Procedure

            EVEN  ( Is an integer even? )
 
      LOGICAL FUNCTION EVEN ( I )
 

Abstract

      Determine whether an integer is even.

Required_Reading

     None.

Keywords

      NUMBERS

Declarations

 
      INTEGER          I
 

Brief_I/O

      VARIABLE  I/O  DESCRIPTION
      --------  ---  --------------------------------------------------
      I          I   The integer in question.
      EVEN       O   True if I is even, otherwise false.

Detailed_Input

      I           is the integer to be tested for evenness.

Detailed_Output

      EVEN        is true if I is even, false if I is odd.

Parameters

      None.

Exceptions

     Error free.

Files

      None.

Particulars

      None.

Examples

      Let ENDPTS contain a series of endpoints,

         a , b , ..., a , b
          1   1        n   n

      representing an ordered collection of disjoint intervals,

         a   <  b   < a
          i  -   i     i+1

      The following code fragment uses EVEN to determine whether
      an arbitrary value X is contained in any of the intervals.

         CONTAINED = .FALSE.

         DO I = 1, N-1
            IF ( X .GE. ENDPTS(I)  .AND.  X .LE. ENDPTS(I+1) ) THEN
               CONTAINED = ( .NOT. EVEN ( I ) )
            END IF
         END DO

Restrictions

      None.

Literature_References

      None.

Author_and_Institution

      I.M. Underwood  (JPL)

Version

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

        Comment section for permuted index source lines was added
        following the header.

    SPICELIB Version 1.0.0, 31-JAN-1990 (IMU)