neqv(3I)

NAME
     NEQV, XOR - Computes logical difference

SYNOPSIS
     NEQV ([I=]i,[J=]j)
     XOR ([I=]i,[J=]j)

IMPLEMENTATION
     UNICOS, UNICOS/mk, IRIX systems

     CF90 and MIPSpro 7 Fortran 90:  NEQV, XOR

     MIPSpro Fortran 77:  XOR

STANDARDS
     Fortran extensions

DESCRIPTION
     NEQV and XOR are two names for the same routine.  NEQV and XOR are
     elemental functions.  They accept the following arguments:

     i         Must be of type Boolean, integer, real, logical, or Cray
               pointer.

     j         Must be of type Boolean, integer, real, logical, or Cray
               pointer.

NOTES
     These routines are outmoded.  Refer to the Fortran Language Reference
     Manual, Volume 3, for information about outmoded features and their
     preferred standard alternatives.  The name of this intrinsic cannot be
     passed as an argument.

CAUTIONS
     Unexpected results can occur when Boolean functions are declared
     external and then used with logical arguments.  The external Boolean
     functions always treat their arguments as type Boolean and return a
     Boolean result on UNICOS and UNICOS/mk systems.  On IRIX systems, they
     return an integer result.

RETURN VALUES
     When given two arguments of type logical, NEQV and XOR compute a
     logical difference and return a logical result.  When given two
     arguments of type Boolean, integer, real, or pointer, NEQV and XOR
     compute a bit-wise logical difference and return a Boolean result.

     The following tables show both the logical difference and bit-wise
     logical difference.  NEQV is shown in the tables, but XOR produces
     identical results.

     -----------------------------------------------------------------
        Logical        Logical          (Logical Variable 1) NEQV
      Variable 1     Variable 2           (Logical Variable 2)
     -----------------------------------------------------------------
           T              T                         F
           T              F                         T
           F              T                         T
           F              F                         F
     -----------------------------------------------------------------

     --------------------------------------------------------------
        Bit of        Bit of          (Bit of Variable 1) NEQV
      Variable 1    Variable 2           (Bit of Variable 2)
     --------------------------------------------------------------
          1             1                        0
          1             0                        1
          0             1                        1
          0             0                        0
     --------------------------------------------------------------

EXAMPLES
     The following section of Fortran code shows the NEQV function used
     with two arguments of type logical.  XOR is used in the same manner
     and produces the same results.

          LOGICAL L1, L2, L3
          ...
          L3 = NEQV(L1,L2)

     The following section of Fortran code shows the NEQV function used
     with two arguments of type integer.  XOR is used in the same manner
     and produces the same results.  The bit patterns of the arguments and
     results are also given.  For clarity, only the rightmost 8 bits are
     shown.

   INTEGER I1, I2, I3
   I1 = 12
   I2 = 10
   ...
   I3 = NEQV(I1,I2)
       -------------------------------     -------------------------------
      | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 |   | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 |
       -------------------------------     -------------------------------
                        I1                               I2

                     -------------------------------
                    | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 |
                     -------------------------------
                                       I3

SEE ALSO
     Intrinsic Procedures Reference Manual for the printed version of this
     man page.