regfun_grad: Beta regularization function gradient
Description
This function computes regularization penalty term gradient based on the betas and difference order.
Usage
regfun_grad(beta, regularization_order = 2)
Arguments
beta
spline parameter vector length num_params
regularization_order
An integer (typically 0, 1, 2), indicating differencing order for L2
regularization of spline parameters. Default is 2 for second derivative penalty.
Value
scalar regularization value