Predict time-varying parameters using splines.
spline_par(par, n, knots = NULL, periodic = FALSE, period = NULL)
Values at knots
Number of points. Time (independent variable) is assumed to be between 0 and n with length(par) equidistant points (including 0 and n).
Position of knots. Default, is length(x) equidistant points between 0 and 1. Always are re-scaled to 0 to 1.
boolean, is the spline periodic?
If periodic is TRUE, it specify the time period.
A list with the interpolates values as 'x' and 'time'.