I have the following two structured dtypes:

rotation (quaternion) = dtype([('s','f8'),('v','3f8')]) frame = dtype([('t','3f8'),('r',rotation)])

For various reasons, I usually store rotation arrays in a class Rotations deriving from ndarray, and frames in a class Frames deriving from ndarray.

Currently I am defining .s, .v, .t, and .r properties manually, and I'd like to switch to inheriting from recarray. However, the .r property should return an array of class Rotations. I.e.,

f = Frames(...) # f.dtype = frame r = f.r # r.dtype = rotation, type(r) = Rotations

Is there a clean way to tell recarray to adjust the type returned? It already has a bit of intelligence there, since it returns ndarray vs. recarray based on whether the returned dtype has fields.

The full code is here in case anyone is curious:

https://github.com/otherlab/core/blob/master/vector/Frame.py https://github.com/otherlab/core/blob/master/vector/Rotation.py

Thanks, Geoffrey