1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178
|
##
## R package splines2 by Wenjie Wang and Jun Yan
## Copyright (C) 2016-2021
##
## This file is part of the R package splines2.
##
## The R package splines2 is free software: You can redistribute it and/or
## modify it under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or any later
## version (at your option). See the GNU General Public License at
## <https://www.gnu.org/licenses/> for details.
##
## The R package splines2 is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
##
##' Derivatives of Spline Bases
##'
##' Returns derivatives of given order for the given spline bases.
##'
##' At knots, the derivative is defined to be the right derivative except at the
##' right boundary knot. By default, the function returns the first derivatives.
##' For derivatives of order greater than one, nested function calls such as
##' \code{deriv(deriv(expr))} are supported but not recommended. For a better
##' performance, argument \code{derivs} should be specified instead.
##'
##' This function is designed for objects produced by this package. It
##' internally extracts necessary specification about the spline/polynomial
##' basis matrix from its attributes. Therefore, the function will not work if
##' the key attributes are not available after some operations.
##'
##' @name deriv
##'
##' @param expr Objects of class \code{bSpline2}, \code{ibs}, \code{mSpline},
##' \code{iSpline}, \code{cSpline}, \code{bernsteinPoly} or
##' \code{naturalSpline} with attributes describing \code{knots},
##' \code{degree}, etc.
##' @param derivs A positive integer specifying the order of derivatives. By
##' default, it is \code{1L} for the first derivatives.
##' @param ... Optional argument that are not used.
##'
##' @return A numeric matrix of the same dimension with the input \code{expr}.
##'
##' @example inst/examples/ex-deriv.R
##'
##' @importFrom stats deriv
NULL
##' @rdname deriv
##' @export
deriv.bSpline2 <- function(expr, derivs = 1L, ...)
{
attr(expr, "derivs") <- derivs
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "knots", "Boundary.knots", "intercept"))
do.call(dbs, attributes(expr))
}
##' @rdname deriv
##' @export
deriv.dbs <- function(expr, derivs = 1L, ...)
{
attr(expr, "derivs") <- attr(expr, "derivs") + derivs
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "derivs",
"knots", "Boundary.knots", "intercept"))
do.call(dbs, attributes(expr))
}
##' @rdname deriv
##' @export
deriv.ibs <- function(expr, derivs = 1L, ...)
{
## quick check on derivs
derivs <- as.integer(derivs)
if (derivs < 1L) {
stop("The 'derivs' has to be a positive integer.")
}
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "knots", "Boundary.knots", "intercept"))
## if first derivative, take result from existing attribute if exists
if (derivs == 1L) {
do.call(bSpline, attributes(expr))
} else {
## for higher order of derivative
attr(expr, "derivs") <- derivs - 1L
do.call(dbs, attributes(expr))
}
}
##' @rdname deriv
##' @export
deriv.mSpline <- function(expr, derivs = 1L, ...)
{
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "derivs", "integral", "periodic",
"knots", "Boundary.knots", "intercept"))
attr(expr, "derivs") <- attr(expr, "derivs") + derivs
do.call(mSpline, attributes(expr))
}
##' @rdname deriv
##' @export
deriv.iSpline <- function(expr, derivs = 1L, ...)
{
## quick check on derivs
derivs <- as.integer(derivs)
if (derivs < 1L) {
stop("The 'derivs' has to be a positive integer.")
}
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "derivs",
"knots", "Boundary.knots", "intercept"))
attr(expr, "derivs") <- derivs - 1L
do.call(mSpline, attributes(expr))
}
##' @rdname deriv
##' @export
deriv.cSpline <- function(expr, derivs = 1L, ...)
{
## quick check on derivs
derivs <- as.integer(derivs)
if (derivs < 1L) {
stop("The 'derivs' has to be a positive integer.")
}
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "derivs",
"knots", "Boundary.knots", "intercept"))
scl <- attr(expr, "scales")
## not scaled (then "derivs" must be 0 in cSpline call)
if (is.null(scl)) {
derivs <- as.integer(derivs)
if (derivs == 1L) {
return(do.call(iSpline, attributes(expr)))
}
if (derivs == 2L) {
return(do.call(mSpline, attributes(expr)))
}
attr(expr, "derivs") <- derivs - 2L
do.call(mSpline, attributes(expr))
} else {
## else scaled
attr(expr, "derivs") <- attr(expr, "derivs") + derivs
do.call(cSpline, attributes(expr))
}
}
##' @rdname deriv
##' @export
deriv.bernsteinPoly <- function(expr, derivs = 1L, ...)
{
## checks if key attributes still exist
check_attr(expr, c("x", "degree", "derivs", "integral",
"Boundary.knots", "intercept"))
attr(expr, "derivs") <- attr(expr, "derivs") + derivs
do.call(bernsteinPoly, attributes(expr))
}
##' @rdname deriv
##' @export
deriv.naturalSpline <- function(expr, derivs = 1L, ...)
{
## checks if key attributes still exist
check_attr(expr, c("x", "derivs", "integral",
"knots", "Boundary.knots", "intercept"))
attr(expr, "derivs") <- attr(expr, "derivs") + derivs
do.call(naturalSpline, attributes(expr))
}
|