Arranging array in php - php

Question

my problem is i can't arrange the array in the structure i want.
array1 and array2 are generated dynamically. as you can see in the array 2 it has a subjectid which is the same in array1, that means, that element is under the subject cpe 305. all elements in the array 2 which has the id of 5 is under the the subject of cpe 305. same logic with cpe 304.
array1:
Array
(
[0] => Array
(
[subjectid] => 5
[subjectcode] => Cpe 305
)
[1] => Array
(
[subjectid] => 4
[subjectcode] => Cpe 304
)
)
array2:
Array
(
[0] => Array
(
[subjectid] => 5
[soid] => 1
[socode] => A
[sodesc] => Ability to apply knowledge of mathematics and science to solve engineering problems
)
[1] => Array
(
[subjectid] => 5
[soid] => 3
[socode] => C
[sodesc] => Ability to design a system, component, or process to meet the desired needs within realistic constraints such as economic, environmental, social, political, ethical, health and safety, manufacturability, and sustainability, in accordance to standards
)
[2] => Array
(
[subjectid] => 5
[soid] => 4
[socode] => D
[sodesc] => Ability to function on multidisciplinary teams
)
[3] => Array
(
[subjectid] => 5
[soid] => 5
[socode] => E
[sodesc] => Ability to identify, formulate, and solve engineering problems
)
[4] => Array
(
[subjectid] => 5
[soid] => 9
[socode] => I
[sodesc] => Recognition of the need for, and an ability to engage in life-long learning
)
[5] => Array
(
[subjectid] => 4
[soid] => 10
[socode] => J
[sodesc] => Knowledge of contemporary issues
)
)
OUTPUT (my desired structure)
Array(
[subjectid] => 5
[subjectcode] => Cpe 305
[sodetails] => array(
[0]=>Array ([soid]=>1
[socode]=>A)
[1]=>Array([soid]=>3
[socode]=>C .....until the last
)
[subjectid] => 4
[subjectcode] => Cpe 305
[sodetails] => array(
[0]=>Array ([soid]=>10
[socode]=>J)
.......until the last
)
what i've tried
this is the code that im testing. i only include few data here in my test code.
$so = array();
$exist = array();
foreach ($this->subject as $key => $value) {
foreach ($this->sodetails as $key2 => $value2) {
if($value['subjectid'] === $value2['subjectid']){
$exist = array(
"subjectid" => $value['subjectid'],
"details" =>array(
"soid" => $value2['soid']
)
);
array_push($so, $exist);
}
}
}

Answer 1

First of all your output array is incorrect. An array cannot have more than one same indexes like "subjectid", "subjectcode". We need to have a different index. It will be wise to use subjectid as index for outer array.
First prepare your outer array as it is array1.
foreach($this->subject as $key => $val){
$myArray[$val['subjectid']]['subjectid'] => $val['subjectid'];
$myArray[$val['subjectid']]['subjectcode'] => $val['subjectcode'];
}
Now iterate your sodetails array.
foreach($this->sodetails as $key => $val){
$temp['soid'] = $val['soid'];
$temp['socode'] = $val['socode'];
array_push($myArray[$val['subjectid']]['sodetails'], $temp);
}
There can be other ways too. But it is my style and I believe it will solve your problem.

Answer 2

You just need to pass subjectid as key in your return array,
$exist = array();
foreach ($this->subject as $key => $value) {
foreach ($this->sodetails as $key2 => $value2) {
if($value['subjectid'] === $value2['subjectid']){
$exist[$value['subjectid']]['subjectid'] = $value['subjectid'];
$exist[$value['subjectid']]['subjectcode'] = $value['subjectcode'];
$exist[$value['subjectid']]['sodetails'] = array(array('soid'=>$value2['soid']),array('socode'=>$value2['socode']));
}
}
}

Answer 3

Instead of running the loop/iterations for m x n times, what you could do is first have the subjectid as the key for the $arrray1 and let the natural PHP array key handling do the job.
$new_array1 = array();
foreach($arrray1 as $item){
$new_array1[$item['subjectcode']] = $item;
}
foreach($array2 as $desc){
if(array_key_exists($desc['subjectid'],$new_array1){
$new_array1[$desc['subjectid']]['desc'][] = $desc;
}
}
This way you only have to make m + n iterations.