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Queryable.Average Method (IQueryable(Of Int32))

Computes the average of a sequence of Int32 values.

Namespace:  System.Linq
Assembly:  System.Core (in System.Core.dll)

<ExtensionAttribute> _
Public Shared Function Average ( _
	source As IQueryable(Of Integer) _
) As Double
Dim source As IQueryable(Of Integer)
Dim returnValue As Double 

returnValue = source.Average()


Type: System.Linq.IQueryable(Of Int32)

A sequence of Int32 values to calculate the average of.

Return Value

Type: System.Double
The average of the sequence of values.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IQueryable(Of Int32). 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).


source is Nothing.


source contains no elements.

The Average(IQueryable(Of Int32)) method generates a MethodCallExpression that represents calling Average(IQueryable(Of Int32)) itself. It then passes the MethodCallExpression to the Execute(Of TResult)(Expression) method of the IQueryProvider represented by the Provider property of the source parameter.

The query behavior that occurs as a result of executing an expression tree that represents calling Average(IQueryable(Of Int32)) depends on the implementation of the type of the source parameter. The expected behavior is that it calculates the average of the values in source.

The following code example demonstrates how to use Average(IQueryable(Of Int32)) to calculate the average of a sequence of values.

Dim grades As New List(Of Integer)(New Integer() {78, 92, 100, 37, 81})

Dim average As Double = grades.AsQueryable().Average()

MsgBox(String.Format("The average grade is {0}.", average))

' This code produces the following output: 

' The average grade is 77.6. 

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

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

.NET Framework

Supported in: 3.5