Math.Ceiling Method (Double)

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

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

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 that is greater than or equal to a. If a is equal to NaN, NegativeInfinity, or PositiveInfinity, that value is returned. Note that this method returns a Double instead of an integral type.

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(Double) method, which supports rounding toward negative infinity.

The following example illustrates the Math.Ceiling(Double) method and contrasts it with the Floor(Double) method.

double[] values = {7.03, 7.64, 0.12, -0.12, -7.1, -7.6};
Console.WriteLine("  Value          Ceiling          Floor\n");
foreach (double value in values)
   Console.WriteLine("{0,7} {1,16} {2,14}", 
                     value, Math.Ceiling(value), Math.Floor(value));
// The example displays the following output to the console: 
//         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

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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