function [time,wtrTemp] = airTemp2inflowTemp(inFileName,outFileName,ndayAvg)

% function [time,wtrTemp] = airTemp2inflowTemp(inFileName,outFileName,ndayAvg)
%
% funcion to read ELCOM input AIR_TEMP bc file and convert to WATER_TMP by
% averaging over a certain time period
%
% Inputs:
%		inFileName   :  bc file containig air temp data
%		outFileName  :  name of bc file to create
%   ndayAvg      :  number of days to average ove (optional - default is 4)
% Outputs
%		time      : time column in CWR Format
%		wtrTemp  : water temperature column
%
% Uses:
%		CWRdate2matlab.m
%		readELCOMinputFile.m
%		readELCOMinputFileHeader.m
%		line2strs.m
%
% Written by C. Dallimore 27 July 04

% Set averaging length
if nargin == 3
elseif nargin == 2
	ndayAvg = 4;
else
	disp('Incorrect number of arguments to airTemp2inflowTemp')
	ierr =1;
	time = [];
	wtrTemp = [];
	return
end

% Read file
[data,data_type,bcset_no,n_data,file_type]=readELCOMinputFile(inFileName);

% Check ile is normal bc file
if (~strcmp(file_type,'BC'))
	error ('File is not BC File')
	return
end

cwrTimeIn = data(:,1);
timeIn = CWRdate2matlab(cwrTimeIn);

% get air temp column
ind=strmatch('AIR_TEMP',data_type,'exact');
if (isempty(ind))
	error ('File does not contain air temperature')
	return
else
	airTemp= data(:,ind);
end

ndays = floor(max(timeIn))-floor(min(timeIn))+1;
day0 = floor(min(timeIn));

timeOut = [];
for i=1:ndays
	timeOut(i) = day0+i;
	pts = find((timeIn < timeOut(i)) & (timeIn > timeOut(i)-ndayAvg));
	wtrTemp(i) = mean(airTemp(pts));
end

% Set minimum to 3o
pts = find(wtrTemp<3);
wtrTemp(pts) = 3;

% Convert back to CWR Date
time = matlab2CWRdate(timeOut);
% Write to file
fout = fopen(outFileName,'w');
fprintf(fout,'! ------------------------------------------------------------- !\n');
fprintf(fout,'! Matlab generated inflow temp file                             !\n');
fprintf(fout,['! Average of ',int2str(ndayAvg),' days of air temp data                            !\n']);
fprintf(fout,'! ------------------------------------------------------------- !\n');
fprintf(fout,'1 data sets\n');
fprintf(fout,'0 seconds between data\n');
fprintf(fout,'     0     	 need to put bc\n');
fprintf(fout,'   TIME        WTR_TEMP\n');
tmpData = [time; wtrTemp];
fprintf(fout,'%12.3f %5.1f\n',tmpData);
fclose (fout);