Index of Functions: A B C D E F G H I J K L M N O P Q R S T U V W X
Index Page elemi_c

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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

       elemi_c ( Element of an integer set )

       SpiceBoolean elemi_c ( SpiceInt        item,
                              SpiceCell     * a    )

#### Abstract

       Determine whether an item is an element of an integer set.

#### Required_Reading

       SETS

#### Keywords

       CELLS
       SETS

#### Brief_I/O

       VARIABLE  I/O  DESCRIPTION
       --------  ---  --------------------------------------------------
       item       I   Item to be tested.
       a          I   Set to be tested.

       The function returns SPICETRUE if `item' is an element of `a'.

#### Detailed_Input

       item        is an item which may or may not be an element of
                   the input set.

       a           is a SPICE set.

                   `a' must be declared as an integer SpiceCell.

                   CSPICE provides the following macro, which declares and
                   initializes the cell

                      SPICEINT_CELL           ( a, ASZ );

                   where ASZ is the maximum capacity of `a'.

#### Detailed_Output

       The function returns SPICETRUE if `item' is a member of the set `a',
       and returns SPICEFALSE otherwise.

#### Parameters

       None.

#### Exceptions

       1)  If the `a' cell argument has a type other than SpiceInt, the
           error SPICE(TYPEMISMATCH) is signaled. The function returns
           the value SPICEFALSE.

       2)  If the `a' cell argument does not qualify as a SPICE set, the
           error SPICE(NOTASET) is signaled. SPICE sets have their data
           elements stored in increasing order and contain no duplicate
           elements. The function returns the value SPICEFALSE.

#### Files

       None.

#### Particulars

       This routine uses a binary search to check for the presence in the set
       of the specified item.

#### Examples

       The numerical results shown for this example 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) Check if the elements of a list of integers belong to a given
          integer set.

          Example code begins here.

          /.
             Program elemi_ex1
          ./
          #include <stdio.h>
          #include "SpiceUsr.h"

          int main( )
          {

             /.
             Local constants.
             ./
             #define LISTSZ       6
             #define SETDIM       8

             /.
             Local variables.
             ./
             SPICEINT_CELL      ( a     , SETDIM );
             SpiceInt             i;

             /.
             Set the values of the set and the list of integers.
             ./
             SpiceInt             values [SETDIM] = {
                                                -1, 0, 1, 1, 3, 5, 0, -3 };

             SpiceInt             items  [LISTSZ] = { 6, -1, 0, 2, 3, -2 };

             /.
             Add the values to the integer set using appndi_c. The
             results of these calls results in a cell which does not
             qualify as a set.
             ./
             for ( i = 0; i < SETDIM; i++ )
             {
                appndi_c ( values[i], &a );
             }

             /.
             Initialize the set by validating the cell: remove duplicates
             and sort the elements in increasing order.
             ./
             valid_c ( SETDIM, SETDIM, &a );

             /.
             Check if the items in the list belong to the set.
             ./
             for ( i = 0; i < LISTSZ; i++ )
             {
                if ( elemi_c ( items[i], &a ) )
                {
                   printf( "Item %4d is in the set.\n", items[i] );
                }
                else
                {
                   printf( "Item %4d is NOT in the set.\n", items[i] );
                }
             }

             return ( 0 );
          }

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

          Item    6 is NOT in the set.
          Item   -1 is in the set.
          Item    0 is in the set.
          Item    2 is NOT in the set.
          Item    3 is in the set.
          Item   -2 is NOT in the set.

#### Restrictions

       None.

#### Literature_References

       None.

#### Author_and_Institution

       N.J. Bachman        (JPL)
       C.A. Curzon         (JPL)
       J. Diaz del Rio     (ODC Space)
       H.A. Neilan         (JPL)
       W.L. Taber          (JPL)
       I.M. Underwood      (JPL)

#### Version

       -CSPICE Version 1.1.0, 24-AUG-2021 (JDR)

           Changed the argument name "set" to "a" for consistency with other
           routines.

           Edited the header to comply with NAIF standard. Added complete code
           example.

           Extended description of argument "a" in -Detailed_Input to include
           type and preferred declaration method.

       -CSPICE Version 1.0.0, 07-AUG-2002 (NJB) (CAC) (HAN) (WLT) (IMU)

#### Index_Entries

       element of an integer set

#### Link to routine elemi_c source file elemi_c.c

    Fri Dec 31 18:41:06 2021