php - Group ROWS in array with same Identifier -

how can run array below inside of foreach loop , group rows share same section_id?

i've labeled rows , sections comment blocks.

this array

array (      [0] => array ( // row 1         [assessment_selection_id] => 63          [assessment_id] => 32          [section_id] => 1 // section 1         [question_id] => 1          [selection] => 2          [timestamp] => 1368160586     )     [1] => array ( // row 2         [assessment_selection_id] => 61          [assessment_id] => 32          [section_id] => 2 // section 2         [question_id] => 1          [selection] => 3          [timestamp] => 1368160510     )    [2] => array ( // row 3         [assessment_selection_id] => 61          [assessment_id] => 32          [section_id] => 2 // section 2         [question_id] => 1          [selection] => 3          [timestamp] => 1368160510     )      [3] => array ( // row 4         [assessment_selection_id] => 61          [assessment_id] => 32          [section_id] => 2 // section 2         [question_id] => 1          [selection] => 3          [timestamp] => 1368160510     )  ) 

expected result

array (     [0] => array ( // section 1         [0] => array ( // row 1              [assessment_selection_id] => 63              [assessment_id] => 32              [section_id] => 1              [question_id] => 1              [selection] => 2              [timestamp] => 1368160586          )     )     [1] => array ( // section 2         [0] => array ( // row 1             [assessment_selection_id] => 61              [assessment_id] => 32              [section_id] => 2              [question_id] => 1              [selection] => 2              [timestamp] => 1368160586          )        [1] => array ( // row 2             [assessment_selection_id] => 61              [assessment_id] => 32              [section_id] => 2              [question_id] => 1              [selection] => 2              [timestamp] => 1368160586          )        [2] => array ( // row 3             [assessment_selection_id] => 61              [assessment_id] => 32              [section_id] => 2              [question_id] => 1              [selection] => 2              [timestamp] => 1368160586          )     ) ) 

expected result without array

section 1

• row 1

  assessment_selection_id, assessment_id, section_id, question_id, selection, timestamp

section 2

• row 1

  assessment_selection_id, assessment_id, section_id, question_id, selection, timestamp

• row 2

  assessment_selection_id, assessment_id, section_id, question_id, selection, timestamp

• row 3

  assessment_selection_id, assessment_id, section_id, question_id, selection, timestamp

let's think have array saved in $myarray this:

$newarray=array(); foreach($myarray $val){     $newkey=$val['section_id'];     $newarray[$newkey][]=$val } print_r($newarray);