Removing duplicates from multidimensional array based on the first elements only PHP - php

Question

This is the array
Array
(
[0] => Array
(
[artist] => John Keys
[postID] => 254
)
[1] => Array
(
[artist] => Jay Bloom
[postID] => 249
)
[2] => Array
(
[artist] => John Keys
[postID] => 216
)
[3] => Array
(
[artist] => Angie Belle
[postID] => 225
)
)
and I want to remove all duplicates from the artist elements only. Notice that 0 and 2 have the same artist but a different postID. I just want to keep the first occurence of the artist and remove all others. So the result I want to have is
Array
(
[0] => Array
(
[artist] => John Keys
[postID] => 254
)
[1] => Array
(
[artist] => Jay Bloom
[postID] => 249
)
[2] => Array
(
[artist] => Angie Belle
[postID] => 225
)
)
I've tried array_unique and also serializing and doing an array_map, nothing seems to work right.

Answer 1

<?php
$array = Array
(
'0' => Array
(
'artist' => 'John Keys',
'postID' => 254
),
'1' => Array
(
'artist' => 'Jay Bloom',
'postID' => 249
),
'2' => Array
(
'artist' => 'John Keys',
'postID' => 216
),
'3' => Array
(
'artist' => 'Angie Belle',
'postID' => 225
)
);
$newarray = array();
foreach($array as $key => $val){
if(!array_key_exists('artist', $newarray)){
$newarray[$val['artist']] = $val;
}
}
echo '<pre>';
print_r($newarray);
Edit: using numeric keys:
$newarray = array();
$temp = array();
foreach($array as $key => $val){
if(!in_array($val['artist'], $temp)){
$temp[] = $val['artist'];
}
if( !array_key_exists(array_search($val['artist'], $temp), $newarray) ){
$newarray[array_search($val['artist'], $temp)] = $val;
}
}

Answer 2

Simple approach:
$result = array();
foreach ($input as $item) {
if (!array_key_exists($item['artist'], $result)) {
$result[$item['artist']] = $item;
}
}

Answer 3

<?php
$a=array(
"0" => array
(
"artist" => "John Keys",
"postID" => "254"
),
"1" => array
(
"artist" => "Jay Bloom",
"postID" => "249"
),
"2" => array
(
"artist" => "John Keys",
"postID" => "216"
),
"3" => array
(
"artist" => "Angie Belle",
"postID" => "225"
)
);
var_dump($a);
for($i=0;$i<count($a);$i++)
{
for($j=$i+1;$j<count($a); $j++)
{
$tmp1=$a[$i]["artist"];
$tmp2=$a[$j]["artist"];
if($tmp1==$tmp2)
{
unset($a[$j]);
}
$tmp3=array_values($a);
$a=$tmp3;
}
}
var_dump($a);
?>