clear all;

a1 = ao(plist('waveform', 'sine wave', 'f', 1, 'phi', 0, 'nsecs', 10, 'fs', 100));
a2 = ao(plist('waveform', 'sine wave', 'f', 1, 'phi', 0, 'nsecs', 10, 'fs', 100));
a3 = a1 + a2;

c1 = a3.hist;

xmlfile = 'history.xml';
save(c1, xmlfile);

% load
c2 = history(xmlfile);

if c1 ~= c2(1)
  error('### history are not the same')
end

     