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   sctiks_c ( Convert spacecraft clock string to ticks. ) 

   void sctiks_c ( SpiceInt           sc,
                   ConstSpiceChar   * clkstr,
                   SpiceDouble      * ticks   )


   Convert a spacecraft clock format string to number of "ticks".






   --------  ---  --------------------------------------------------
   sc         I   NAIF spacecraft identification code.
   clkstr     I   Character representation of a spacecraft clock.
   ticks      O   Number of ticks represented by the clock string.


   sc          is the NAIF ID number for the spacecraft whose clock
               string is being converted.

   clkstr      is a character string representing a spacecraft clock
               time, WITHOUT PARTITION NUMBER.

               Using Galileo as an example, the full format 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 the
               following characters: " "  "."  ":"  ","  "-"
               Any number of spaces may separate the components and
               the delimiters. The presence of the RIM component
               is required. Successive components may be omitted, and
               in such cases are assumed to represent zero values.

               Values for the individual components may exceed the
               maximum expected values. For instance, "0:0:0:9" is
               an acceptable Galileo clock string, and will convert
               to the same number of ticks as "0:0:1:1".

               Consecutive delimiters containing no intervening digits
               are treated as if they delimit zero components.

               Trailing zeros should always be included to match the
               length of the counter. For example, a Galileo clock
               count of "25684.90" should not be represented as

               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


   ticks       is the number of ticks represented by the spacecraft
               clock string. A tick is defined to be the smallest
               time increment expressible by the spacecraft clock.

               An analogy may be drawn between a spacecraft clock
               and a standard wall clock, measuring hours, minutes
               and seconds. The number of ticks represented by the
               wall clock string


               would be the number of seconds represented by that

               For example:

                  00:00:10  would convert to 10
                  00:01:00  would convert to 60
                  00:10:00  would convert to 600
                  01:00:00  would convert to 3600
                  01:01:00  would convert to 3660

               See the -Examples section below for examples for
               actual spacecraft clocks.




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

   2)  If any of the extracted clock components cannot be parsed as
       integers, or the string has too many components, or the value
       of one of the components is less than the offset value, then,
       an error is signaled by a routine in the call tree of this

   3)  Invalid spacecraft ID's are not diagnosed.

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

   5)  If the `clkstr' input string has zero length, the error
       SPICE(EMPTYSTRING) is signaled.




   Each spacecraft is assigned a clock type code in the kernel file.
   sctiks_c calls the function SCTYPE to determine this value. If the
   clock type is supported by SPICE, then the SPICELIB routine TIKSnn
   is called to handle the actual conversion from clock format to
   number of ticks. The nn in TIKSnn refers to the spacecraft clock
   type code. Different spacecraft have distinct clock formats but
   can still be of the same clock type.

   The TIKSnn routines are routines to the routines SCLKnn, which
   also contain the ticks-to-clock format conversion routines FMTnn.
   FMTnn is called by the routine scfmt_c, which performs the
   inverse operation to sctiks_c.

   Note the important difference between scencd_c and sctiks_c. scencd_c
   converts a clock string to the number of ticks it represents
   since the beginning of the mission, and so uses partition
   information. sctiks_c just converts to absolute ticks.


   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) sctiks_c is used as part of the process of encoding spacecraft
      clock by scencd_c, though sctiks_c does not process any partition

      Another use of sctiks_c, however, is to convert a clock
      measurement to ticks for use as a tolerance for the CK reader

      In the following example, pointing for a sequence of images from
      the CASSINI Imaging Science Subsystem (ISS) is requested from
      the C-kernel using an array of character spacecraft clock counts
      as input. The clock counts attached to the output are then
      decoded to character and compared with the input strings.

      Use the CK kernel below to load the CASSINI image navigated
      spacecraft pointing and orientation data.


      Use the SCLK kernel below to load the CASSINI spacecraft clock
      time correlation data required for the conversion between
      spacecraft clock string representation and double precision
      encoding of spacecraft clock counts.


      Example code begins here.

         Program sctiks_ex1
      #include <stdio.h>
      #include "SpiceUsr.h"

      int main()
         The instrument we want pointing for is the CASSINI
         spacecraft. The reference frame we want is
         J2000. The spacecraft is CASSINI.

         #define  SC         -82
         #define  INST       -82000
         #define  REF        "J2000"
         #define  CK         "04153_04182ca_ISS.bc"
         #define  SCLK       "cas00071.tsc"
         #define  NPICS      4
         #define  CLKTOL     "1.0"
         #define  MAXLEN     30

         SpiceBoolean       found;

         SpiceChar          sclkin [4][25] = { {"1/1465644279.0"},
                                               {"1/1465644361.0"} };
         SpiceChar          sclkout[25];

         SpiceDouble        tol;
         SpiceDouble        timein;
         SpiceDouble        timeout;
         SpiceDouble        cmat   [3][3];

         SpiceInt           handle;
         SpiceInt           i;

         Load the appropriate files. We need

            1. CK file containing pointing data.
            2. Spacecraft clock kernel file.

         cklpf_c  ( CK,  &handle );
         furnsh_c ( SCLK         );

         Convert the tolerance string to ticks.
         sctiks_c ( SC, CLKTOL, &tol );

         for ( i = 0;  i < NPICS;  i++ )
            scencd_c ( SC,   sclkin[i], &timein );

            ckgp_c   ( INST,  timein,    tol,    REF,
                       cmat,  &timeout,  &found       );

            scdecd_c ( SC, timeout, MAXLEN, sclkout );

            if ( found )
               printf ( "\n"
                        "Input  s/c clock count: %s\n"
                        "Output s/c clock count: %s\n"
                        "Output C-Matrix:          \n"
                        "   %19.16f   %19.16f   %19.16f\n"
                        "   %19.16f   %19.16f   %19.16f\n"
                        "   %19.16f   %19.16f   %19.16f\n",
                        cmat[0][0],  cmat[0][1],  cmat[0][2],
                        cmat[1][0],  cmat[1][1],  cmat[1][2],
                        cmat[2][0],  cmat[2][1],  cmat[2][2] );
               printf ( "\n"
                        "Input  s/c clock count: %s\n"
                        "No pointing found.\n",
                        sclkin[i]                     );

         return ( 0 );

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

      Input  s/c clock count: 1/1465644279.0
      No pointing found.

      Input  s/c clock count: 1/1465644281.0
      Output s/c clock count: 1/1465644281.171
      Output C-Matrix:
         -0.3353514559487096    0.8643744402056108    0.3746948466583409
         -0.9378874268129802   -0.3438519652102230   -0.0461844199616532
          0.0889189272270388   -0.3669095980487626    0.9259971766914239

      Input  s/c clock count: 1/1465644351.0
      Output s/c clock count: 1/1465644351.071
      Output C-Matrix:
         -0.3353809293975862    0.8643636382622295    0.3746933853786226
         -0.9378742920080898   -0.3438898381078248   -0.0461691632640035
          0.0889463017035304   -0.3668995504170804    0.9259985287877129

      Input  s/c clock count: 1/1465644361.0
      No pointing found.

   2) Below are some examples illustrating various clock string inputs
      and the resulting outputs for the Galileo spacecraft. See the
      SCLK required reading for a detailed description of the Galileo
      clock format.

         CLKSTR                TICKS
         ----------------      --------------------
         "0:0:0:1"             1
         "0:0:1"               8
         "0:1"                 80
         "1"                   7280
         "1 0 0 0"             7280
         "1,0,0,0"             7280
         "1:90"                14480
         "1:9"                 8000
         "1:09"                8000
         "0-0-10"              80   |--  Third component is supposed
         "0-1-0"               80   |    to be a mod-10 count.
         "0/1/0"               Error: "/" is not an accepted delimiter.
         "1: 00 : 0 : 1"       7281
         "1:::1"               7281
         ""           Error: Too many components
         ""            Error: The last delimiter signals that
                                      a fifth component will follow.

      The following examples are for the Voyager 2 spacecraft. Note
      that the last component of the Voyager clock has an offset
      value of 1.

         CLKSTR                TICKS
         ----------------      --------------------
          "0.0.001"              0
          "0:0:002"              1
          "0:01"                 800
          "1"                    48000
          "1.0"                  48000
          "1.0.0"                Error: The 3rd component is never 0.
          "0.0:100"              99
          "0-60-1"               48000
          "1-1-1"                48800
          "1-1-2"                48801






   N.J. Bachman        (JPL)
   J. Diaz del Rio     (ODC Space)
   J.M. Lynch          (JPL)
   W.L. Taber          (JPL)
   R.E. Thurman        (JPL)
   E.D. Wright         (JPL)


   -CSPICE Version 1.1.2, 01-NOV-2021 (JDR)

       Edited the header to comply with NAIF standard.

       Created complete example from existing code fragment and added
       input kernels set using PDS archived CASSINI data.

       Added entries #4 and #5 in -Exceptions section.

   -CSPICE Version 1.1.1, 14-AUG-2006 (EDW)

       Replace mention of ldpool_c with furnsh_c.

   -CSPICE Version 1.1.0, 08-FEB-1998 (NJB)

       References to C2F_CreateStr_Sig were removed; code was
       cleaned up accordingly. String checks are now done using
       the macro CHKFSTR.

   -CSPICE Version 1.0.0, 25-OCT-1997 (NJB) (JML) (RET) (WLT)

       Based on SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)


   convert spacecraft_clock string to ticks
Fri Dec 31 18:41:12 2021