norder: Order of a B-spline

In fda: Functional Data Analysis

Order of a B-spline

Description

norder = number of basis functions minus the number of interior knots.

Usage

norder(x, ...)
## S3 method for class 'fd'
norder(x, ...)
## S3 method for class 'basisfd'
norder(x, ...)
## Default S3 method:
norder(x, ...)

#norder.bspline(x, ...)

#NOTE:  The following is required by CRAN rules that
# function names like "as.numeric" must follow the documentation
# standards for S3 generics, even when they are not.
# Please ignore the following line:
## S3 method for class 'bspline'
norder(x, ...)

Arguments

x	Either a basisfd object or an object containing a basisfd object as a component.
...	optional arguments currently unused

Details

norder throws an error of basisfd[['type']] != 'bspline'.

Value

An integer giving the order of the B-spline.

Author(s)

Spencer Graves

See Also

create.bspline.basis

Examples

  bspl1.1 <- create.bspline.basis(norder=1, breaks=0:1)

  stopifnot(norder(bspl1.1)==1)

  stopifnot(norder(fd(0, basisobj=bspl1.1))==1)

  stopifnot(norder(fd(rep(0,4)))==4)

  stopifnot(norder(list(fd(rep(0,4))))==4)
  ## Not run: 
    norder(list(list(fd(rep(0,4)))))
    Error in norder.default(list(list(fd(rep(0, 4))))) :
    input is not a 'basisfd' object and does not have a 'basisfd'
    component.
  
## End(Not run)

  stopifnot(norder(create.bspline.basis(norder=1, breaks=c(0,.5, 1))) == 1)

  stopifnot(norder(create.bspline.basis(norder=2, breaks=c(0,.5, 1))) == 2)

  # Default B-spline basis:  Cubic spline:  degree 3, order 4,
  # 21 breaks, 19 interior knots.
  stopifnot(norder(create.bspline.basis()) == 4)

  # these five lines throw an error of for a nocran check 
  # if (!CRAN()) {
  #   norder(create.fourier.basis(c(0,12) ))
    # Error in norder.bspline(x) :
    # object x is of type = fourier;  'norder' is only defined for type = 'bspline'
  # }

fda documentation built on May 31, 2023, 9:19 p.m.