从子数组的值相等的数组中删除元素

I have an array what consist of arrays. Have a looks into this file gist.
How you can see each array repeats two times. I need to delete the second, I need to compare them by 'key' value of array.
Thanks!

The undefined offset 6 error is telling you that there isnt an array element at position 6. Without seeing your error message and your code I cant tell you where the error is But you would need to see if the element exists using something like this:

if (isset($array[index]))
{
  //do something
}

This will handle the error, meaning you wont get the message, but you should see why the element doesnt exist, like Was there a problem when the arrays were made.

Your error message will tell you which line the problem was on and therefore which array variables are causing these errors.

UPDATE:

your code will always return true as you are comparing a value to itself therefore it will be an empty array.

$transll['key'] == $transll['key']

The easiest way to get the result you expect is in my opinion this way:

$data = array(
    array(
        'domain' => 'messages',
        'key' => 'test.testik',
        'message' => array()
    ),
    array(
        'domain' => 'messages',
        'key' => 'test2313.tes31231tik',
        'message' => array()
    ),
    array(
        'domain' => 'validators',
        'key' => 'valid.validik',
        'message' => array()
    ),
    array(
        'domain' => 'validators',
        'key' => 'joga.jimbo',
        'message' => array()
    ),
    array(
        'domain' => 'validators',
        'key' => 'valid.validik',
        'message' => array()
    )
);
$newdata = array();

foreach ($data as $subdata) {
    $newdata[$subdata['key']] = $subdata;
}

$newdata = array_values($newdata); // reset array indizes 

print_r($newdata);