# C# Eval Expression LINQ Dynamic - Average

## LINQ Dynamic Average Examples

C# Dynamic LINQ Average examples using an Expression Evaluator.

## Average - Simple

This C# example uses the LINQ Average method with a dynamic expression to get the average of all numbers in an array.

### LINQ

```int[] numbers = {5, 4, 1, 3, 9, 8, 6, 7, 2, 0};

var averageNum = numbers.Average();

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

Try it online

### LINQ Execute

```int[] numbers = {5, 4, 1, 3, 9, 8, 6, 7, 2, 0};

var averageNum = numbers.Execute<double>("Average()");

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

Try it online

### Result

``````The average number is 4.5.
``````

## Average - Projection

This C# example uses the LINQ Average method with a dynamic expression to get the average length of the words in the array.

### LINQ

```string[] words = {"cherry", "apple", "blueberry"};

var averageLength = words.Average(w => w.Length);

Console.WriteLine("The average word length is {0} characters.", averageLength);
```

Try it online

### LINQ Execute

```string[] words = {"cherry", "apple", "blueberry"};

var averageLength = words.Execute<double>("Average(w => w.Length)");

Console.WriteLine("The average word length is {0} characters.", averageLength);
```

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### Result

``````The average word length is 6.66666666666667 characters.
``````

## Average - Grouped

This C# example uses the LINQ Average method with a dynamic expression to get the average price of each category's products.

### LINQ

```var products = getList();

var categories = products.GroupBy(prod => prod.Category).Select(g => new {Category = g.Key, AveragePrice = g.Average(prod => prod.UnitPrice)});

foreach (var categorie in categories)
{
Console.WriteLine("Category : " + categorie.Category + " AveragePrice : " +categorie.AveragePrice );
}
```

Try it online

### LINQ Execute

```private void uiAverage_Grouped_LINQ_Execute_Click(object sender, EventArgs e)
{
var products = My.GetProductList();

var categories = products.Execute("GroupBy(prod => prod.Category).Select(g => new { Category = g.Key, AveragePrice = g.Average(prod => prod.UnitPrice) })");

var sb = new StringBuilder();

My.ObjectDumper.Write(sb, categories);

My.Result.Show(My.LinqResultType.LinqExecute, uiResult, sb);
}
```

### Result

``````Category=Beverages
Category=Condiments
Category=Produce
Category=Meat/Poultry
Category=Seafood
Category=Dairy Products
Category=Confections
Category=Grains/Cereals	AveragePrice=37.979166666666666666666666667
AveragePrice=23.0625
AveragePrice=32.3700
AveragePrice=54.006666666666666666666666667
AveragePrice=20.6825
AveragePrice=28.7300
AveragePrice=25.1600
AveragePrice=20.2500
``````