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PHP array_sum() Function

PHP Array Reference Complete PHP Array Reference

Definition and Usage

The array_sum() function returns the sum of all the values in the array.

Syntax

array_sum(array)

Parameter Description
array Required. Specifies an array

Example 

<?php
$a=array(0=>"5",1=>"15",2=>"25");
echo array_sum($a);
?>

The output of the code above will be:

45

PHP Array Reference Complete PHP Array Reference

From http://www.w3schools.com (Copyright Refsnes Data)