fill in the multidimensional array with missing keys - php

Question

I have the following multidimensional array. I had to create keys the way it looks to group them accordingly.
Array
(
[Oranges] => Array
(
[Name] => Oranges
[l.VA123] => 17
[l.MA123] => 12
[l.GA123] => 9
[l.CT123] => 5
)
[Apple] => Array
(
[Name] => Apple
[l.CA123] => 13
)
[Grapes] => Array
(
[Name] => Grapes
[l.WI123] => 8
[l.FL123] => 5
)
)
However, I need all the subarrays to have the same keys. Missing ones should be filled with a value of 0. The final array should be like below so that all subarrays have equal length.
Array
(
[Oranges] => Array
(
[Name] => Oranges
[l.VA123] => 17
[l.MA123] => 12
[l.GA123] => 9
[l.CT123] => 5
[l.CA123] => 0
[l.WI123] => 0
[l.FL123] => 0
)
[Apple] => Array
(
[Name] => Apple
[l.CA123] => 13
[l.WI123] => 0
[l.FL123] => 0
[l.VA123] => 0
[l.MA123] => 0
[l.GA123] => 0
[l.CT123] => 0
)
[Grapes] => Array
(
[Name] => Grapes
[l.WI123] => 8
[l.FL123] => 5
[l.CA123] => 0
[l.VA123] => 0
[l.MA123] => 0
[l.GA123] => 0
[l.CT123] => 0
)
)

Answer 1

You need a simple + operator. As from manual:
The + operator returns the right-hand array appended to the left-hand array; for keys that exist in both arrays, the elements from the left-hand array will be used, and the matching elements from the right-hand array will be ignored.
$items = Array
(
'Oranges' => Array
(
'Name' => 'Oranges',
'l.VA123' => 17,
'l.MA123' => 12,
'l.GA123' => 9,
'l.CT123' => 5,
),
'Apple' => Array
(
'Name' => 'Apple',
'l.CA123' => 13,
),
'Grapes' => Array
(
'Name' => 'Grapes',
'l.WI123' => 8,
'l.FL123' => 5,
),
);
// static keys
$keys = [
'l.VA123' => 0,
'l.MA123' => 0,
'l.GA123' => 0,
'l.CT123' => 0,
'l.CA123' => 0,
'l.WI123' => 0,
'l.FL123' => 0,
];
// keys generated from source array, tricky approach
$keys = array_fill_keys(
// here we merge all elements of `$items` into one array
// as keys are repeated - you definitely got all keys that
// can be in `$items`, `array_keys` will give you these keys
// `array_fill_keys` will create array where key is what you need
// and value is 0.
array_keys(call_user_func_array('array_merge', $items)),
0
);
// keys generated from source array, SIMPLE approach
$keys = [];
foreach ($items as $item) {
foreach ($item as $k => $v) {
if ($k != 'Name') {
$keys[$k] = 0;
}
}
}
foreach ($items as &$item) {
$item = $item + $keys;
}
print_r($items);

Answer 2

Probably someone can come up with something more efficient, but without a list of keys that you want, I think you'll need to take a couple of passes of the array:
<?php
$fruits = [
"Oranges"=>["Name"=>"Oranges", "l.VA123"=>17, "l.MA123"=>12, "1.GA123"=>9, "1.CT123"=>5],
"Apple"=>["Name"=>"Apple", "1.CA123"=>13],
"Grapes"=>["Name"=>"Grapes", "1.WI123"=>8, "1.FL123"=>5]
];
$keys = [];
foreach ($fruits as $fruit) {
unset($fruit["Name"]);
$keys = array_merge($keys, array_keys($fruit));
}
$keys = array_fill_keys(array_unique($keys), 0);
foreach ($fruits as &$fruit) {
$fruit = array_merge($keys, $fruit);
}
print_r($fruits);

Answer 3

Since all keys and default values are "known", create an associative array, use a foreach() and modify the rows by reference, and use the union-assignment (combined) operator. This will allow the original values to overwrite the default values.
Code: (Demo)
$keys = [
'l.VA123' => 0,
'l.MA123' => 0,
'l.GA123' => 0,
'l.CT123' => 0,
'l.CA123' => 0,
'l.WI123' => 0,
'l.FL123' => 0,
];
foreach ($items as &$row) {
$row += $keys;
}
var_export($items);
If you want the keys to be consistently positioned, then use array_replace() or array_merge() instead of the union assignment operator.
Code: (Demo)
foreach ($items as &$row) {
$row = array_replace($keys, $row);
}