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Math.Pow(Double, Double) Method

Definition

Returns a specified number raised to the specified power.

public:
 static double Pow(double x, double y);
public static double Pow (double x, double y);
static member Pow : double * double -> double
Public Shared Function Pow (x As Double, y As Double) As Double

Parameters

x
Double

A double-precision floating-point number to be raised to a power.

y
Double

A double-precision floating-point number that specifies a power.

Returns

The number x raised to the power y.

Examples

The following example uses the Pow method to calculate the value that results from raising 2 to a power ranging from 0 to 32.

int value = 2;
for (int power = 0; power <= 32; power++)
   Console.WriteLine($"{value}^{power} = {(long)Math.Pow(value, power):N0} (0x{(long)Math.Pow(value, power):X})");

// The example displays the following output:
//     2^0 = 1 (0x1)
//     2^1 = 2 (0x2)
//     2^2 = 4 (0x4)
//     2^3 = 8 (0x8)
//     2^4 = 16 (0x10)
//     2^5 = 32 (0x20)
//     2^6 = 64 (0x40)
//     2^7 = 128 (0x80)
//     2^8 = 256 (0x100)
//     2^9 = 512 (0x200)
//     2^10 = 1,024 (0x400)
//     2^11 = 2,048 (0x800)
//     2^12 = 4,096 (0x1000)
//     2^13 = 8,192 (0x2000)
//     2^14 = 16,384 (0x4000)
//     2^15 = 32,768 (0x8000)
//     2^16 = 65,536 (0x10000)
//     2^17 = 131,072 (0x20000)
//     2^18 = 262,144 (0x40000)
//     2^19 = 524,288 (0x80000)
//     2^20 = 1,048,576 (0x100000)
//     2^21 = 2,097,152 (0x200000)
//     2^22 = 4,194,304 (0x400000)
//     2^23 = 8,388,608 (0x800000)
//     2^24 = 16,777,216 (0x1000000)
//     2^25 = 33,554,432 (0x2000000)
//     2^26 = 67,108,864 (0x4000000)
//     2^27 = 134,217,728 (0x8000000)
//     2^28 = 268,435,456 (0x10000000)
//     2^29 = 536,870,912 (0x20000000)
//     2^30 = 1,073,741,824 (0x40000000)
//     2^31 = 2,147,483,648 (0x80000000)
//     2^32 = 4,294,967,296 (0x100000000)
open System

let value = 2
for power = 0 to 32 do
    printfn $"{value}^{power} = {Math.Pow(value, power) |> int64:N0} (0x{Math.Pow(value, power) |> int64:X})"

// The example displays the following output:
//     2^0 = 1 (0x1)
//     2^1 = 2 (0x2)
//     2^2 = 4 (0x4)
//     2^3 = 8 (0x8)
//     2^4 = 16 (0x10)
//     2^5 = 32 (0x20)
//     2^6 = 64 (0x40)
//     2^7 = 128 (0x80)
//     2^8 = 256 (0x100)
//     2^9 = 512 (0x200)
//     2^10 = 1,024 (0x400)
//     2^11 = 2,048 (0x800)
//     2^12 = 4,096 (0x1000)
//     2^13 = 8,192 (0x2000)
//     2^14 = 16,384 (0x4000)
//     2^15 = 32,768 (0x8000)
//     2^16 = 65,536 (0x10000)
//     2^17 = 131,072 (0x20000)
//     2^18 = 262,144 (0x40000)
//     2^19 = 524,288 (0x80000)
//     2^20 = 1,048,576 (0x100000)
//     2^21 = 2,097,152 (0x200000)
//     2^22 = 4,194,304 (0x400000)
//     2^23 = 8,388,608 (0x800000)
//     2^24 = 16,777,216 (0x1000000)
//     2^25 = 33,554,432 (0x2000000)
//     2^26 = 67,108,864 (0x4000000)
//     2^27 = 134,217,728 (0x8000000)
//     2^28 = 268,435,456 (0x10000000)
//     2^29 = 536,870,912 (0x20000000)
//     2^30 = 1,073,741,824 (0x40000000)
//     2^31 = 2,147,483,648 (0x80000000)
//     2^32 = 4,294,967,296 (0x100000000)
Public Module Example
   Public Sub Main
      Dim value As Integer = 2
      For power As Integer = 0 To 32
         Console.WriteLine("{0}^{1} = {2:N0} (0x{2:X})", _
                           value, power, CLng(Math.Pow(value, power)))
      Next
   End Sub
End Module
' The example displays the following output:
'     2^0 = 1 (0x1)
'     2^1 = 2 (0x2)
'     2^2 = 4 (0x4)
'     2^3 = 8 (0x8)
'     2^4 = 16 (0x10)
'     2^5 = 32 (0x20)
'     2^6 = 64 (0x40)
'     2^7 = 128 (0x80)
'     2^8 = 256 (0x100)
'     2^9 = 512 (0x200)
'     2^10 = 1,024 (0x400)
'     2^11 = 2,048 (0x800)
'     2^12 = 4,096 (0x1000)
'     2^13 = 8,192 (0x2000)
'     2^14 = 16,384 (0x4000)
'     2^15 = 32,768 (0x8000)
'     2^16 = 65,536 (0x10000)
'     2^17 = 131,072 (0x20000)
'     2^18 = 262,144 (0x40000)
'     2^19 = 524,288 (0x80000)
'     2^20 = 1,048,576 (0x100000)
'     2^21 = 2,097,152 (0x200000)
'     2^22 = 4,194,304 (0x400000)
'     2^23 = 8,388,608 (0x800000)
'     2^24 = 16,777,216 (0x1000000)
'     2^25 = 33,554,432 (0x2000000)
'     2^26 = 67,108,864 (0x4000000)
'     2^27 = 134,217,728 (0x8000000)
'     2^28 = 268,435,456 (0x10000000)
'     2^29 = 536,870,912 (0x20000000)
'     2^30 = 1,073,741,824 (0x40000000)
'     2^31 = 2,147,483,648 (0x80000000)
'     2^32 = 4,294,967,296 (0x100000000)

Remarks

The following table indicates the return value when various values or ranges of values are specified for the x and y parameters. For more information, see Double.PositiveInfinity, Double.NegativeInfinity, and Double.NaN.

x y Return value
Any value except NaN ±0 1
NaN ±0 1 (NaN on .NET Framework)*
NaN Any value except 0 NaN*
±0 < 0 and an odd integer NegativeInfinity or PositiveInfinity
±0 NegativeInfinity PositiveInfinity
±0 PositiveInfinity +0
±0 > 0 and an odd integer ±0
-1 NegativeInfinity or PositiveInfinity 1
+1 Any value except NaN 1
+1 NaN 1 (NaN on .NET Framework)*
Any value except 1 NaN NaN*
-1 < x < 1 PositiveInfinity +0
< -1 or > 1 PositiveInfinity PositiveInfinity
-1 < x < 1 NegativeInfinity PositiveInfinity
< -1 or > 1 NegativeInfinity +0
PositiveInfinity < 0 +0
PositiveInfinity > 0 PositiveInfinity
NegativeInfinity < 0 and finite and odd integer -0
NegativeInfinity > 0 and finite and odd integer NegativeInfinity
NegativeInfinity < 0 and finite and not an odd integer +0
NegativeInfinity > 0 and finite and not an odd integer PositiveInfinity
±0 < 0 and finite and not an odd integer PositiveInfinity
±0 > 0 and finite and not an odd integer +0
< 0 but not NegativeInfinity Finite non-integer NaN

* These rows don't appear in the full set of rules for pow as defined by the IEEE Standard for Floating-Point Arithmetic. They're included here because .NET disables IEEE 754 floating-point exceptions and thus doesn't differentiate between qNaN (quiet NaN) and sNaN (signalling NaN). The IEEE 754 specification allows this exception disablement.

This method calls into the underlying C runtime, and the exact result or valid input range may differ between different operating systems or architectures.

Applies to

See also