Sept. 3, 2015
4:28 p.m.
From my perspective, a major advantage to dtypes is composability. For example, it's hard to write a library like dask.array (out of core arrays) that can suppose holding any conceivable ndarray subclass (like MaskedArray or quantity), but handling arbitrary dtypes is quite straightforward -- and that dtype information can be directly passed on, without the container library knowing anything about the library that implements the dtype.
Stephan