You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: VBA_FreeEnergy.m
    path of file: ./repos/PsPM/src/ext/VBA
    
    the code of the file until where you have to start completion: function [F] = VBA_FreeEnergy(posterior,suffStat,options)
% computes free energy of the sDCM generative model
% function [F] = VBA_FreeEnergy(posterior,suffStat,options)
% This function evaluates the free energy associated with the nonlinear
% state-space model inverted by the main inversion routine
% VBA_NLStateSpaceModel.m.
% IN:
%   - posterior: a structure containing the natural parameters of the
%   marginal posterior pdf of the unknown variables of the model
%   - suffStat: a structure containing pre-calculated (sufficient
%   statistics) quantities associated required for the computation of the
%   free energy (such as derivatives of the evolution/observation functions
%   evaluated at the current mode)

    
function [F] = VBA_FreeEnergy(posterior,suffStat,options)
% computes free energy of the sDCM generative model
% function [F] = VBA_FreeEnergy(posterior,suffStat,options)
% This function evaluates the free energy associated with the nonlinear
% state-space model inverted by the main inversion routine
% VBA_NLStateSpaceModel.m.
% IN:
%   - posterior: a structure containing the natural parameters of the
%   marginal posterior pdf of the unknown variables of the model
%   - suffStat: a structure containing pre-calculated (sufficient
%   statistics) quantities associated required for the computation of the
%   free energy (such as derivatives of the evolution/observation functions
%   evaluated at the current mode)
%   - options: a structure variable containing optional parameters (such as
%   the priors structure)
% OUT:
%   - F: the free energy under the local Laplace approximation


if options.UNL % to be rationalized when UNL is extend