Remarks

Not-a-Number (NaN) values are returned when the result of a double operation is undefined.

A NaN value is not equal to any other value, including another NaN value.

The value of this field is obtained by dividing double zero by zero.

Note: double.NaN represents one of many possible NaN values. To test whether a double value is a NaN, use the double.IsNaN(double) method.

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Requirements

Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Assembly Versions: 1.0.5000.0, 2.0.0.0