mixAK: BsBasis – R documentation

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BsBasis

B-spline basis

Description

It creates a B-spline basis based on a specific dataset. B-splines are assumed to have common boundary knots and equidistant inner knots.

Usage

BsBasis(degree, ninner, knotsBound, knots, intercept=FALSE,
        x, tgrid, Bname="B", plot=FALSE, lwd=1,
        col="blue", xlab="Time", ylab="B(t)",
        pch=16, cex.pch=1, knotcol="red")

Arguments

`degree`	degree of the B-spline.
`ninner`	number of inner knots.
`knotsBound`	2-component vector with boundary knots.
`knots`	knots of the B-spline (including boundary ones). If `knots` is given `ninner` and `knotsBound` are ignored.
`intercept`	logical, if `FALSE`, the first basis B-spline is removed from the B-spline basis and it is assumed that intercept is added to the statistical models used afterwards.
`x`	a numeric vector to be used to create the B-spline basis.
`tgrid`	if given then it is used to plot the basis.
`Bname`	label for the created columns with the B-spline basis.
`plot`	logical, if `TRUE` the B-spline basis is plotted.
`lwd, col, xlab, ylab`	arguments passed to the plotting function.
`pch, cex.pch`	plotting character and cex used to plot knots
`knotcol`	color for knots on the plot with the B-spline basis.

Value

A matrix with the B-spline basis. Number of rows is equal to the length of x.

Additionally, the resulting matrix has attributes:

`degree`	B-spline degree
`intercept`	logical indicating the presence of the intercept B-spline
`knots`	a numeric vector of knots
`knotsInner`	a numeric vector of innner knots
`knotsBound`	a numeric vector of boundary knots
`df`	the length of the B-spline basis (number of columns of the resulting object).
`tgrid`	a numeric vector which can be used on `x`-axis to plot the basis.
`Xgrid`	a matrix with `length(tgrid)` rows and `df` columns which can be used to plot the basis.

Author(s)

Arnošt Komárek arnost.komarek[AT]mff.cuni.cz

Examples

set.seed(20101126)
t <- runif(20, 0, 100)

oldPar <- par(mfrow=c(1, 2), bty="n")
Bs <- BsBasis(degree=3, ninner=3, knotsBound=c(0, 100), intercept=FALSE,
              x=t, tgrid=0:100, plot=TRUE)
print(Bs)

Bs2 <- BsBasis(degree=3, ninner=3, knotsBound=c(0, 100), intercept=TRUE,
               x=t, tgrid=0:100, plot=TRUE)
print(Bs2)
par(oldPar)

print(Bs)
print(Bs2)

mixAK

Multivariate Normal Mixture Models and Mixtures of Generalized Linear Mixed Models Including Model Based Clustering

v5.3

GPL (>= 3)

Authors

Arnošt Komárek <arnost.komarek@mff.cuni.cz>

Initial release

2020-06-02