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_mci_mh.m
    path of file: ./repos/spm/toolbox/mci/inference
    
    the code of the file until where you have to start completion: function [P,L,D] = spm_mci_mh (mcmc,M,U,Y)
% Metropolis Hastings with Gaussian priors and proposals
% FORMAT [P,L,D] = spm_mci_mh (mcmc,M,U,Y)
% 
% mcmc      Optimisation parameters  eg.

    
function [P,L,D] = spm_mci_mh (mcmc,M,U,Y)
% Metropolis Hastings with Gaussian priors and proposals
% FORMAT [P,L,D] = spm_mci_mh (mcmc,M,U,Y)
% 
% mcmc      Optimisation parameters  eg.
%
% .nsamp    number of samples to return 
% .Cprop    proposal density
% .init     initial parameter point
%
% M         Model structure
% U         Inputs
% Y         Data 
%
% P         Posterior samples 
% L         Logjoint history
% D         Diagnostics (D.accept_rate, D.els)
%__________________________________________________________________________

% Will Penny
% Copyright (C) 2015 Wellcome Trust Centre for Neuroimaging

% Compute eigen-parameterisation
M = spm_mci_minit (M);
V  = M.V;

try, init=mcmc.init; catch, init=M.vpE; end