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_DFP_plot.m
    path of file: ./repos/ExploreASL/External/SPMmodified
    
    the code of the file until where you have to start completion: function spm_DFP_plot(QU,pU)
% plots particles for spm_DFP
% FORMAT spm_DFP_plot(QU,Nt)
% FORMAT spm_DFP_plot(QU,pU)

    
function spm_DFP_plot(QU,pU)
% plots particles for spm_DFP
% FORMAT spm_DFP_plot(QU,Nt)
% FORMAT spm_DFP_plot(QU,pU)
%--------------------------------------------------------------------------
% QU{t}(p).x{d}  - ensemble of hidden states
% QU{t}(p).v{d}  - ensemble of causal states
%__________________________________________________________________________
% Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging

% Karl Friston
% $Id: spm_DFP_plot.m 6540 2015-09-05 10:06:42Z karl $

% defaults for plotting
%--------------------------------------------------------------------------
clf
try
    pX = pU.x{1};
    pV = pU.v{2};
    Nt = length(pX);
catch
    try Nt = pU; catch, Nt = length(QU); end