| na.locf {zoo} | R Documentation |
Generic function for replacing each NA with the most recent
non-NA prior to it.
na.locf(object, na.rm = TRUE, ...) ## Default S3 method: na.locf(object, na.rm = TRUE, fromLast, rev, ...)
object |
an object. |
na.rm |
logical. Should leading NAs be removed? |
fromLast |
logical. Causes observations to be carried backward rather
than forward. Default is FALSE.
This corresponds to NOCB (next observation carried backward). |
rev |
Use fromLast instead. This argument will
be eliminated in the future in favor of fromLast. |
... |
further arguments passed to methods. |
An object in which each NA in the input object is replaced
by the most recent non-NA prior to it. If there are no earlier non-NAs then
the NA is omitted (if na.rm = TRUE) or it is not replaced (if na.rm = FALSE).
Note that if a multi-column zoo object has a column entirely composed of
NA then with na.rm=TRUE, the default,
the above implies that the resulting object will have
zero rows. Use na.rm=FALSE to preserve the NA values instead.
az <- zoo(1:6)
bz <- zoo(c(2,NA,1,4,5,2))
na.locf(bz)
na.locf(bz, fromLast = TRUE)
cz <- zoo(c(NA,9,3,2,3,2))
na.locf(cz)
# generate and fill in missing dates
# by merging with a zero width series having those dates
# and then applying na.locf
z <- zoo(c(0.007306621, 0.007659046, 0.007681013,
0.007817548, 0.007847579, 0.007867313),
as.Date(c("1993-01-01", "1993-01-09", "1993-01-16",
"1993-01-23", "1993-01-30", "1993-02-06")))
dd <- seq(start(z), end(z), "day")
na.locf(merge(z, zoo(, dd)))