norder: Order of a B-spline

Description

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

Usage

norder(x, ...)
# S3 method for fd
norder(x, ...)
# S3 method for basisfd
norder(x, ...)
# S3 method for default
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 bspline
norder(x, ...)

Arguments

Either a basisfd object or an object containing a basisfd object as a component.

…

optional arguments currently unused

Value

An integer giving the order of the B-spline.

Details

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

Examples

Run this code

# NOT RUN {
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.
# }
# 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)

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

# }
# NOT RUN {
norder(create.fourier.basis(c(0,12) ))
Error in norder.bspline(x) :
  object x is of type = fourier;  'norder' is only defined for type = 'bsline'
# }
# NOT RUN {
# }