Lwls2DDeriv: Two dimensional local linear kernel smoother to target...
In fdapace: Functional Data Analysis and Empirical Dynamics

Lwls2DDeriv

R Documentation

Two dimensional local linear kernel smoother to target derivatives.

Description

Two dimensional local weighted least squares smoother. Only a local linear smoother for estimating the original curve is available (no higher order)

Usage

Lwls2DDeriv(
  bw,
  kern = "epan",
  xin,
  yin,
  win = NULL,
  xout1 = NULL,
  xout2 = NULL,
  xout = NULL,
  npoly = 1L,
  nder1 = 0L,
  nder2 = 0L,
  subset = NULL,
  crosscov = TRUE,
  method = "sort2"
)

Arguments

`bw`	A scalar or a vector of length 2 specifying the bandwidth.
`kern`	Kernel used: 'gauss', 'rect', 'gausvar', 'epan' (default), 'quar'.
`xin`	An n by 2 data frame or matrix of x-coordinate.
`yin`	A vector of y-coordinate.
`win`	A vector of weights on the observations.
`xout1`	a p1-vector of first output coordinate grid. Defaults to the input gridpoints if left unspecified.
`xout2`	a p2-vector of second output coordinate grid. Defaults to the input gridpoints if left unspecified.
`xout`	alternative to xout1 and xout2. A matrix of p by 2 specifying the output points (may be inefficient if the size of `xout` is small).
`npoly`	The degree of polynomials (include all `x^a y^b` terms where `a + b <= npoly`)
`nder1`	Order of derivative in the first direction
`nder2`	Order of derivative in the second direction
`subset`	a vector with the indices of x-/y-/w-in to be used (Default: NULL)
`crosscov`	using function for cross-covariance estimation (Default: TRUE)
`method`	should one try to sort the values xin and yin before using the lwls smoother? if yes ('sort2' - default for non-Gaussian kernels), if no ('plain' - fully stable; de)