Enumerable.Average Method

Definition

Overloads

Average(IEnumerable<Single>)

Computes the average of a sequence of Single values.

Average(IEnumerable<Nullable<Single>>)

Computes the average of a sequence of nullable Single values.

Average(IEnumerable<Nullable<Int64>>)

Computes the average of a sequence of nullable Int64 values.

Average(IEnumerable<Nullable<Int32>>)

Computes the average of a sequence of nullable Int32 values.

Average(IEnumerable<Nullable<Double>>)

Computes the average of a sequence of nullable Double values.

Average(IEnumerable<Int64>)

Computes the average of a sequence of Int64 values.

Average(IEnumerable<Int32>)

Computes the average of a sequence of Int32 values.

Average(IEnumerable<Double>)

Computes the average of a sequence of Double values.

Average(IEnumerable<Decimal>)

Computes the average of a sequence of Decimal values.

Average(IEnumerable<Nullable<Decimal>>)

Computes the average of a sequence of nullable Decimal values.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Computes the average of a sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Computes the average of a sequence of Single values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Computes the average of a sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Computes the average of a sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Computes the average of a sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Computes the average of a sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Computes the average of a sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Computes the average of a sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Computes the average of a sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Average(IEnumerable<Single>)

Computes the average of a sequence of Single values.

public static float Average (this System.Collections.Generic.IEnumerable<float> source);
Parameters
source
IEnumerable<Single>

A sequence of Single values to calculate the average of.

Returns

The average of the sequence of values.

Exceptions

source is null.

source contains no elements.

Examples

The following code example demonstrates how to use Average(IEnumerable<Int32>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

List<int> grades = new List<int> { 78, 92, 100, 37, 81 };

double average = grades.Average();

Console.WriteLine("The average grade is {0}.", average);

// This code produces the following output:
//
// The average grade is 77.6. 

' Create a list of integers.
Dim grades As New List(Of Integer)(New Integer() {78, 92, 100, 37, 81})

' Determine the average value in the list.
Dim avg As Double = grades.Average()

' Display the output.
MsgBox("The average grade is " & avg)

' This code produces the following output:
'
' The average grade is 77.6

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Nullable<Single>>)

Computes the average of a sequence of nullable Single values.

public static Nullable<float> Average (this System.Collections.Generic.IEnumerable<Nullable<float>> source);
Parameters
source
IEnumerable<Nullable<Single>>

A sequence of nullable Single values to calculate the average of.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source is null.

Examples

The following code example demonstrates how to use Average(IEnumerable<Nullable<Int64>>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

long?[] longs = { null, 10007L, 37L, 399846234235L };

double? average = longs.Average();

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 133282081426.333. 

' Create an array of nullable long values.
Dim longs() As Nullable(Of Long) = {Nothing, 10007L, 37L, 399846234235L}

' Determine the average value in the array.
Dim avg As Nullable(Of Double) = longs.Average()

' Display the output.
MsgBox("The average is " & avg.ToString)

' This code produces the following output:
'
' The average is 133282081426.333

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Nullable<Int64>>)

Computes the average of a sequence of nullable Int64 values.

public static Nullable<double> Average (this System.Collections.Generic.IEnumerable<Nullable<long>> source);
Parameters
source
IEnumerable<Nullable<Int64>>

A sequence of nullable Int64 values to calculate the average of.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source is null.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average(IEnumerable<Nullable<Int64>>) to calculate an average.

long?[] longs = { null, 10007L, 37L, 399846234235L };

double? average = longs.Average();

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 133282081426.333. 

' Create an array of nullable long values.
Dim longs() As Nullable(Of Long) = {Nothing, 10007L, 37L, 399846234235L}

' Determine the average value in the array.
Dim avg As Nullable(Of Double) = longs.Average()

' Display the output.
MsgBox("The average is " & avg.ToString)

' This code produces the following output:
'
' The average is 133282081426.333

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Nullable<Int32>>)

Computes the average of a sequence of nullable Int32 values.

public static Nullable<double> Average (this System.Collections.Generic.IEnumerable<Nullable<int>> source);
Parameters
source
IEnumerable<Nullable<Int32>>

A sequence of nullable Int32 values to calculate the average of.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source is null.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average(IEnumerable<Nullable<Int64>>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

long?[] longs = { null, 10007L, 37L, 399846234235L };

double? average = longs.Average();

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 133282081426.333. 

' Create an array of nullable long values.
Dim longs() As Nullable(Of Long) = {Nothing, 10007L, 37L, 399846234235L}

' Determine the average value in the array.
Dim avg As Nullable(Of Double) = longs.Average()

' Display the output.
MsgBox("The average is " & avg.ToString)

' This code produces the following output:
'
' The average is 133282081426.333

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Nullable<Double>>)

Computes the average of a sequence of nullable Double values.

public static Nullable<double> Average (this System.Collections.Generic.IEnumerable<Nullable<double>> source);
Parameters
source
IEnumerable<Nullable<Double>>

A sequence of nullable Double values to calculate the average of.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source is null.

Examples

The following code example demonstrates how to use Average(IEnumerable<Nullable<Int64>>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

long?[] longs = { null, 10007L, 37L, 399846234235L };

double? average = longs.Average();

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 133282081426.333. 

' Create an array of nullable long values.
Dim longs() As Nullable(Of Long) = {Nothing, 10007L, 37L, 399846234235L}

' Determine the average value in the array.
Dim avg As Nullable(Of Double) = longs.Average()

' Display the output.
MsgBox("The average is " & avg.ToString)

' This code produces the following output:
'
' The average is 133282081426.333

Remarks

If the sum of the elements is too large to represent as a Double, this method returns positive or negative infinity.

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Int64>)

Computes the average of a sequence of Int64 values.

public static double Average (this System.Collections.Generic.IEnumerable<long> source);
Parameters
source
IEnumerable<Int64>

A sequence of Int64 values to calculate the average of.

Returns

The average of the sequence of values.

Exceptions

source is null.

source contains no elements.

Examples

The following code example demonstrates how to use Average(IEnumerable<Int32>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

List<int> grades = new List<int> { 78, 92, 100, 37, 81 };

double average = grades.Average();

Console.WriteLine("The average grade is {0}.", average);

// This code produces the following output:
//
// The average grade is 77.6. 

' Create a list of integers.
Dim grades As New List(Of Integer)(New Integer() {78, 92, 100, 37, 81})

' Determine the average value in the list.
Dim avg As Double = grades.Average()

' Display the output.
MsgBox("The average grade is " & avg)

' This code produces the following output:
'
' The average grade is 77.6

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Int32>)

Computes the average of a sequence of Int32 values.

public static double Average (this System.Collections.Generic.IEnumerable<int> source);
Parameters
source
IEnumerable<Int32>

A sequence of Int32 values to calculate the average of.

Returns

The average of the sequence of values.

Exceptions

source is null.

source contains no elements.

Examples

The following code example demonstrates how to use Average(IEnumerable<Int32>) to calculate an average.

List<int> grades = new List<int> { 78, 92, 100, 37, 81 };

double average = grades.Average();

Console.WriteLine("The average grade is {0}.", average);

// This code produces the following output:
//
// The average grade is 77.6. 

' Create a list of integers.
Dim grades As New List(Of Integer)(New Integer() {78, 92, 100, 37, 81})

' Determine the average value in the list.
Dim avg As Double = grades.Average()

' Display the output.
MsgBox("The average grade is " & avg)

' This code produces the following output:
'
' The average grade is 77.6

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Double>)

Computes the average of a sequence of Double values.

public static double Average (this System.Collections.Generic.IEnumerable<double> source);
Parameters
source
IEnumerable<Double>

A sequence of Double values to calculate the average of.

Returns

The average of the sequence of values.

Exceptions

source is null.

source contains no elements.

Examples

The following code example demonstrates how to use Average(IEnumerable<Int32>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

List<int> grades = new List<int> { 78, 92, 100, 37, 81 };

double average = grades.Average();

Console.WriteLine("The average grade is {0}.", average);

// This code produces the following output:
//
// The average grade is 77.6. 

' Create a list of integers.
Dim grades As New List(Of Integer)(New Integer() {78, 92, 100, 37, 81})

' Determine the average value in the list.
Dim avg As Double = grades.Average()

' Display the output.
MsgBox("The average grade is " & avg)

' This code produces the following output:
'
' The average grade is 77.6

Remarks

If the sum of the elements is too large to represent as a Double, this method returns positive or negative infinity.

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Decimal>)

Computes the average of a sequence of Decimal values.

public static decimal Average (this System.Collections.Generic.IEnumerable<decimal> source);
Parameters
source
IEnumerable<Decimal>

A sequence of Decimal values to calculate the average of.

Returns

The average of the sequence of values.

Exceptions

source is null.

source contains no elements.

Examples

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

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

List<int> grades = new List<int> { 78, 92, 100, 37, 81 };

double average = grades.Average();

Console.WriteLine("The average grade is {0}.", average);

// This code produces the following output:
//
// The average grade is 77.6. 

' Create a list of integers.
Dim grades As New List(Of Integer)(New Integer() {78, 92, 100, 37, 81})

' Determine the average value in the list.
Dim avg As Double = grades.Average()

' Display the output.
MsgBox("The average grade is " & avg)

' This code produces the following output:
'
' The average grade is 77.6

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average(IEnumerable<Nullable<Decimal>>)

Computes the average of a sequence of nullable Decimal values.

public static Nullable<decimal> Average (this System.Collections.Generic.IEnumerable<Nullable<decimal>> source);
Parameters
source
IEnumerable<Nullable<Decimal>>

A sequence of nullable Decimal values to calculate the average of.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source is null.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average(IEnumerable<Nullable<Int64>>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, substitute the elements of the source sequence with elements of the appropriate numerical type.

long?[] longs = { null, 10007L, 37L, 399846234235L };

double? average = longs.Average();

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 133282081426.333. 

' Create an array of nullable long values.
Dim longs() As Nullable(Of Long) = {Nothing, 10007L, 37L, 399846234235L}

' Determine the average value in the array.
Dim avg As Nullable(Of Double) = longs.Average()

' Display the output.
MsgBox("The average is " & avg.ToString)

' This code produces the following output:
'
' The average is 133282081426.333

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Computes the average of a sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence.

public static Nullable<double> Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,Nullable<int>> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Nullable<Int32>>

A transform function to apply to each element.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source or selector is null.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] fruits = { "apple", "banana", "mango", "orange", "passionfruit", "grape" };

double average = fruits.Average(s => s.Length);

Console.WriteLine("The average string length is {0}.", average);

// This code produces the following output:
//
// The average string length is 6.5. 

' Create an array of strings.
Dim fruits() As String =
{"apple", "banana", "mango", "orange", "passionfruit", "grape"}

' Determine the average length of the strings in the array.
Dim avg As Double = fruits.Average(Function(s) s.Length)

' Display the output.
MsgBox("The average string length is " & avg)

' This code produces the following output:
'
' The average string length is 6.5

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Computes the average of a sequence of Single values that are obtained by invoking a transform function on each element of the input sequence.

public static float Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,float> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Single>

A transform function to apply to each element.

Returns

The average of the sequence of values.

Exceptions

source or selector is null.

source contains no elements.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] fruits = { "apple", "banana", "mango", "orange", "passionfruit", "grape" };

double average = fruits.Average(s => s.Length);

Console.WriteLine("The average string length is {0}.", average);

// This code produces the following output:
//
// The average string length is 6.5. 

' Create an array of strings.
Dim fruits() As String =
{"apple", "banana", "mango", "orange", "passionfruit", "grape"}

' Determine the average length of the strings in the array.
Dim avg As Double = fruits.Average(Function(s) s.Length)

' Display the output.
MsgBox("The average string length is " & avg)

' This code produces the following output:
'
' The average string length is 6.5

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Computes the average of a sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence.

public static Nullable<float> Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,Nullable<float>> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Nullable<Single>>

A transform function to apply to each element.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source or selector is null.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] fruits = { "apple", "banana", "mango", "orange", "passionfruit", "grape" };

double average = fruits.Average(s => s.Length);

Console.WriteLine("The average string length is {0}.", average);

// This code produces the following output:
//
// The average string length is 6.5. 

' Create an array of strings.
Dim fruits() As String =
{"apple", "banana", "mango", "orange", "passionfruit", "grape"}

' Determine the average length of the strings in the array.
Dim avg As Double = fruits.Average(Function(s) s.Length)

' Display the output.
MsgBox("The average string length is " & avg)

' This code produces the following output:
'
' The average string length is 6.5

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Computes the average of a sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence.

public static Nullable<double> Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,Nullable<long>> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Nullable<Int64>>

A transform function to apply to each element.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] numbers = { "10007", "37", "299846234235" };

double average = numbers.Average(num => Convert.ToInt64(num));

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 99948748093. 

' Create an array of strings.
Dim numbers() As String = {"10007", "37", "299846234235"}

' Determine the average number after converting each
' string to an Int64 value.
Dim avg As Double =
numbers.Average(Function(number) Convert.ToInt64(number))

' Display the output.
MsgBox("The average is " & avg)

' This code produces the following output:
'
' The average is 99948748093

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Computes the average of a sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence.

public static Nullable<double> Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,Nullable<double>> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Nullable<Double>>

A transform function to apply to each element.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source or selector is null.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] numbers = { "10007", "37", "299846234235" };

double average = numbers.Average(num => Convert.ToInt64(num));

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 99948748093. 

' Create an array of strings.
Dim numbers() As String = {"10007", "37", "299846234235"}

' Determine the average number after converting each
' string to an Int64 value.
Dim avg As Double =
numbers.Average(Function(number) Convert.ToInt64(number))

' Display the output.
MsgBox("The average is " & avg)

' This code produces the following output:
'
' The average is 99948748093

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Computes the average of a sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence.

public static Nullable<decimal> Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,Nullable<decimal>> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Nullable<Decimal>>

A transform function to apply to each element.

Returns

The average of the sequence of values, or null if the source sequence is empty or contains only values that are null.

Exceptions

source or selector is null.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] numbers = { "10007", "37", "299846234235" };

double average = numbers.Average(num => Convert.ToInt64(num));

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 99948748093. 

' Create an array of strings.
Dim numbers() As String = {"10007", "37", "299846234235"}

' Determine the average number after converting each
' string to an Int64 value.
Dim avg As Double =
numbers.Average(Function(number) Convert.ToInt64(number))

' Display the output.
MsgBox("The average is " & avg)

' This code produces the following output:
'
' The average is 99948748093

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Computes the average of a sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence.

public static double Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,long> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Int64>

A transform function to apply to each element.

Returns

The average of the sequence of values.

Exceptions

source or selector is null.

source contains no elements.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>) to calculate an average.

string[] numbers = { "10007", "37", "299846234235" };

double average = numbers.Average(num => Convert.ToInt64(num));

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 99948748093. 

' Create an array of strings.
Dim numbers() As String = {"10007", "37", "299846234235"}

' Determine the average number after converting each
' string to an Int64 value.
Dim avg As Double =
numbers.Average(Function(number) Convert.ToInt64(number))

' Display the output.
MsgBox("The average is " & avg)

' This code produces the following output:
'
' The average is 99948748093

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Computes the average of a sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence.

public static double Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,int> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Int32>

A transform function to apply to each element.

Returns

The average of the sequence of values.

Exceptions

source or selector is null.

source contains no elements.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>) to calculate an average.

string[] fruits = { "apple", "banana", "mango", "orange", "passionfruit", "grape" };

double average = fruits.Average(s => s.Length);

Console.WriteLine("The average string length is {0}.", average);

// This code produces the following output:
//
// The average string length is 6.5. 

' Create an array of strings.
Dim fruits() As String =
{"apple", "banana", "mango", "orange", "passionfruit", "grape"}

' Determine the average length of the strings in the array.
Dim avg As Double = fruits.Average(Function(s) s.Length)

' Display the output.
MsgBox("The average string length is " & avg)

' This code produces the following output:
'
' The average string length is 6.5

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Computes the average of a sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.

public static double Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,double> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values to calculate the average of.

selector
Func<TSource,Double>

A transform function to apply to each element.

Returns

The average of the sequence of values.

Exceptions

source or selector is null.

source contains no elements.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] numbers = { "10007", "37", "299846234235" };

double average = numbers.Average(num => Convert.ToInt64(num));

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 99948748093. 

' Create an array of strings.
Dim numbers() As String = {"10007", "37", "299846234235"}

' Determine the average number after converting each
' string to an Int64 value.
Dim avg As Double =
numbers.Average(Function(number) Convert.ToInt64(number))

' Display the output.
MsgBox("The average is " & avg)

' This code produces the following output:
'
' The average is 99948748093

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence.

public static decimal Average<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,decimal> selector);
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

A sequence of values that are used to calculate an average.

selector
Func<TSource,Decimal>

A transform function to apply to each element.

Returns

The average of the sequence of values.

Exceptions

source or selector is null.

source contains no elements.

The sum of the elements in the sequence is larger than MaxValue.

Examples

The following code example demonstrates how to use Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>) to calculate an average.

Note

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

string[] numbers = { "10007", "37", "299846234235" };

double average = numbers.Average(num => Convert.ToInt64(num));

Console.WriteLine("The average is {0}.", average);

// This code produces the following output:
//
// The average is 99948748093. 

' Create an array of strings.
Dim numbers() As String = {"10007", "37", "299846234235"}

' Determine the average number after converting each
' string to an Int64 value.
Dim avg As Double =
numbers.Average(Function(number) Convert.ToInt64(number))

' Display the output.
MsgBox("The average is " & avg)

' This code produces the following output:
'
' The average is 99948748093

Remarks

In Visual Basic query expression syntax, an Aggregate Into Average() clause translates to an invocation of Average.