Fun(x, x0, samples)
or
density dens(x, x0, samples)
.
Samples should contain samples from the posterior distribution of the parameters.
pred.base(samples, Fun, dens, len = 100, x0, method = c("vector", "free"), pred.alg = c("Distribution", "Trajectory"), sampling.alg = c("RejSamp", "InvMethod"), candArea, grid = 0.001)