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_phase_data.m
    path of file: ./repos/bspm/thirdparty/spm12/toolbox/dcm_meeg
    
    the code of the file until where you have to start completion: function DCM = spm_dcm_phase_data(DCM)
% Get data for DCM for phase coupling
% FORMAT [DCM] = spm_dcm_phase_data(DCM)
%
% DCM    -  DCM structure
%
% Requires/requests:

    
function DCM = spm_dcm_phase_data(DCM)
% Get data for DCM for phase coupling
% FORMAT [DCM] = spm_dcm_phase_data(DCM)
%
% DCM    -  DCM structure
%
% Requires/requests:
%
%    DCM.xY.Dfile   - M/EEG data filename
%    DCM.Lpos       - Matrix of source locations
%    DCM.options.trials - To select particular trials (otherwise all selected)
%    DCM.options.Fdcm   - to select frequency window for analysis
%    DCM.options.Hdcm - to select time window for filtering and Hilbert transform
%                       default=[beginning of epoch, end