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Procedure
Abstract
Required_Reading
Keywords
Brief_I/O
Detailed_Input
Detailed_Output
Parameters
Exceptions
Files
Particulars
Examples
Restrictions
Literature_References
Author_and_Institution
Version
Index_Entries

Procedure

   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

   Example (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 );
      }

   Example (2):

   Use a simple routine 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 segments description for each array found, then
   closes the DAF.

      #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 );
         }

   The program outputs:

       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)
   I.M. Underwood  (JPL)

Version

   -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
Wed Apr  5 17:54:31 2017