monomialpen: Evaluate Monomial Roughness Penalty Matrix

View source: R/monomialpen.R

monomialpenR Documentation

Evaluate Monomial Roughness Penalty Matrix

Description

The roughness penalty matrix is the set of inner products of all pairs of a derivative of integer powers of the argument.

Usage

monomialpen(basisobj, Lfdobj=int2Lfd(2),
            rng=basisobj$rangeval)

Arguments

basisobj

a monomial basis object.

Lfdobj

either a nonnegative integer specifying an order of derivative or a linear differential operator object.

rng

the inner product may be computed over a range that is contained within the range defined in the basis object. This is a vector or length two defining the range.

Value

a symmetric matrix of order equal to the number of monomial basis functions.

See Also

exponpen, fourierpen, bsplinepen, polygpen

Examples

##
## set up a monomial basis for the first five powers
##
nbasis   <- 5
basisobj <- create.monomial.basis(c(-1,1),nbasis)
#  evaluate the rougness penalty matrix for the
#  second derivative.
penmat <- monomialpen(basisobj, 2)

##
## with rng of class Date and POSIXct
##
# Date
invasion1 <- as.Date('1775-09-04')
invasion2 <- as.Date('1812-07-12')
earlyUS.Canada <- c(invasion1, invasion2)
BspInvade1 <- create.monomial.basis(earlyUS.Canada)
invadmat <- monomialpen(BspInvade1)

# POSIXct
AmRev.ct <- as.POSIXct1970(c('1776-07-04', '1789-04-30'))
BspRev1.ct <- create.monomial.basis(AmRev.ct)
revmat <- monomialpen(BspRev1.ct)


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