If what you mean is to remove all duplicates then there is a good implementation of it included in the array part of the openG toolkit which you can download at http://prdownloads.sourceforge.net/opengtoolkit/array-6.0.1.1.zip?download
The toolkit has lots of other useful functions though so you might want to download the whole kit, in that case it's:
http://prdownloads.sourceforge.net/opengtoolkit/all_packages_ogtk-1.1.zip?download
Mads