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Math.Floor Method

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Returns the largest integer less than or equal to the specified double-precision floating-point number.

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

Syntax

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

Parameters

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

Return Value

Type: System.Double
The largest integer less than or equal to d. If d is equal to NaN, NegativeInfinity, or PositiveInfinity, that value is returned.

Remarks

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

Examples

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