_isunordered, _isunorderedf (Windows Embedded CE 6.0)

1/5/2010

_isunordered compares two doubles to determine if they are unordered.

_isunorderedf compares two floats to determine if they are unordered.

Syntax

int __cdecl _isunordered(
  double arg1,
  double arg2
);

int __cdecl _isunorderedf(
  float arg1,
  float arg2
);

Returns a Boolean value.

TRUE indicates that arg1 and arg2 are unordered.

IEEE-754 floating-point comparison can have four separate result values: less-than, equal-to, greater-than or unordered.

The first three conditions can be tested using normal C operators, and this function is used to test for the last condition.

Two values are unordered if either is a NaN. This means that a NaN is not equal to any value, even itself.

The C++ compiler returns a bool value instead of an int.