Delete characters from array

Hi,

I have an array, which I get from mysql. It looks about like this:
[yes,yes,-,no,yes,yes-,yes,no,yes,yes,-,…]
Now I want to delete all items which are a minus (-). How can I do that?
Array should contain at the and only yes and no.

Thank you

Das ist ein deutsches Forum…
http://php.net/manual/en/function.array-filter.php