Call R native function 'nlminb' to perform optimization.
Nlminb(ml, strt.lims)A list with following named components:
par = parameters
loglik = objective function value at minimum
convergence = 0 for yes, other for no
iterations = number of iterations
evaluations = function evaluations
message = a convergence message
varcovar = a variance covariance matrix of parameters
limits = low and high limits
Either a Rdistance 'model frame' or an Rdistance
'fitted object'. Both are of class "dfunc".
Rdistance 'model frames' are lists containing components
necessary to estimate a distance function, but no estimates.
Rdistance 'model frames' are typically
produced by calls to parseModel.
Rdistance 'fitted objects'
are typically produced by calls to dfuncEstim.
'Fitted objects' are 'model frames'
with additional components such as the parameters estimates,
log likelihood value, convergence information, and the variance-
covariance matrix of the parameters.
A list containing start, low, and high limits for
parameters of the requested likelihood. This list is typically produced
by a call to startLimits.