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pomp (version 1.10)

B-splines: B-spline bases

Description

These functions generate B-spline basis functions. bspline.basis gives a basis of spline functions. periodic.bspline.basis gives a basis of periodic spline functions.

Usage

bspline.basis(x, nbasis, degree = 3, names = NULL) periodic.bspline.basis(x, nbasis, degree = 3, period = 1, names = NULL)

Arguments

x
Vector at which the spline functions are to be evaluated.
nbasis
The number of basis functions to return.
degree
Degree of requested B-splines.
period
The period of the requested periodic B-splines.
names
optional; the names to be given to the basis functions. These will be the column-names of the matrix returned. If the names are specified as a format string (e.g., "basis%d"), sprintf will be used to generate the names from the column number. If a single non-format string is specified, the names will be generated by paste-ing name to the column number. One can also specify each column name explicitly by giving a length-nbasis string vector. By default, no column-names are given.

Value

C API

Access to the underlying C routines is available: see the header file pomp.h for definition and documentation of the C API. At an R prompt, execute
file.show(system.file("include/pomp.h",package="pomp"))
to view this file.

Examples

Run this code
x <- seq(0,2,by=0.01)
y <- bspline.basis(x,degree=3,nbasis=9,names="basis")
matplot(x,y,type='l',ylim=c(0,1.1))
lines(x,apply(y,1,sum),lwd=2)

x <- seq(-1,2,by=0.01)
y <- periodic.bspline.basis(x,nbasis=5,names="spline%d")
matplot(x,y,type='l')

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