swiftgalaxy.masks module

class swiftgalaxy.masks.MaskCollection(**kwargs)

Bases: object

Barebones container for mask objects.

Takes a set of kwargs at initialisation and assigns their values to attributes of the object. Attempts to access a non-existent attribute returns None instead of raising an AttributeError.

This is intended to hold masks that can be applied to cosmo_array objects under the names of particle types (e.g. gas, dark_matter, etc.), but this is not checked or enforced.

Parameters:

**kwargs – Any items passed as kwargs will have their values passed to correspondingly named attributes of this object.

Notes

Note

The velociraptor.swift.swift module makes some use of a namedtuple called MaskCollection. These objects are not valid where swiftgalaxy functions expect a MaskCollection because namedtuple objects are immutable.

Examples

n_dm = 123  # suppose this is number of dark matter particles
# all these masks select all particles:
MaskCollection(
    gas=np.s_[...],
    dark_matter=np.ones(n_dm, dtype=bool),
    stars=None
)