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Double.IsNaN(Double) Method

Definition

Namespace:
System
Assemblies:
mscorlib.dll, System.Runtime.dll
Assemblies:
netstandard.dll, System.Runtime.dll
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
Double.cs
Source:
Double.cs
Source:
Double.cs
Source:
Double.cs
Source:
Double.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Returns a value that indicates whether the specified value is not a number (NaN).

public:
 static bool IsNaN(double d);
public:
 static bool IsNaN(double d) = System::Numerics::INumberBase<double>::IsNaN;
public static bool IsNaN(double d);
static member IsNaN : double -> bool
Public Shared Function IsNaN (d As Double) As Boolean

Parameters

d
Double

A double-precision floating-point number.

Returns

true if d evaluates to NaN; otherwise, false.

Implements

Examples

The following code example illustrates the use of IsNaN:

// This will return true.
if (Double.IsNaN(0 / zero))
 Console.WriteLine("Double.IsNan() can determine whether a value is not-a-number.");
// This will return true.
if Double.IsNaN(0. / zero) then
 printfn "Double.IsNan() can determine whether a value is not-a-number."
' This will return true.
If Double.IsNaN(0 / zero) Then
 Console.WriteLine("Double.IsNan() can determine whether a value is not-a-number.")
End If

Remarks

Floating-point operations return NaN to signal that result of the operation is undefined. For example, dividing 0.0 by 0.0 results in NaN.

Note

IsNaN returns false if a Double value is either PositiveInfinity or NegativeInfinity. To test for these values, use the IsInfinity, IsPositiveInfinity, and IsNegativeInfinity methods.

Applies to

See also


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