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_MDP_VB_LFP.m
    path of file: ./repos/bspm/thirdparty/spm12/toolbox/DEM
    
    the code of the file until where you have to start completion: function [u,v] = spm_MDP_VB_LFP(MDP,UNITS,FACTOR)

    
function [u,v] = spm_MDP_VB_LFP(MDP,UNITS,FACTOR)
% auxiliary routine for plotting simulated electrophysiological responses
% FORMAT [u,v] = spm_MDP_VB_LFP(MDP,UNITS,FACTOR)
%
% u - selected unit rate of change of firing (simulated voltage)
% v - selected unit responses {number of trials, number of units}
%
% MDP - structure (see spm_MDP_VB_X.m)
%__________________________________________________________________________
% Copyright (C) 2005 Wellcome Trust Centre for Neuroimaging
 
% Karl Friston
% $Id: spm_MDP_VB_LFP.m 6978 2017-01-03 10:42:09Z karl $
 
 
% defaults
%==========================================================================
try, f = FACTOR; catch, f = 1;      end