combine XML objects PHP

It's pretty straightforward, I have an array with a number of nodes of the same structure available as Simple XML objects (extracted from different XML documents). What's the easiest way to add them to a single XML document, so I can output the combined XML? I've searched, but I can't find a good solution.

Edit: Array looks like this, how do I combine these objects in one single XML object?

Array (
[0] => Array
    (
        [0] => SimpleXMLElement Object
            (
                [@attributes] => Array
                    (
                        [no] => 23432423
                        [type] => Array
                    )

                [id] => 40043030
                [title] => Cars
                [cinemadate] => 2011-07-06
                [changedate] => 2011-07-27T10:19:00
                [year] => 2011
                [length] => 112
                [genres] => SimpleXMLElement Object
                    (
                        [genre] => animatie
                    )


[1] => Array
    (
        [0] => SimpleXMLElement Object
            (
                [@attributes] => Array
                    (
                        [no] => 48050593
                        [type] => Array
                    )

                [id] => 1231676
                [title] => Arrietty
                [cinemadate] => 2011-07-0开发者_运维百科6
                [changedate] => 2011-06-21T10:39:00
                [genres] => SimpleXMLElement Object
                    (
                        [genre] => animatie
                    )

Iterate over the array and add the data to the existing simplexml object. You have not provided much information in your question how the array data looks like nor have you provided an example simplexml object / xml chunk, so there is not much more to say specifically.