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<?php $data = array ( array ('subj_title' => 'A', 'value' => 0 ) , array ('subj_title' => 'B', 'value' => 30 ) , array ('subj_title' => 'C', 'value' => 6 ) , array ('subj_title' => 'C', 'value' => 8 ) , array ('subj_title' => 'C', 'value' => 5 ), array ('subj_title' => 'C', 'value' => 11 ) ); $result = array(); foreach($data as $key => $value){ $index = $value['subj_title']; if(!isset($result[$index])){ $result[$index]['subj_title'] = $value['subj_title']; $result[$index]['value'] = $value['value']; }else{ $result[$index]['value'] = $result[$index]['value'] + $value['value']; } } $result = array_values($result); echo '<pre>'; print_r($result);
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
<pre>Array ( [0] => Array ( [subj_title] => A [value] => 0 ) [1] => Array ( [subj_title] => B [value] => 30 ) [2] => Array ( [subj_title] => C [value] => 30 ) )

preferences:
148.32 ms | 408 KiB | 5 Q