Grouping arrays in php and count data - php

Question

Recently I am working on a project that categorises 'Superheros' and 'Supervillains' based on their 'Franchaise' and origin of 'Superpower'. I want to fetch data from database as as Array #1 and displays them as Array #2 in php.
Array #1
Array
(
[0] => Array
(
[id] => 101
[Name] => Superman
[Franchise] => DC Comics
[Superpower] => Inherent
)
[1] => Array
(
[id] => 908
[Name] => Batman
[Franchise] => DC Comics
[Superpower] => Acquired
)
[2] => Array
(
[id] => 228
[Name] => Wolverine
[Franchise] => Marvel
[Superpower] => Acquired
)
[3] => Array
(
[id] => 158
[Name] => Iron Man
[Franchise] => Marvel
[Superpower] => Acquired
)
[4] => Array
(
[id] => 978
[Name] => Thor
[Franchise] => Marvel
[Superpower] => Inherent
)
)
Array #1 elements have to be grouped based on their 'Franchise' and count how many of them are 'Inherent' or 'Acquired' in terms of 'Superpower'.
Array #2
Array
(
[DC Comics] => Array
(
[Inherent] => 1
[Acquired] => 1
)
[Marvel] => Array
(
[Inherent] => 1
[Acquired] => 2
)
)

Answer 1

Here is your code without much logic,
foreach ($array1 as $val) {
if(!isset($array2[$val['Franchise']])) {
$array2[$val['Franchise']] = array('Inherent' => 0, 'Acquired' => 0);
}
$array2[$val['Franchise']][$val['Superpower']]++;
}
print_r($array2);

Answer 2

array_column() function to aggregate an inner key from a 2D array.
array_count_values() function counts all the values of an array.
Use this code snippet for count values:
$a = array ( array ("id" => "101", "Name" => "Superman", "Franchise" => "DC Comics", "Superpower" => "Inherent" ),
array ( "id" => "908", "Name" => "Batman", "Franchise" => "DC Comics", "Superpower" => "Acquired" ),
array ( "id" => "228", "Name" => "Wolverine", "Franchise" => "Marvel", "Superpower" => "Acquired" ),
array ( "id" => "158", "Name" => "Iron Man", "Franchise" => "Marvel", "Superpower" => "Acquired" ),
array ( "id" => "978", "Name" => "Thor", "Franchise" => "Marvel", "Superpower" => "Inherent" ));
echo "<pre>";
$return = array();
// first group array values by franchise
foreach($a as $val) {
if (!isset($return[$val['Franchise']])) {
$return[$val['Franchise']] = array();
}
$return[$val['Franchise']][] = $val;
}
$arr = array();
// count elements by key value pair in particular franchise
foreach ($return as $key => $value) {
$tmp = array_count_values(array_column($value, 'Superpower'));
$arr[$key] = $tmp;
}
print_r($arr);
Demo is here

Answer 3

With single and short array_reduce:
// $arr is your initial array
$result = array_reduce($arr, function($r, $v){
if (isset($r[$v["Franchise"]][$v["Superpower"]])) {
$r[$v["Franchise"]][$v["Superpower"]] += $r[$v["Franchise"]][$v["Superpower"]];
} else {
$r[$v["Franchise"]][$v["Superpower"]] = 1;
}
return $r;
}, []);
print_r($result);
The output:
Array
(
[DC Comics] => Array
(
[Inherent] => 1
[Acquired] => 1
)
[Marvel] => Array
(
[Acquired] => 2
[Inherent] => 1
)
)