HpcLinqQueryable.AverageAsQuery Method (IQueryable)

Article
04/22/2013

Creates a query that you can run later to compute the average of a set of Nullable<Int64> values.

Namespace: Microsoft.Hpc.Linq
Assembly: Microsoft.Hpc.Linq (in Microsoft.Hpc.Linq.dll)

Usage

'Usage
Dim source As IQueryable(Of Nullable(Of Long))
Dim returnValue As IQueryable(Of Nullable(Of Double))

returnValue = HpcLinqQueryable.AverageAsQuery(source)

Syntax

'Declaration
<ExtensionAttribute> _
Public Shared Function AverageAsQuery ( _
    source As IQueryable(Of Nullable(Of Long)) _
) As IQueryable(Of Nullable(Of Double))

[ExtensionAttribute] 
public static IQueryable<Nullable<double>> AverageAsQuery (
    IQueryable<Nullable<long>> source
)

[ExtensionAttribute] 
public:
static IQueryable<Nullable<double>>^ AverageAsQuery (
    IQueryable<Nullable<long long>>^ source
)

/** @attribute ExtensionAttribute() */ 
public static IQueryable<Nullable<double>> AverageAsQuery (
    IQueryable<Nullable<long>> source
)

ExtensionAttribute 
public static function AverageAsQuery (
    source : IQueryable<Nullable<long>>
) : IQueryable<Nullable<double>>

Parameters

source
An System.Linq.IQueryable<Nullable<Int64>> interface for the set of values for which you want to calculate the average.

Return Value

An IQueryable interface for the query.

Exceptions

Exception type	Condition
ArgumentNullException	The specified source parameter is a null reference (Nothing in Visual Basic).

Remarks

Use this method if you want to perform the same query as the Average method, but want to delay running the query instead of generating results immediately.

Use the Submit method to run the query. Use the GetEnumerator method or the foreach statement of the C# language (For Each in Visual Basic) to get the results of the query. The enumerator contains a single Nullable<Double> element, which is the average of the specified set of values.

To create a query that calculates the average of a set of Nullable<Int64> values that are calculated from a set of records by using a specified function, use the AverageAsQuery(Generic IQueryable,Generic Expression) form of the method. For information about versions of this method that calculate the average for values with other data types, see the AverageAsQuery method.

In Visual Basic and C#, you can call this method as an instance method on any object of type IQueryable<Nullable<Int64>>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

For more information about how the query runs and its behavior, see the Remarks section for the Average method.

Platform Note: This method was introduced in Windows HPC Server 2008 R2 with Service Pack 2 (SP2) and is not supported in previous versions.(SP2) and is not supported in previous versions.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Platforms

Development Platforms

Windows XP, Windows Vista, Windows 7, Windows 8, Windows Server 2003, Windows Server 2008, Windows Server 2008 R2, Windows Server 2012

Target Platforms

Windows XP, Windows Vista, Windows 7, Windows Server 2003, Windows Server 2003 R2, Windows Server 2008, Windows Server 2008 R2, with HPC Pack Client Utilities