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Метод SqlGeography.BufferWithTolerance

Returns a geometric object representing the union of all point values whose distance from a SqlGeography instance is less than or equal to a specified value, allowing for a specified tolerance.

Пространство имен:  Microsoft.SqlServer.Types
Сборка:  Microsoft.SqlServer.Types (в Microsoft.SqlServer.Types.dll)

Синтаксис

'Декларация
<SqlMethodAttribute(IsDeterministic := True, IsPrecise := False)> _
Public Function BufferWithTolerance ( _
    distance As Double, _
    tolerance As Double, _
    relative As Boolean _
) As SqlGeography
'Применение
Dim instance As SqlGeography 
Dim distance As Double 
Dim tolerance As Double 
Dim relative As Boolean 
Dim returnValue As SqlGeography 

returnValue = instance.BufferWithTolerance(distance, _
    tolerance, relative)
[SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)]
public SqlGeography BufferWithTolerance(
    double distance,
    double tolerance,
    bool relative
)
[SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)]
public:
SqlGeography^ BufferWithTolerance(
    double distance, 
    double tolerance, 
    bool relative
)
[<SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)>]
member BufferWithTolerance : 
        distance:float * 
        tolerance:float * 
        relative:bool -> SqlGeography
public function BufferWithTolerance(
    distance : double, 
    tolerance : double, 
    relative : boolean
) : SqlGeography

Параметры

  • distance
    Тип: System.Double
    Is a double that specifies the distance from the SqlGeography instance around which to calculate the buffer.
  • tolerance
    Тип: System.Double
    Is a double that specifies the tolerance of the buffer distance.The tolerance value refers to the maximum variation in the ideal buffer distance for the returned linear approximation.For example, the ideal buffer distance of a point is a circle, but this must be approximated by a polygon. The smaller the tolerance, the more points the polygon will have, which increases the complexity of the result, but decreases the error.
  • relative
    Тип: System.Boolean
    Is a bool that specifies whether the tolerance value is relative or absolute. If true, then tolerance is relative and is calculated as the product of the tolerance parameter and the angular extent * equatorial radius of the ellipsoid. If false, tolerance is absolute and the tolerance value is the absolute maximum variation in the ideal buffer distance for the returned linear approximation.

Возвращаемое значение

Тип: Microsoft.SqlServer.Types.SqlGeography
A SqlGeography instance representing the union of all point values whose distance from a SqlGeography instance is less than or equal to a specified value.

Замечания

A negative buffer removes all points within the given distance of the boundary of the SqlGeography instance.

См. также

Справочник

SqlGeography Класс

Пространство имен Microsoft.SqlServer.Types