psi_func_cached-class: Class "psi_func_cached"
Description
The class "psi_func_cached" is used to store $\psi \ (psi)$
functions for M-estimation. In particular, an object of the class
contains $\rho(x) \ (\code{rho})$, its derivative
$\psi(x) \ (psi)$, the weight function $\psi(x)/x$, and
first derivative of $\psi$, Dpsi = $\psi'(x)$. The expected values are calculated using numerical integration. For
efficiency reasons, the results are cached. The current implementation
only returns the expectations for the default values and ignores the
arguments.
Objects from the Class
Objects can be created by calls of the form new("psi_func_cached", ...)
but preferably by psiFuncCached(...).Extends
Class "psi_func", directly.Warning
The E... slots will not be fully functional: they just
return the value for the current defaults and ignore
their arguments.