# Extract/Replacing the Time Windows of Objects Methods for extracting time windows of `"zoo"` objects and replacing it. ```r ## S3 method for class 'zoo' window(x, index. = index(x), start = NULL, end = NULL, ...) ## S3 replacement method for class 'zoo' window(x, index. = index(x), start = NULL, end = NULL, ...) <- value ``` ## Arguments - `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. ## Returns Either the time window of the object is extracted (and hence return a `"zoo"` object) or it is replaced. ## See Also `zoo` ## Examples ```r suppressWarnings(RNGversion("3.5.0")) set.seed(1) ## 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) ## if the underlying time index is a float, note that the index may ## print in the same way but actually be different (e.g., differing ## by 0.1 second in this example) zp <- zoo(1:4, as.POSIXct("2000-01-01 00:00:00") + c(-3600, 0, 0.1, 3600)) ## and then the >= start and <= end may not select all intended ## observations and adding/subtracting some "fuzz" may be needed window(zp, end = "2000-01-01 00:00:00") window(zp, end = as.POSIXct("2000-01-01 00:00:00") + 0.5) ```

window.zoo function