D2Bsplines {cubicBsplines}

Computation of the 2nd derivative of a cubic B-spline basis associated to a given vector of knots

Description

Computation of the 2nd derivative of a cubic B-spline basis associated to a given vector of knots

Usage

D2Bsplines(x, knots)

Arguments

x

vector of values where the 2nd derivative of the B-spline basis must be evaluated.

knots

vector of knots spanning the desired B-spline basis.

Value

A matrix of dimension length(x) by (length(knots)+2).

Each column of the matrix corresponds to (the 2nd derivative of) one cubic B-spline in the basis.

Examples

D2Bsplines(x=runif(20),knots=seq(0,1,length=11))