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Abstract
I/O
Examples
Particulars
Required Reading
Version
Index_Entries

Abstract


   CSPICE_ET2UTC converts an input time from ephemeris seconds
   past J2000 to Calendar, Day-of-Year, or Julian Date format, UTC.

I/O


   Given:

      et       the double precision scalar or 1xN array of ephemeris
               time expressed as ephemeris seconds past J2000

      format   the scalar string format flag describing the output time
               string, it may be any of the following:

                  'C'      Calendar format, UTC

                  'D'      Day-of-Year format, UTC

                  'J'      Julian Date format, UTC

                  'ISOC'   ISO Calendar format, UTC

                  'ISOD'   ISO Day-of-Year format, UTC

      prec     the scalar integer number of decimal places of precision to
               which fractional seconds (for Calendar and Day-of-Year
               formats) or days (for Julian Date format) are to be
               computed

   the call:

      utcstr = cspice_et2utc( et, format, prec )

   returns:

      utcstr    the scalar string or NXM character array of output time
                strings equivalent to the input epoch 'et', in the specified
                'format'

                'utcstr' returns with the same vectorization measure (N)
                as 'et'.

Examples


   Any numerical results shown for this example may differ between
   platforms as the results depend on the SPICE kernels used as input
   and the machine specific arithmetic implementation.

      %
      % Define an arbitrary ephemeris time.
      %
      et     = -527644192.5403653;
      format = 'J';
      prec   = 6;
      SIZE   = 5;

      %
      % Load a leapseconds kernel.
      %
      cspice_furnsh( 'standard.tm' )

      %
      % Convert the ephemeris time to Julian Date
      % 'format'. Define precision to 6 decimal
      % places.
      %
      utcstr = cspice_et2utc( et, format, prec );
      disp( 'Scalar:' )

      txt = sprintf( 'ET              : %12.4f', et );
      disp(txt)

      txt = sprintf( 'Converted output: %s', utcstr );
      disp( txt )

      %
      % Create an array of ephemeris times beginning
      % at -527644192.5403653 with graduations of 10000.0
      % ephemeris seconds.
      %
      et     = [0:(SIZE-1)]*10000. -527644192.5403653;
      format = 'C';

      %
      % Convert the array of ephemeris times 'et' to an
      % array of UTC strings, 'utcstr', in calendar
      % 'format'.
      %
      utcstr= cspice_et2utc( et, format, prec );

      disp( ' ' )
      disp( 'Vector:' )

      for n=1:SIZE

         txt = sprintf( 'ET              : %12.4f', et(n) );
         disp( txt )

         txt = sprintf( 'Converted output: %s', utcstr(n,:) );
         disp( txt )

         disp(' ' )

      end

      %
      % It's always good form to unload kernels after use,
      % particularly in MATLAB due to data persistence.
      %
      cspice_kclear

   MATLAB outputs:

      Scalar:
      ET              : -527644192.5404
      Converted output: JD 2445438.006415

      Vector:
      ET              : -527644192.5404
      Converted output: 1983 APR 13 12:09:14.274000

      ET              : -527634192.5404
      Converted output: 1983 APR 13 14:55:54.274001

      ET              : -527624192.5404
      Converted output: 1983 APR 13 17:42:34.274001

      ET              : -527614192.5404
      Converted output: 1983 APR 13 20:29:14.274002

      ET              : -527604192.5404
      Converted output: 1983 APR 13 23:15:54.274002

Particulars


   Use of this routine requires a loaded leapseconds kernel.

Required Reading


   For important details concerning this module's function, please refer to
   the CSPICE routine et2utc_c.

   MICE.REQ
   TIME.REQ

Version


   -Mice Version 1.0.0, 22-NOV-2005, EDW (JPL)

Index_Entries


   ephemeris time to utc


Tue Jul 15 14:36:37 2014