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Math.Ceiling Method

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Returns the smallest integral value greater than or equal to the specified double-precision floating-point number.

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

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Shared Function Ceiling ( _
    a As Double _
) As Double
[SecuritySafeCriticalAttribute]
public static double Ceiling(
    double a
)

Parameters

  • a
    Type: System.Double
    A double-precision floating-point number.

Return Value

Type: System.Double
The smallest integral value greater than or equal to a. If a is equal to NaN, NegativeInfinity, or PositiveInfinity, that value is returned. Note that the method returns a Double rather than an integral type.

Remarks

The behavior of this method follows IEEE Standard 754, section 4. This kind of rounding is sometimes called rounding toward positive infinity. In other words, if a is positive, the presence of any fractional component causes a to be rounded to the next highest integer. If a is negative, the rounding operation causes any fractional component of a to be discarded. The operation of this method differs from the Floor method, which supports rounding toward negative infinity.

Examples

The following example illustrates the Ceiling method and contrasts it with the Floor method.

Dim values() As Double = {7.03, 7.64, 0.12, -0.12, -7.1, -7.6}
outputBlock.Text &= "  Value          Ceiling          Floor" & vbCrLf
outputBlock.Text &= vbCrLf
For Each value As Double In values
   outputBlock.Text += String.Format("{0,7} {1,16} {2,14}", _
                     value, Math.Ceiling(value), Math.Floor(value)) & vbCrLf
Next
' The example displays the following output:
'         Value          Ceiling          Floor
'       
'          7.03                8              7
'          7.64                8              7
'          0.12                1              0
'         -0.12                0             -1
'          -7.1               -7             -8
'          -7.6               -7             -8
double[] values = { 7.03, 7.64, 0.12, -0.12, -7.1, -7.6 };
outputBlock.Text += "  Value          Ceiling          Floor\n" + "\n";
foreach (double value in values)
   outputBlock.Text += String.Format("{0,7} {1,16} {2,14}",
                     value, Math.Ceiling(value), Math.Floor(value)) + "\n";
// The example displays the following output:
//         Value          Ceiling          Floor
//       
//          7.03                8              7
//          7.64                8              7
//          0.12                1              0
//         -0.12                0             -1
//          -7.1               -7             -8
//          -7.6               -7             -8

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