How to remove duplicates in collection?

Question

I have collection in Laravel:

Collection {#450 ▼   #items: array:2 [▼     0 => Announcement {#533 ▶}     1 => Announcement {#553 ▶}   ] } 

It is the same items. How ti delete one of them?

Full code is:

public function announcements()     {          $announcements = $this->categories_ann->map(function ($c) {             return $c->announcements->map(function ($a) {                 $a->subsribed = true;                  return $a;             });         });          $flattened = $announcements->groupBy("id")->flatten();          return $flattened;     } 

Answer 1

$unique = $collection->unique(); 

Answer 2

$collection = collect([     ['name' => 'iPhone 6', 'brand' => 'Apple', 'type' => 'phone'],     ['name' => 'iPhone 5', 'brand' => 'Apple', 'type' => 'phone'],     ['name' => 'Apple Watch', 'brand' => 'Apple', 'type' => 'watch'],     ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'],     ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watch'], ]); 

Then let's say you want the brand to be unique, in this case you should only get two brands 'Apple', and 'Samsung'

$unique = $collection->unique('brand');  $unique->values()->all(); /*     [         ['name' => 'iPhone 6', 'brand' => 'Apple', 'type' => 'phone'],         ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'],     ] */ 

This is taken from https://laravel.com/docs/master/collections#method-unique