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−% DATENUM Converts a time object into MATLAB serial date representation
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−% DESCRIPTION: Converts a time object into MATLAB serial date number.  A serial
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−% date number of 1 corresponds to Jan-01-0000.  The year 0000 is merely a
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−% reference point and is not intended to be interpreted as a real year.
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−% 
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−% NOTE: time objects formatting routines use the timezone specified in the LTPDA
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−% toolbox preferences, while MATLAB time routines always work in the local time
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−% zone, as specified by the operating system.  This conversion routine is built
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−% so that the time string representation obtained by time.format() and the one
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−% obtained from datestr(datenum(time)) are equivalent:
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−%
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−%   >> t1 = time();
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−%   >> datestr(datenum(t1)) === t1.format('dd-mmm-yyyy HH:MM:SS')
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−%
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−% However, except in the cases where the timezone is set to UTC in the LTPDA
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−% toolbox preferences, this implies that:
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−%
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−%   >> datenum(time()) ~= now()
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−%
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−% VERSION: $Id: datenum.m,v 1.2 2010/07/29 18:07:55 nicolodi Exp $
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−%
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−
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−function num = datenum(obj)
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−  
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−  % number of seconds since 1970-01-01 00:00:00.000 UTC
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−  num = double(obj);
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−  
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−  % take care of timezone offset
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−  num = num + time.timezone.getOffset(num * 1000)/1000;
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−  
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−  % divide by 60*60*24 to convert into days and add offset computed in local time
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−  num = num / 86400 + datenummx(1970,01,01,00,00,00);
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−
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−  % NOTE: the MEX function datenummx() is used instead of the datenum() MATLAB
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−  % function to save time of the expensive input arguments checks performed by
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−  % the later
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−
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−end
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−