all = vector of all unfixed params var derivative is a vector of 1 and 0, 1 means derivative of parameter is taken w.r.t. variance otherwise w.r.t. sd If params is supplied then the parameter is taken from this vector instead of poped.db
Value
A list with the  parameters.  All unfixed parameters are also
  returned in the "all output with the specified order
  (bpop,d,covd,docc,covdocc,sigma,covsigma). var_derivative  is a
  vector of 1's or 0's, 1 means derivative of parameter is taken with respect
  to the variance otherwise with respect to standard deviation.
