On Friday, June 10, 2016, Brian O'Shea <firstname.lastname@example.org> wrote:
I'm not sure, offhand. Probably very hard if you want to use the eval-style way of contrusting the data objects using a string written in Python, since data selection happens at a lower level in yt now. See selection_routines.pyx for more details about how this works.
It is possible to combine data objects by chaining data_source keyword arguments, (e.g. one can create a half-sphere data object by chaining a region that selects only half a sphere with a sphere data object). It may be possible to generalize that somehow.