Group associative array elements by values and preserve original keys as new values in each group

Question

I want to be able to group Associative Arrays with their `keys. So far I'm lost of what syntax to use.

As of now, I have thus code,

$associativeArray = array("Ripe Mango"=>"Yellow", "Strawberry"=>"Red", "Lemon"=>"Yellow");
groupByColor($associativeArray);

function groupByColor($groupedArray)
{
  return $groupedArray;
}

My goal is to return the array while having it grouped, the ideal result will be like this;

["Yellow"=>["Ripe Mango", "Lemon"], "Red"=>["Strawberry"]]

Any hints on what method to use?

Answer 1

Inside function do foreach()

<?php

$associativeArray = array("Ripe Mango" => "Yellow", "Strawberry" => "Red", "Lemon" => "Yellow");

function groupByColor($associativeArray) {
    $final_array = [];
    foreach ($associativeArray as $key => $val) {
        $final_array[$val][] = $key;
    }
    
    return $final_array;  
}
print_r(groupByColor($associativeArray));

Note:- you can assign groupByColor($associativeArray) returned array to a new variable and print that variable like below:-

$color_array = groupByColor($associativeArray);
print_r($color_array);