I think you want to subclass an ndarray here. It's a bit tricky to so,
but if you look in the wiki and these mailing list archives, you'll find
advise on how to do it.
-Chris
--
Christopher Barker, Ph.D.
Oceanographer
Emergency Response Division
NOAA/NOS/OR&R (206) 526-6959 voice
7600 Sand Point Way NE (206) 526-6329 fax
Seattle, WA 98115 (206) 526-6317 main reception
Chris.Barker@noaa.gov