Procedure

   dafus_c ( DAF, unpack summary ) 

   void dafus_c ( ConstSpiceDouble   sum [],
                  SpiceInt           nd,
                  SpiceInt           ni,
                  SpiceDouble        dc  [],
                  SpiceInt           ic  []  )

Abstract

   Unpack an array summary into its double precision and integer
   components.

Required_Reading

   DAF

Keywords

   CONVERSION
   FILES

Brief_I/O

   VARIABLE  I/O  DESCRIPTION
   --------  ---  --------------------------------------------------
   sum        I   Array summary.
   nd         I   Number of double precision components.
   ni         I   Number of integer components.
   dc         O   Double precision components.
   ic         O   Integer components.

Detailed_Input

   sum         is an array summary. This identifies the contents and
               location of a single array within a DAF.

   nd          is the number of double precision components in
               the summary.

   ni          is the number of integer components in the summary.

Detailed_Output

   dc          are the double precision components of the summary.

   ic          are the integer components of the summary.

Parameters

   None.

Exceptions

   Error free.

   1)  If `nd' is zero or negative, no double precision components
       are returned.

   2)  If `ni' is zero or negative, no integer components are returned.

   3)  If the total size of the summary is greater than 125 double
       precision words, some components may not be returned.

Files

   None.

Particulars

   The components of array summaries are packed into double
   precision arrays for reasons outlined in [1]. Two routines,
   DAFPS (pack summary) and dafus_c (unpack summary) are provided
   for packing and unpacking summaries.

   The total size of the summary is

           (ni - 1)
      nd + -------- + 1
               2

   double precision words (where nd, ni are nonnegative).

Examples

   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) In the following code fragment, dafopr_c is used to open a file,
      which is then searched for DAFs containing data for a particular
      object. dafus_c is used to unpack the summaries so the
      applicability of the segments can be determined.


         #include "SpiceUsr.h"
              .
              .
              .
         dafopr_c ( fname, &handle );
         dafbfs_c ( handle );

         daffna_c ( &found );

         while ( found )
         {
            dafgs_c ( sum );
            dafus_c ( sum, ND, NI, dc, ic );

            if ( ic[0] == target_object )
            {
               .
               .
               .
            }

            daffna_c ( &found );
         }

   2) Create a simple program to output the double precision and integer
      values stored in an SPK's segments' descriptors. This function
      opens a DAF for read, performs a forwards search for the DAF
      arrays, prints the segment descriptor for each array found, then
      closes the DAF.

      Use the SPK kernel below as input DAF file for the program.

         de421.bsp


      Example code begins here.


      /.
         Program dafus_ex1
      ./
      #include <stdio.h>
      #include "SpiceUsr.h"

      int main()
         {

         /.
         Local constants
         ./

         /.
         Define the summary parameters appropriate
         for an SPK file.
         ./

         #define ND              2
         #define NI              6
         #define MAXSUM          125

         SpiceInt                ic  [ NI ];
         SpiceInt                handle;

         SpiceDouble             dc  [ ND ];
         SpiceDouble             sum [ MAXSUM ];

         SpiceChar             * kernel = "de421.bsp";

         SpiceBoolean            found;


         /.
         Open a DAF for read. Return a handle referring to the file.
         ./
         dafopr_c ( kernel, &handle );

         /.
         Begin a forward search on the file.
         ./
         dafbfs_c ( handle );

         /.
         Search until a DAF array is found.
         ./
         daffna_c ( &found );

         /.
         Loop while the search finds subsequent DAF arrays.
         ./
         while ( found )
            {

            dafgs_c ( sum );
            dafus_c ( sum, ND, NI, dc, ic );

            printf( " Doubles: %f %f \n", dc[0], dc[1] );
            printf( "Integers: %d %d %d %d %d %d\n\n",
                       (int)ic[0], (int)ic[1], (int)ic[2],
                       (int)ic[3], (int)ic[4], (int)ic[5] );


            /.
            Check for another segment.
            ./
            daffna_c ( &found );
            }

         /.
         Safely close the DAF.
         ./
         dafcls_c ( handle  );

         return ( 0 );
         }


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


       Doubles: -3169195200.000000 1696852800.000000
      Integers: 1 0 1 2 641 310404

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 2 0 1 2 310405 423048

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 3 0 1 2 423049 567372

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 4 0 1 2 567373 628976

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 5 0 1 2 628977 674740

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 6 0 1 2 674741 715224

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 7 0 1 2 715225 750428

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 8 0 1 2 750429 785632

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 9 0 1 2 785633 820836

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 10 0 1 2 820837 944040

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 301 3 1 2 944041 1521324

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 399 3 1 2 1521325 2098608

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 199 1 1 2 2098609 2098620

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 299 2 1 2 2098621 2098632

       Doubles: -3169195200.000000 1696852800.000000
      Integers: 499 4 1 2 2098633 2098644


      Note, the final entries in the integer array contains the segment
      start/end indexes. The output indicates the search proceeded
      from the start of the file (low value index) towards the end
      (high value index).

Restrictions

   None.

Literature_References

   None.

Author_and_Institution

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

Version

   -CSPICE Version 1.0.3, 10-AUG-2021 (JDR)

       Edited the header to comply with NAIF standard.

   -CSPICE Version 1.0.2, 28-JUN-2016 (EDW)

       Edit to Example code, SpiceInts output as ints using
       explicit casting.

   -CSPICE Version 1.0.1, 10-OCT-2012 (EDW)

       Added a functional code example to the -Examples section.

       Removed the obsolete Reference citation to "NAIF
       Document 167.0."

   -CSPICE Version 1.0.0, 01-AUG-1999 (NJB) (IMU)

Index_Entries

   unpack DAF summary