| na.approx {zoo} | R Documentation |
Generic functions for replacing each NA with interpolated
values.
na.approx(object, ...) ## Default S3 method: na.approx(object, along = index(object), na.rm = TRUE, ...) na.spline(object, ...) ## Default S3 method: na.spline(object, along = index(object), na.rm = TRUE, ...)
object |
object in which NAs are to be replaced |
along |
variable to use for interpolation. Has to be numeric, is otherwise coerced to numeric. |
na.rm |
logical. Should leading NAs be removed? |
... |
further arguments passed to methods. |
Missing values (NAs) are replaced by linear interpolation via
approx or cubic spline interpolation via spline,
respectively.
By default the index associated with object is used
for interpolation. Note, that if this calls index.default
this gives an equidistant spacing 1:NROW(object). If object
is a matrix or data.frame, the interpolation is done separately for
each column.
An object in which each NA in the input object is replaced
by interpolating the non-NA values before and after it.
Leading NAs are omitted (if na.rm = TRUE) or not replaced (if na.rm = FALSE).
zoo, approx, na.contiguous, link{na.locf}, na.omit, na.trim, spline, stinterp
z <- zoo(c(2,NA,1,4,5,2), c(1,3,4,6,7,8)) ## use underlying time scale for interpolation na.approx(z) ## use equidistant spacing na.approx(z, 1:6) # with and without na.rm = FALSE zz <- c(NA,9,3,NA,3,2) na.approx(zz, na.rm = FALSE) na.approx(zz)