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: anonymize_dicm.m
    path of file: ./repos/bspm/thirdparty/dicm2nii
    
    the code of the file until where you have to start completion: function anonymize_dicm(src, rst, subID)
% Replace PatientName in dicom header with an ID without altering ANYTHING else.
% 
%  anonymize_dicm('sourceFolder', 'anonymizedFolder', 3) % 'sub003' as ID
% 
% All three input argument are optional:
%  1. A dicom file name or a folder containing dicom files to anonymize.
%  2. A file name (single source file) or a folder to save the result file(s).
%  3. Starting subject ID to replace PatientName, default 'sub001'. This can be
%     numeric, like 3 which will be converted into 'sub003', or full string like
%     'subj_04' specifying both the prefix and starting ID number.
% 

    
function anonymize_dicm(src, rst, subID)
% Replace PatientName in dicom header with an ID without altering ANYTHING else.
% 
%  anonymize_dicm('sourceFolder', 'anonymizedFolder', 3) % 'sub003' as ID
% 
% All three input argument are optional:
%  1. A dicom file name or a folder containing dicom files to anonymize.
%  2. A file name (single source file) or a folder to save the result file(s).
%  3. Starting subject ID to replace PatientName, default 'sub001'. This can be
%     numeric, like 3 which will be converted into 'sub003', or full string like
%     'subj_04' specifying both the prefix and starting ID number.
% 
% To avoid subject name confusion, this function replaces PatientName with an ID
% (third input argument). In case of multiple patients, the ID will be increased
% by 1 for each patient, and a file 'subjIDs_PatientNames.mat' will be saved
% into the source folder to indicate the correspondence between the original
% PatientName and assigned subject IDs.
% 
% See also DICM_HDR, SORT_DICM, RENAME_DICM, DICM2NII

% 161226 Wrote it (xiangrui.li@gmail.com)
% 170103 Take care of confusion of multi-subjects; safer by using dicm tag.

% 3rd input can be either a number, or string like 'subj_001'
if nargin<3 || isempty(subID), subID = 'sub001'; end
if isnumeric(subID), subID = sprintf('sub%03g', subID); end