interpNA: Interpolate missing values in a Time Indexed Series

Description

Calls approxfun or splinefun to interpolate missing values in a tis object.

Usage

interpNA(x, method = "constant", useTimes = F, offset = 1, rule = 2, f = 0, ...)

Arguments

a tis time series

method

One of c("constant", "linear", "fmm", "natural", "periodic"). Methods "constant" and "linear" call approxfun; the others call splinefun.

useTimes

if TRUE, use time(x, offset) (the decimal times of x) as the 'x' part of the (x, y) pairs used for interpolation. If FALSE (the default), use ti(x) (the integer time indices of x

offset

if useTimes is TRUE, a number in the range
	[0,1] telling where in the periods represented by ti(x) to
	get the points for the 'x' parts of the (x, y) pairs. See the help
	for jul

rule

For methods "constant" and "linear": an integer describing
	how interpolation is to take place outside the interval
	[min(x), max(x)]. If rule is 1 then
	NAs are returned for such points and

f

For method="constant" a number between 0 and 1
    inclusive, indicating a compromise between left- and
    right-continuous step functions. If y0 and y1 are the
    values to the left and right of the point then the

...

Other arguments passed along to approxfun for
	methods "constant" and "linear".

`Value`

A tis object like x with NA values filled
  in by interpolated values.

`Details`

Depending on the method specified, a call to either
  approxfun or splinefun is constructed with appropriate
  arguments and executed for each column of x.  In the call to
  approxfun or splinefun, the time indices ti(x)
  (or the decimal times returned by time(x, offset), if
  useTimes is TRUE) serve as the 'x' argument and the
  column values as the 'y' argument.

`See Also`

approxfun, splinefun,
  ti