Recreate Multidimensional Array in PHP - php

Question

This is pretty basic, but my question is:
Given an array:
$a = array(
0 => array('Rate'=> array('type_id'=>1, 'name' => 'Rate_1', 'type'=>'day','value'=>10)),
1 => array('Rate'=> array('type_id'=>1, 'name' => 'Rate_2', 'type'=>'night','value'=>8)),
2 => array('Rate'=> array('type_id'=>2, 'name' => 'Rate_3', 'type'=>'day','value'=>7)),
3 => array('Rate'=> array('type_id'=>2, 'name' => 'Rate_4', 'type'=>'nigh','value'=>16)),
4 => array('Rate'=> array('type_id'=>3, 'name' => 'Rate_5', 'type'=>'day','value'=>10))
);
What is the most efficient way to change it so we have something like:
$new_array = array(
[type_id] => array(
[type] => array(
[value]
)
)
)
);
In other words, I would like to strip some data (the name, which I don't need) and reorganise the dimensions of the array. In the end I would have an array which I would be able to access the values by $new_array['type_id']['type']['value'].

Answer 1

Not entirely sure if this is exactly what you want, but with this you can access the values by saying
echo $new[TYPE_ID][DAY_OR_NIGHT];
$new = array();
foreach($a AS $b){
$c = $b['Rate'];
$new[$c['type_id']][$c['type']] = $c['value'];
}
Using print_r on $new would give you:
Array
(
[1] => Array
(
[day] => 10
[night] => 8
)
[2] => Array
(
[day] => 7
[night] => 16
)
[3] => Array
(
[day] => 10
)
)

Answer 2

Since php 5.3.0, array_reduce() allows using an array as the initial value, given your initial array $a, you can use the following code
function my_reducer ($result, $item) {
$result[$item['Rate']['type_id']][$item['Rate']['type']] = $item['Rate']['value'];
return $result;
}
$assoc_arr = array_reduce($a, 'my_reducer', array());
var_dump($assoc_arr);
This returns
array(3) { [1]=> array(2) {
["day"]=>
int(10)
["night"]=>
int(8) } [2]=> array(2) {
["day"]=>
int(7)
["nigh"]=>
int(16) } [3]=> array(1) {
["day"]=>
int(10) } }