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   scfmt_c ( Convert SCLK "ticks" to character clock format ) 

   void scfmt_c  ( SpiceInt            sc,
                   SpiceDouble         ticks,
                   SpiceInt            clklen,
                   SpiceChar         * clkstr )


   Convert encoded spacecraft clock ticks to character clock format.






   --------  ---  --------------------------------------------------
   sc         I   NAIF spacecraft identification code.
   ticks      I   Spacecraft clock count encoded representation.
   clklen     I   Maximum length of output string `clkstr'.
   clkstr     O   Character representation of a clock count.


   sc          is the NAIF ID number for the spacecraft whose clock's
               time is being decoded.

   ticks       is the double precision encoding of a clock time in
               units of ticks. Partition information is not reflected
               in this value.

               An analogy may be drawn between a spacecraft clock and
               a standard wall clock. The number of ticks
               corresponding to the wall clock string


               would be the number of seconds represented by that

               For example,

                  Clock string    Number of ticks
                  ------------    ---------------
                    00:00:10             10
                    00:01:00             60
                    00:10:00            600
                    01:00:00           3600
                    01:01:00           3660

               If `ticks' contains a fractional part the result is the
               same as if `ticks' had been rounded to the nearest whole

               See the -Examples section below for examples of
               actual spacecraft clock conversions.

   clklen      is the maximum allowed length of the output string
               `clkstr'. This length must be large enough to hold the
               output string plus the null-terminator character. If the
               output string is expected to have N characters, `clklen'
               should be at least N+1.


   clkstr      is the spacecraft clock character string
               corresponding to `ticks'. Partition information is
               not included in `clkstr'.

               Using Galileo as an example, the full format clock
               string is


               where z is a mod-8 counter (values 0-7) which
               increments approximately once every 8 1/3 ms., y is a
               mod-10 counter (values 0-9) which increments once
               every time z turns over, i.e., approximately once every
               66 2/3 ms., xx is a mod-91 (values 0-90) counter
               which increments once every time y turns over, i.e.,
               once every 2/3 seconds. wwwwwwww is the Real-Time Image
               Count (RIM), which increments once every time xx turns
               over, i.e., once every 60 2/3 seconds. The roll-over
               expression for the RIM is 16777215, which corresponds
               to approximately 32 years.

               wwwwwwww, xx, y, and z are referred to interchangeably
               as the fields or components of the spacecraft clock.
               SCLK components may be separated by any of these five
               characters: " "  ":"  ","  "-"  "."
               The delimiter used is determined by a kernel pool
               variable and can be adjusted by the user.

               Some spacecraft clock components have offset, or
               starting, values different from zero. For example,
               with an offset value of 1, a mod 20 counter would
               cycle from 1 to 20 instead of from 0 to 19.

               See the SCLK required reading for a detailed
               description of the Voyager and Mars Observer clock




   1)  If the data type for the spacecraft is not supported, the
       error SPICE(NOTSUPPORTED) is signaled by a routine in the call
       tree of this routine.

   2)  If the value for `ticks' is negative, an error is signaled
       by a routine in the call tree of this routine.

   3)  If the SCLK kernel file does not contain data for the
       spacecraft specified by `sc', an error is signaled by a routine
       in the call tree of this routine.

   4)  If the declared length of `clkstr' is not large enough to
       contain the output clock string, an error is signaled by a
       routine in the call tree of this routine.

   5)  If the `clkstr' output string pointer is null, the error
       SPICE(NULLPOINTER) is signaled.

   6)  If the `clkstr' output string has length less than two
       characters, the error SPICE(STRINGTOOSHORT) is signaled, since
       the output string is too short to contain one character of
       output data plus a null terminator.




   The routine sctiks_c performs the inverse operation to scfmt_c,
   converting from clock format to number of ticks.

   Note the important difference between scfmt_c and scdecd_c. scdecd_c
   converts some number of ticks since the spacecraft clock start
   time to a character string which includes a partition number.
   scfmt_c, which is called by scdecd_c, does not make use of partition


   The numerical results shown for these examples may differ across
   platforms. The results depend on the SPICE kernels used as input,
   the compiler and supporting libraries, and the machine specific
   arithmetic implementation.

   1) The following code example finds partition start and stop
      times for the Stardust spacecraft from a spacecraft clock
      kernel file. Since those times are always returned in units
      of ticks, the program uses scfmt_c to print the times in
      Stardust clock format.

      Use the SCLK kernel below to load the Stardust time
      correlation data and spacecraft clock partition information.


      Example code begins here.

         Program scfmt_ex1
      #include <stdio.h>
      #include "SpiceUsr.h"

      int main()
         Local parameters.
         #define                CLKLEN   31
         #define                MXPART   9999

         Local variables.
         SpiceChar              start  [ CLKLEN ];
         SpiceChar              stop   [ CLKLEN ];

         SpiceDouble            pstart [ MXPART ];
         SpiceDouble            pstop  [ MXPART ];

         SpiceInt               sc;
         SpiceInt               i;
         SpiceInt               nparts;

         Assign the value for the Stardust spacecraft ID.
         sc = -29;

         Load the SCLK file.
         furnsh_c ( "sdu_sclkscet_00074.tsc" );

         Retrieve the arrays for `pstart' and `pstop' and the
         number of partitions within the SCLK.
         scpart_c ( sc, &nparts, pstart, pstop );

         Loop over each array value.
         for ( i = 0;  i < nparts;  i++ )
            scfmt_c ( sc, pstart[ i ], CLKLEN, start );
            scfmt_c ( sc, pstop [ i ], CLKLEN, stop  );

            printf ( "\n"
                     "Partition: %d\n"
                     "   Start : %s\n"
                     "   Stop  : %s\n",
                      stop                );

         return ( 0 );

      When this program was executed on a Mac/Intel/cc/64-bit
      platform, the output was:

      Partition: 0
         Start : 0000000000.000
         Stop  : 0602741011.080

      Partition: 1
         Start : 0602741014.217
         Stop  : 0605660648.173

      Partition: 2
         Start : 0605660649.000
         Stop  : 0631375256.224

      Partition: 3
         Start : 0631375257.000
         Stop  : 0633545577.218

      Partition: 4
         Start : 0633545578.000
         Stop  : 0644853954.043

      Partition: 5
         Start : 0644853954.000
         Stop  : 0655316480.089

      Partition: 6
         Start : 0655316480.000
         Stop  : 0660405279.066

      Partition: 7
         Start : 0660405279.000
         Stop  : 0670256568.229

      Partition: 8
         Start : 0670256569.000
         Stop  : 0674564039.091

      Partition: 9
         Start : 0674564040.000
         Stop  : 4294537252.255

   2) Below are some examples illustrating various input numbers of
      ticks and the resulting clock string outputs for the Galileo

         ticks                clkstr
         ----------------     --------------------
         -1                   Error: Ticks must be a positive number
         0                    "00000000:00:0:0"
         1                    "00000000:00:0:1"
         1.3                  "00000000:00:0:1"
         1.5                  "00000000:00:0:2"
         2                    "00000000:00:0:2"
         7                    "00000000:00:0:7"
         8                    "00000000:00:1:0"
         80                   "00000000:01:0:0"
         88                   "00000000:01:1:0"
         7279                 "00000000:90:9:7"
         7280                 "00000001:00:0:0"
         1234567890           "00169583:45:6:2"

      The following examples are for the Voyager 2 spacecraft.
      Note that the third component of the Voyager clock has an
      offset value of one.

         ticks                clkstr
         ----------------     --------------------
         -1                   Error: Ticks must be a positive number
         0                    "00000:00:001"
         1                    "00000:00:002"
         1.3                  "00000:00:002"
         1.5                  "00000:00:003"
         2                    "00000:00:003"
         799                  "00000:00:800"
         800                  "00000:01:001"
         47999                "00000:59:800"
         48000                "00001:00:001"
         3145727999           "65535:59:800"






   N.J. Bachman        (JPL)
   J. Diaz del Rio     (ODC Space)
   E.D. Wright         (JPL)


   -CSPICE Version 1.2.0, 10-AUG-2021 (JDR)

       Changed the input argument name "lenout" to "clklen" for consistency
       with other routines.

       Edited the header to comply with NAIF standard. Added
       reference to required SCLK and created complete example from
       existing code fragment using Stardust PDS archived data.

   -CSPICE Version 1.1.4, 11-FEB-2008 (NJB)

       Header example was updated to reflect current
       MXPART value of 9999.

   -CSPICE Version 1.1.3, 14-AUG-2006 (EDW)

       Replace mention of ldpool_c with furnsh_c.

   -CSPICE Version 1.1.2, 01-OCT-2003 (EDW)

       Added description of the 'lenout' input in the
       -Detailed_Input section.

   -CSPICE Version 1.1.1, 26-MAR-2003 (NJB)

       Fixed description of exception (6):  replaced "lenout-1"
       with "lenout."

   -CSPICE Version 1.1.0, 09-FEB-1998 (NJB)

       Re-implemented routine without dynamically allocated, temporary
       strings. Updated the -Exceptions header section.

   -CSPICE Version 1.0.0, 25-OCT-1997 (NJB)

       Based on SPICELIB Version 1.0.1, 17-APR-1992 (JML) (WLT)


   convert spacecraft_clock ticks to character clock format
Fri Dec 31 18:41:11 2021