a "zoo"
object) or it is replaced.
## zoo example x.date <- as.Date(paste(2003, rep(1:4, 4:1), seq(1,19,2), sep = "-")) x <- zoo(matrix(rnorm(20), ncol = 2), x.date) x window(x, start = as.Date("2003-02-01"), end = as.Date("2003-03-01")) window(x, index = x.date[1:6], start = as.Date("2003-02-01")) window(x, index = x.date[c(4, 8, 10)]) window(x, index = x.date[c(4, 8, 10)]) <- matrix(1:6, ncol = 2) x ## for classes that support comparisons with "character" variables ## start and end may be "character". window(x, start = "2003-02-01") ## zooreg example (with plain numeric index) z <- zooreg(rnorm(10), start = 2000, freq = 4) window(z, start = 2001.75) window(z, start = c(2001, 4)) ## replace data at times of d0 which are in dn d1 <- d0 <- zoo(1:10) + 100 dn <- - head(d0, 4) window(d1, time(dn)) <- coredata(dn)