_isunordered, _isunorderedf
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_isunordered, _isunorderedf 

Visual Studio 2005

_isunordered compares two double precision numbers to determine if they are unordered.

_isunorderedf compares two floating-point numbers to determine if they are unordered.

int __cdecl _isunordered(
  double arg1,
  double arg2

int __cdecl _isunorderedf(
  float arg1,
  float arg2



[in] The value to be compared to arg2.

[in] The value to be compared to arg1.

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.

Routine Required header Architecture



x86, ARM, SH-4, MIPS



x86, ARM, SH-4, MIPS

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