1 function app = getExcelInstance
 2 %   Copyright 2015 The MathWorks, Inc.
 3 
 4      persistent excelApplication;
 5     if isempty(excelApplication) || ~isactive || excelApplication.Visible
 6         % If Excel is not available, this will throw an exception.  If
 7         % Excel has been made visible, we assume the user opened the
 8         % worksheet outside MATLAB using the same Excel process, and so we
 9         % should start a new process.
10         excelApplication = actxserver('Excel.Application');
11     end
12     app = excelApplication;
13     
14     function tf = isactive
15         % Try accessing a readonly property of the COM server to see if it is
16         % active.
17         try
18             get(excelApplication, 'Version');
19             tf = true;
20         catch
21             excelApplication.delete;
22             excelApplication = [];
23             tf = false;
24         end
25     end
26 end