polygpen | Language Reference for FDA Library
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polygpen(basisobj, Lfdobj=int2Lfd(1))
a roughness penalty for a function x(t) is defined by integrating the square of either the derivative of x(t) or, more generally, the result of applying a linear differential operator L to it. The only roughness penalty possible aside from penalizing the size of the function itself is the integral of the square of the first derivative, and this is the default. To apply this roughness penalty, the matrix of inner products produced by this function is necessary.
# set up a sequence of 11 argument values argvals <- seq(0,1,0.1) # set up the polygonal basis basisobj <- create.polygonal.basis(argvals) # compute the 11 by 11 penalty matrix penmat <- polygpen(basisobj)