# Aggregation functions
Source: https://www.stedi.com/docs/edi-platform/mappings/jsonata/jsonata-functions/aggregation

***

## title: Aggregation functions

## $sum

**Signature:** `$sum(array)`

**Parameters:**

* `array` - An array of numbers.

Returns the arithmetic sum of an array of numbers. It is an error if the input array contains an item which isn't a number.

**Example**

| Expression          | Result |
| ------------------- | ------ |
| `$sum([5,1,3,7,4])` | `20`   |

## $max

**Signature:** `$max(array)`

**Parameters:**

* `array` - An array of numbers.

Returns the maximum number in an array of numbers. It is an error if the input array contains an item which isn't a number.

**Example**

| Expression          | Result |
| ------------------- | ------ |
| `$max([5,1,3,7,4])` | `7`    |

## $min

**Signature:** `$min(array)`

**Parameters:**

* `array` - An array of numbers.

Returns the minimum number in an array of numbers. It is an error if the input array contains an item which isn't a number.

**Example**

| Expression          | Result |
| ------------------- | ------ |
| `$min([5,1,3,7,4])` | `1`    |

## $average

**Signature:** `$average(array)`

**Parameters:**

* `array` - An array of numbers.

Returns the mean value of an array of numbers. It is an error if the input array contains an item which isn't a number.

**Example**

| Expression              | Result |
| ----------------------- | ------ |
| `$average([5,1,3,7,4])` | `4`    |