IEEE_UNORDERED(3I) Last changed: 1-6-98
NAMEIEEE_UNORDERED - Tests for x or y being a NaN
SYNOPSISIEEE_UNORDERED ([X=]x, [Y=]y)
IMPLEMENTATION
UNICOS/mk and IRIX systems
CRAY T90 systems that support IEEE floating-point arithmetic
STANDARDS
CF90 and MIPSpro 7 Fortran 90 compiler extension to Fortran 90
IEEE Standard for Binary Floating-point Arithmetic
DESCRIPTION
The IEEE_UNORDERED intrinsic function tests for x or y being a NaN.
It accepts the following arguments:
x Must be of type real. Can be a scalar or an array.
y Must be of type real. y must be conformable with x.
IEEE_UNORDERED is an elemental function. The name of this intrinsic
cannot be passed as an argument.
NOTES
The IEEE intrinsic procedures use the named constants contained in a
system module, so you must include one of the following statements in
your program:
* On UNICOS and UNICOS/mk systems: USE CRI_IEEE_DEFINITIONS
* On UNICOS, UNICOS/mk, and IRIX systems: USE FTN_IEEE_DEFINITIONS
The CRI_IEEE_DEFINITIONS module is obsolescent. It will be removed
for the CF90 4.0 release.
RETURN VALUES
The result type and type parameter are default logical. If either x
or y is an array, the result is an array of the same shape as one of
the array arguments.
The return value is .TRUE. if either x or y is a NaN, otherwise the
return value is .FALSE.. The operation does not raise the Invalid
Operation interrupt.
If x and y are both scalar, the result is a scalar.
If x is an array and y is scalar, the result is an array in which each
element has the value .TRUE. or .FALSE., depending on whether x
i
is unordered with y.
If x is scalar and y is an array, the result is an array in which each
element has the value .TRUE. or .FALSE., depending on whether x is
unordered with y .
i
If x is an array and y is an array, the result is an array in which
each element has the value .TRUE. or .FALSE., depending on whether
x is unordered with y .
i i
EXAMPLES
REAL x,y
... ! Compute X.
IF (IEEE_UNORDERED(x, y)) THEN
... ! Do something.
ELSE
... ! Do something else.
END IF
SEE ALSO
Intrinsic Procedures Reference Manual, publication SR-2138, for the
printed version of this man page.
