PHP Manual: Returns the sum of all values in the sequence

abstract public intfloat Ds\Sequence::sum()

Returns the sum of all values in the sequence.

Note:
Arrays and objects are considered equal to zero when calculating the sum.

This function has no parameters.

The sum of all the values in the sequence as either a float or int depending on the values in the sequence.

Example #1 Ds\Sequence::sum integer example

<?php
$sequence = new \Ds\Vector([1, 2, 3]);
var_dump($sequence->sum());
?>

The above example will output something similar to:

int(6)

Example #2 Ds\Sequence::sum float example

<?php
$sequence = new \Ds\Vector([1, 2.5, 3]);
var_dump($sequence->sum());
?>

The above example will output something similar to:

float(6.5)