The `sum`

function returns a number that is the sum of the numeric values of each node in a given node-set.

### Syntax

sum(node-set)

### Arguments

`node-set`

- The node-set to be evaluated. Each node in this node-set is evaluated as if it were passed to the number() function, and a sum of the resulting numbers is returned.

### Returns

A number.

### Notes

*(None)*

### Defined

### Gecko support

Supported.