code: def summarise_events(self):
          
          all_dates = []
          d_command = self._count_by_date(self.command_file, all_dates)
          d_result  = self._count_by_date(self.result_file,  all_dates)
          d_process = self._count_by_date(self.process_file, all_dates)
          d_source  = self._count_by_date(self.source_file,  all_dates)
  
          with open(self.log_sum, "w") as sum_file:
              sum_file.write('date,command,result,process,source\n')
              for dte in sorted(set(all_dates)):
                  sum_file.write(dte + ',')
                  if dte in d_command:
                      sum_file.write(str(d_command[dte]) + ',')
                  else:
                      sum_file.write('0,')
                  if dte in d_result:
                      sum_file.write(str(d_result[dte]) + ',')
                  else:
                      sum_file.write('0,')
                  if dte in d_process:
                      sum_file.write(str(d_process[dte]) + ',')
                  else:
                      sum_file.write('0,')
                  if dte in d_source:
                      sum_file.write(str(d_source[dte]) + '\n')
                  else:
                      sum_file.write('0\n')
docs: takes the logfiles and produces an event summary matrix
              date        command result  process source
              20140421    9       40      178     9
              20140423    0       0       6       0
              20140424    19      1       47      19
              20140425    24      0       117     24
              20140426    16      0       83      16
              20140427    1       0       6       1
              20140429    0       0       0       4