Getting values from array - php

Question

I know this is a newbie question,
I extracted some preformatted json out of javascript, that looks like this:
[[[455837.99,2896882.36],[455862.44,2896888.35],[455868.79,2896860.14],[455864.3,2896852.78],[455845.76,2896848],[455837.99,2896882.36]]]
I tried an online formatted that shows me the array looks something like this:
Array
(
[0] => Array
(
[0] => Array
(
[0] => 455837.99
[1] => 2896882.36
)
[1] => Array
(
[0] => 455862.44
[1] => 2896888.35
)
[2] => Array
(
[0] => 455868.79
[1] => 2896860.14
)
[3] => Array
(
[0] => 455864.3
[1] => 2896852.78
)
[4] => Array
(
[0] => 455845.76
[1] => 2896848
)
[5] => Array
(
[0] => 455837.99
[1] => 2896882.36
)
)
)
All the third [0]'s are what I need as an X, so everything that starts with 455. and All the [1]'s are the Y's. I would like these two to be grouped together, the respective X and Y.
My problem is I am not sure how to access them out of the area, I have tried this:
preg_match_all('/\[{3}.*\]{3}/', $data, $matches);
$arr=array();
foreach ($matches[0] as $match)
{
$arr[]=json_decode($match);
}
echo '<br>';
$newmatch = json_decode($match);
I would really appreciate if someone can point me in the direction of being able to have a loop that basically echo's the X and Y values, whenever I try and echo something from the array I get:
1) Array to string conversion
I am not sure if that is because of the triple brackets, that its an array in an array in an array.

Answer 1

$data = "[[[455837.99,2896882.36],[455862.44,2896888.35],[455868.79,2896860.14],[455864.3,2896852.78],[455845.76,2896848],[455837.99,2896882.36]]]";
$data_array = json_decode($data);
if (is_array($data_array) && array_key_exists(0, $data_array)) {
foreach ($data_array[0] as $element) {
$x = array_key_exists(0, $element) ? $element[0] : "N/A";
$y = array_key_exists(1, $element) ? $element[1] : "N/A";
printf("X: %s | Y: %s\n", $x, $y);
}
}