- array_map: documentation ( source)
- array_count_values: documentation ( source)
- str_split: documentation ( source)
<?php
$array = array('apple', 'banana', 'cherry', 'damson');
// For each item in the array, count the letters in the word
$array = array_map(function($value){
$letters = str_split($value);
$counts = array_count_values($letters);
return $counts;
}, $array);