Populating Multi-Dimensional Array

Question

I'm playing around with multi-dimensional arrays. I'm trying to figure out how to populate an element/object of an array of an array of an array.

I simplified what I am ultimately trying to do with just an example on cars but this mimics the array structure I am going for minus more complexity.

Please excuse me if this is too obvious or stupid of a question.

It's returning an error and I can't populate: array_push() expects parameter 1 to be array, null given

If first parameter has to be an array, how can I populate an element of some array?

EDIT: I think I figured out that I can accomplish what I want by $arr[0][0][0] = 100; BUT not by array_push(); So my question and what I'm wondering now is what the heck array_push() is supposed to be used for?

<!-- Array
(
[0] => Array
    (
        [0] => Array // Brand (Mercedes)
            (
                [0] => 100 // Quantity
                [1] => 50000 // Price
                [2] => Germany // Nationality
                [3] => 1926 // Year Founded
                [4] => Mercedes
            )

        [1] => Array // Brand (BMW)
            (
                [0] => 200 // Quantity
                [1] => 20000 // Price
                [2] => Japan // Nationality
                [3] => 1933 // Year Founded
                [4] => Nissan
            )
    )

) -->

<?php

$arr = array(array(array()));


array_push($arr[0][0][0], 100);
array_push($arr[0][0][1], 50000);
array_push($arr[0][0][2], Germany);
array_push($arr[0][0][3], 1926);
array_push($arr[0][0][4], Mercedes);

array_push($arr[0][1][0], 200);
array_push($arr[0][1][1], 20000);
array_push($arr[0][1][2], Japan);
array_push($arr[0][1][3], 1933);
array_push($arr[0][1][4], Nissan);


echo "<pre>";
print_r($arr);

?>

From where you are getting this value....? – GYaN Jan 17 '18 at 05:30 — GYaN, Jan 17 '18 at 05:30

score 1 · Accepted Answer · 2018-01-17T05:22:55.313

1

You don't need array_push.

You just need this: $arr[0][0][0] = 100;

PHP doesn't have multi-dimensional arrays, it has arrays of arrays.

edited Jan 17 '18 at 05:22

answered Jan 17 '18 at 05:17

Thank you, I figured that out. But trying to figure out what array_push() is actually used for now...? – EGP Jan 17 '18 at 05:32
1

https://stackoverflow.com/questions/14232766/difference-between-array-push-and-array – Jan 17 '18 at 05:33
1

i just like to think php is "liberal" in their way of doing things. `array_push` will receive an an error while using `[]` will result in creation of a new dimension if need. – Jan 17 '18 at 05:36
1

while this is not related, try `echo "5$" + 1 ;`. – Jan 17 '18 at 05:37

Tommy Lee · Answer 2 · 2018-01-17T06:25:25.573

1

You may try this

<?php

$arr = [];


$arr[0][0][0] = 100;
$arr[0][0][1] = 50000;
$arr[0][0][2] = "Germany";
$arr[0][0][3] = 1926;
$arr[0][0][4] = "Mercedes";

$arr[0][1][0] = 200;
$arr[0][1][1] = 20000;
$arr[0][1][2] = "Japan";
$arr[0][1][3] = 1933;
$arr[0][1][4] = "Nissan";


?>

array_push works as $array[] = "a", but it is more used to push multiple values into an array.

If you use array_push() to add one element to the array it's better to use $array[] = because in that way there is no overhead of calling a function. quoted from php.net

edited Jan 17 '18 at 06:25

answered Jan 17 '18 at 05:18

Tommy Lee

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2
11
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Thank you, I figured that out. But trying to figure out what array_push() is actually used for now...? – EGP Jan 17 '18 at 05:32

Populating Multi-Dimensional Array

2 Answers2