## S3 method for class 'zoo':
merge(\dots, all = TRUE, fill = NA, suffixes = NULL,
retclass = c("zoo", "list", "data.frame"))
"zoo"
."zoo"
objects to be merged (otherwise expanded)."zoo"
objects (if any)."zoo"
objects specifying the suffixes to be used for making
the merged column names unique."zoo"
(the default), "list"
or NULL
. For
details see below.merge
method for "zoo"
objects combines the columns
of several objects along the union of the dates
for all = TRUE
, the default,
or the intersection of their dates for all = FALSE
filling up the created gaps (if any) with the fill
pattern.The first argument must be a zoo
object. If any of the remaining
arguments are plain vectors or matrices with the same length or number
of rows as the first argument then such arguments are coerced to "zoo"
using as.zoo
. If they are plain but have length 1 then they are
merged after all non-scalars such that their column is filled with the
value of the scalar.
all
can be a vector of the same length as the number of "zoo"
objects to merged (if not, it is expanded): All indexes
(times) of the objects corresponding to TRUE
are included, for those
corresponding to FALSE
only the indexes present in all objects are
included. This allows intersection, union and left and right joins
to be expressed.
If retclass
is "zoo"
(the default) a single merged "zoo"
object is returned. If it is set to "list"
a list of "zoo}
objects is returned. If code{retclass = NULL} then instead of returning a value it updates each
argument (if it is a variable rather than an expression) in
place so as to extend or reduce it to use the common index vector.
The indexes of different code{"zoo"} objects can be of different classes and are coerced to one class in the resulting object (with a warning).
The default code{cbind} method is essentially the default code{merge} method, but does not support the code{retclass} argument. The code{rbind} method combines the dates of the code{"zoo"} objects (duplicate dates are not allowed) and combines the rows of the objects. Furthermore, the code{c} method is identical to the code{rbind} method. }
"zoo"
if retclass="zoo"
, an object of
class "list"
if retclass="list"
or modified arguments as
explained above if retclass=NULL
. If the result is an object
of class "zoo"
then its frequency is the common frequency of its
zoo arguments, if they have a common frequency.
seealso{code{zoo}}
examples{ ## simple merging x.date <- as.Date(paste(2003, 02, c(1, 3, 7, 9, 14), sep = "-")) x <- zoo(rnorm(5), x.date)
y1 <- zoo(matrix(1:10, ncol = 2), 1:5) y2 <- zoo(matrix(rnorm(10), ncol = 2), 3:7)
## using arguments `fill' and `suffixes' merge(y1, y2, all = FALSE) merge(y1, y2, all = FALSE, suffixes = c("a", "b")) merge(y1, y2, all = TRUE) merge(y1, y2, all = TRUE, fill = 0)
## if different index classes are merged, as in ## the next merge example then ## a warning is issued and ### the indexes are coerced. ## It is up to the user to ensure that the result makes sense. merge(x, y1, y2, all = TRUE)
## extend an irregular series to a regular one: # create a constant series z <- zoo(1, seq(4)[-2]) # create a 0 dimensional zoo series z0 <- zoo(, 1:4) # do the extension merge(z, z0) # same but with zero fill merge(z, z0, fill = 0)
merge(z, coredata(z), 1) } keyword{ts}