共用方式為


Math.Pow Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Returns a specified number raised to the specified power.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Shared Function Pow ( _
    x As Double, _
    y As Double _
) As Double
[SecuritySafeCriticalAttribute]
public static double Pow(
    double x,
    double y
)

Parameters

  • x
    Type: System.Double
    A double-precision floating-point number to be raised to a power.
  • y
    Type: System.Double
    A double-precision floating-point number that specifies a power.

Return Value

Type: System.Double
The number x raised to the power y.

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.

Parameters

Return Value

x or y = NaN

NaN

x = Any value except NaN; y = 0

1

x = NegativeInfinity; y < 0

0

x = NegativeInfinity; y is a positive odd integer

NegativeInfinity

x = NegativeInfinity; y is positive but not an odd integer

PositiveInfinity

x < 0 but not NegativeInfinity; y is not an integer, NegativeInfinity, or PositiveInfinity

NaN

x = -1; y = NegativeInfinity or PositiveInfinity

NaN

-1 < x < 1; y = NegativeInfinity

PositiveInfinity

-1 < x < 1; y = PositiveInfinity

0

x < -1 or x > 1; y = NegativeInfinity

0

x < -1 or x > 1; y = PositiveInfinity

PositiveInfinity

x = 0; y < 0

PositiveInfinity

x = 0; y > 0

0

x = 1; y is any value except NaN

1

x = PositiveInfinity; y < 0

0

x = PositiveInfinity; y > 0

PositiveInfinity

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.

Public Module Example
   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim value As Integer = 2
      For power As Integer = 0 To 32
         outputBlock.Text += String.Format("{0}^{1} = {2:N0} (0x{2:X})", _
                           value, power, CLng(Math.Pow(value, power))) + vbCrLf
      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)
using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      int value = 2;
      for (int power = 0; power <= 32; power++)
         outputBlock.Text += String.Format("{0}^{1} = {2:N0} (0x{2:X})",
                           value, power, (long)Math.Pow(value, power)) + "\n";
   }
}
// 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)

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

See Also

Reference