RMpenta is a stationary isotropic covariance model, which is valid only for dimensions
$d \le 3$.
The corresponding covariance function only depends on the distance $r \ge 0$ between
two points and is given by
$$C(r) = (1 - \frac{22}{3}r^{2} + 33 r^{4} - \frac{77}{2} r^{5} + \frac{33}{2} r^{7} - \frac{11}{2} r^{9} + \frac{5}{6}r^{11}) 1_{[0,1]}(r) .$$
Usage
RMpenta(var, scale, Aniso, proj)
Arguments
var,scale,Aniso,proj
optional parameters; same meaning for any
RMmodel. If not passed, the above
covariance function remains unmodified.