Mean

Mean( arrayOrSet )
Mean( arrayOrSet )
Mean( arrayOrSet )
Mean( arrayOrSet )
mean( arrayOrSet )
Mean( arrayOrSet )

The run time of Mean is dependent on the number of elements in the underlying set or page (it’s linear, or O(1)). For very large sets or pages, executing Mean might result in a query timeout error.

To work around this, you may specify a larger query timeout via the driver that you are using.

Description

The Mean function returns the average value of the items in arrayOrSet, which is an Array, Page, or Set. The mean is calculated by dividing the sum of the arrayOrSet's values by the count of the arrayOrSet's values.

Parameters

Argument Type Definition and Requirements

arrayOrSet

Array, Page, or Set

The array, page, or set that should have its average value calculated.

Returns

A Number representing the average value of all items in arrayOrSet.

Examples

The following query returns the average of the items in the provided array:

Value result = await client.Query(
  Mean(Arr(1, 2, 3, 4, 5, 6, 7, 8, 9, 10))
);

IResult<Value> data = result.To<Value>();
data.Match(
  Success: value => Console.WriteLine($"{value}"),
  Failure: error => Console.WriteLine($"Query failed:\n{error}")
);
DoubleV(5.5)
result, err := client.Query(
  f.Mean(f.Arr{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}))

if (err != nil) {
  fmt.Println(err)
} else {
  fmt.Println(result)
}
5.5
System.out.println(
    client.query(
        Mean(
            Arr(
                Value(1), Value(2), Value(3), Value(4), Value(5),
                Value(6), Value(7), Value(8), Value(9), Value(10)
            )
        )
    ).get()
);
5.5
client.query(
  q.Mean([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
)
.then((ret) => console.log(ret))
5.5
print(client.query(
  q.mean([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
))
5.5
println(Await.result(
  client.query(
    Mean(Arr(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)),
  ),
  5.seconds)
)
5.5

Is this article helpful? 

Tell Fauna how the article can be improved:
 Visit Fauna's forums or email docs@fauna.com

Thank you for your feedback!