On 3/6/11 5:54 AM, Charles R Harris wrote: > I suppose this might cause a problem with lazy/quick c extensions that > expected elements in a certain order, so some breakage could occur.
absolutely! (I've gotten a bit confused about this thread, but if this is about the question of whether structured dtypes are dtypes are assumed to always keep order, read on -- otherwise, ignore).. I have always assumed a structured dtype was much like a C struct: i.e. arrangement in memory is fixed, and the named fields are just for convenience. I was very surprised to learn that they could ever be used in more a a dict-like manner. Also, I noted a recent post to this list suggesting that folks sometime miss-use stuctured arrays (particularly folks coming from MATLAB, etc), by using them when what they really want is a dict. In that post, the poster suggested that the primary use of structured arrays was for interacting with data files and C code that has arrays of structures, and indeed, that is how I have primarily used them. So I think for performance and consistency with C code, keeping dtype order is the best way to go. If that breaks backward compatibility too much, then it shouldn't be changed, but I think it better reflects what dtypes are all about. -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 [email protected] _______________________________________________ NumPy-Discussion mailing list [email protected] http://mail.scipy.org/mailman/listinfo/numpy-discussion
