[err,err_msg]=CefSplitter(filename,datadir);

%------------------------------------------------------------------------%
%  Program   : CEF 2.0 SPLITTER                                          %
%------------------------------------------------------------------------%
%  Purpose   : To split a measurement data file in the ITU recommended   %
%              "Common Exchange Format V2.0" that contains N frequency   %
%              scans into N independent files of the same CEF 2.0 format.%
%                                                                        %
%              Each file now contains one frequency scan and the header  %
%              information is adapted accordingly.                       %
%                                                                        %
%------------------------------------------------------------------------%
%  MatLab code version:  7.1                                             %
%------------------------------------------------------------------------%
%  External functions used: Cef2Mat (v1.06)                              %
%------------------------------------------------------------------------%
%  Creation / modification history:                                      %
%  2008-08-25 - v1.00 - B.A.Witvliet - creation                          %
%------------------------------------------------------------------------%
%  Conventions:                                                          %
%  - Every new author adds to the modification history, but does never   %
%    erase names of earlier contributors.                                %
%  - Arrays start with a capitol letter, single variables and single     %
%    variables don't.                                                    %
%  - Main program names are all capitals, functions names only start     %
%    with a capital.                                                     %
%  - Subprograms are always functions, not scripts.                      %
%  - Global variables are avoided.                                       %
%------------------------------------------------------------------------%

function [err,err_msg]=CefSplitter(filename,datadir); 


% ------------------
% ERROR MESSAGES
% ------------------
% err  err_msg
% 0   OK
% 0   Single scan file, no splitting performed
% 1   File retrieval error (No such file)
% 2   No CEF 2.0 file
% 3   CEF file header could not be read
% 4   CEF file body could not be read
% 5   Filename should be specified without extension


% ----------------------------------
% LOAD FILE INTO WORKSPACE
% ----------------------------------
[Header,Data,err,err_msg] = Cef2Mat_v1_06(filename,datadir); 


% ----------------------------------
% HOW MANY SCANS IN FILE?
% ----------------------------------
n=size(Data.Level,3);
if n==1
    err=0; err_msg='Single scan CEF 2.0 file, no splitting performed';
    return;
end;


% ------------
% REDUCE TO N SINGLE SCAN MAT-FILES
% ------------

% -  Retain the original multiscan data -
Header0=Header;
Data0=Data;

% - Go through all individual scans one by one -
for scannr=1:n
    
    % - Reduce header to a single scan header
    Header.FreqStart      =Header0.FreqStart(scannr); 
    Header.FreqStop       =Header0.FreqStop(scannr); 
    Header.AntennaType    =Header0.AntennaType(scannr); 
    Header.FilterBandwidth=Header0.FilterBandwidth(scannr); 
    Header.DataPoints     =Header0.DataPoints(scannr); 
    Header.Multiscan      ='N'; 
    
    % - Reduce data set to a single scan
    Data.Level=Data0.Level(:,:,scannr);
    
    % - Create filename with full path info - plus a scan number
    fullname=[datadir '/' filename '_' num2str(scannr) '.mat'];

    % - Save the single scan file -
    save(fullname,'Header','Data');

end;