function OUT = prcout_(IN,flag)
% PRCOUT_   - Process Eqpac data from READOUT_

% NOTE: The time field in the input structure X must be named TIME_TAG and the
% structure must also have the first field named Filename.

% Brian Schlining
% 13 Jan 1998

if nargin < 2
   flag = 0;
end

%=========================================================================
% Need the date, down to the Minute, to find the ~15 1 sec readings taken
% every 15 minutes
%=========================================================================
[Year, Month, Day, Hour, Minute, Second] = datevec(IN.TIME_TAG);
OUT.Filename = IN.Filename;            % hang onto the filename
Fields       = fieldnames(IN);         % Get all the field names
NumOfFields  = length(Fields);         % Count the number of fields
NumOfPoints  = length(IN.TIME_TAG);    % Count the number of readings

n = 1;                                 % Counter for the start of each 15 minute data set
m = 1;                                 % The position we're writing the data to

fprintf(1,'\n(PRCOUT_)')
OK = 1;                                
while OK
   
   % Preallocate LOTS of memory on the first run through the infinite while loop. If
   % this isn't done the program is REALLY SLOW. Here we're allocating a structure 
   % the same size as IN and filling it with NaN's
   if m == 1
      for i = 2:NumOfFields
         OUT = setfield(OUT,{1},Fields{i},{1:NumOfPoints,1},NaN);
      end
   end
   
   switch flag
   case 0   % average the data from every 15 minutes
      
      % Find all data points that occur during any given minute
      j = find(Year == Year(n) & Month == Month(n) & Day == Day(n) & ...
         Hour == Hour(n) & Minute == Minute(n));
      
      % Get the data that occurs during each minute, take its average and then 
      % write it out to the new structure, OUT.
      for i = 2:NumOfFields
         f   = getfield(IN,Fields{i},{j});
         f   = mean(f);
         OUT = setfield(OUT,Fields{i},{m,1},f);
      end
      
      n = n + length(j);   % position for the next set of replicates
      m = m + 1;           % position index for OUT
      
   case 1   % Create a daily average for data between 10am and 2pm
           
      % Find all data points between 10:00 and 14:00 for each day
      % At some point we'll need to flag this if not enough data
      % points occur during this period
      j = find(Year == Year(n) & Month == Month(n) & Day == Day(n) & ...
         Hour >= 10 & Hour <= 14); 
      %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
      %Almost: need to see if the time's in the out files are GMT or local
      % and readjust Hour accordingly
      %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
      
      k = find(Year == Year(n) & Month == Month(n) & Day == Day(n)); 
      
      
      
      if ~isempty(j)
         % Get the data that occurs during each minute, take its average and then 
         % write it out to the new structure, OUT.
         for i = 2:NumOfFields
            f   = getfield(IN,Fields{i},{j});
            f   = mean(f);
            OUT = setfield(OUT,Fields{i},{m,1},f);
         end
         n = n + length(k);
         m = m + 1;
         fprintf(1, 'Line %6i: ~isempty(j)\n',n)
      elseif isempty(j) & ~isempty(k)
         n = n + length(k)';
         fprintf(1, 'Line %6i: isempty(j) & ~isempty(k)\n',n)
      else
         n = n + 1;
         fprintf(1,'Line: %6i: isempty(j) & isempty(k)\n',n)
      end
      
      
   end
   
   
   if ~rem(m,200)
      fprintf(1,'.')
   end
   
   
   % Exit the loop when the end of the data is reached. 
   if n > NumOfPoints
      fprintf(1,'\n')
      % Remove all the trailing NaN's before returning OUT
      NotNaN = find(~isnan(OUT.TIME_TAG));
      for i = 2:NumOfFields
         f = getfield(OUT,Fields{i},{NotNaN});
         OUT = setfield(OUT,Fields{i},f);
      end
      
      return      % Exit 
      
   end
   
   
end