Data catalog objects

Data catalogs are the key data structures in yet_another_wizz and provide a unified interface to object catalogs used for correlation measurements. In fact the correlation measurement itself is implemented as a method of the catalog base class BaseCatalog, but more on that in the next section.

>>> factory = yaw.NewCatalog()

>>> cat = factory.from_file(
...     "reference.fits", ra="ra", dec="dec", redshift="z", patches=32)
>>> cat
ScipyCatalog(loaded=True, nobjects=389596, npatches=32, redshifts=True)