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: spm_dcm_HMM_plot.m
    path of file: ./repos/spm12
    
    the code of the file until where you have to start completion: function spm_dcm_HMM_plot(HMM,s)
% FORMAT spm_dcm_HMM_plot(HMM,s)
% subroutine for potting the results of a hidden Markov model of state
% transitions in the DCM
% 
% HMM(s)
%     HMM(s).X  - posterior expectation of hidden states
%     HMM(s).qB - posterior expectation of HMM parameters
%     HMM(s).qb - and Dirichlet concentration parameters
%     HMM(s).qP - posterior expectation of PEB parameters
%     HMM(s).qC - posterior covariances of PEB parameters
%     HMM(s).iP - indices of DCM parameters
%     HMM(s).Ep - posterior expectation of DCM parameters
%     HMM(s).Cp - posterior covariances of DCM parameters
%     HMM(s).L  - free energy components
%     HMM(s).F  - total free energy (model evidence)
%
% s  -  index of HMM structure (number of hidden states)

    
function spm_dcm_HMM_plot(HMM,s)
% FORMAT spm_dcm_HMM_plot(HMM,s)
% subroutine for potting the results of a hidden Markov model of state
% transitions in the DCM
% 
% HMM(s)
%     HMM(s).X  - posterior expectation of hidden states
%     HMM(s).qB - posterior expectation of HMM parameters
%     HMM(s).qb - and Dirichlet concentration parameters
%     HMM(s).qP - posterior expectation of PEB parameters
%     HMM(s).qC - posterior covariances of PEB parameters
%     HMM(s).iP - indices of DCM parameters
%     HMM(s).Ep - posterior expectation of DCM parameters
%     HMM(s).Cp - posterior covariances of DCM parameters
%     HMM(s).L  - free energy components
%     HMM(s).F  - total free energy (model evidence)
%
% s  -  index of HMM structure (number of hidden states)
%       [default: HMM(end)]
%__________________________________________________________________________
% Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging

% Karl Friston
% $Id: spm_dcm_HMM_plot.m 7580 2019-05-01 12:48:04Z karl $

%  preliminaries: get the hidden Markov model to report
%--------------------------------------------------------------------------
spm_figure('Getwin','HMM'); clf
if nargin < 2, s = length(HMM); end