"""
AncestryShort functions
"""
#-----------------------------------------------------------------------------
# Copyright (c) ytree development team. All rights reserved.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file COPYING.txt, distributed with this software.
#-----------------------------------------------------------------------------
from yt.utilities.operator_registry import \
OperatorRegistry
ancestry_short_registry = OperatorRegistry()
[docs]def add_ancestry_short(name, function):
"""
Add an ancestry short-out function to the registry.
"""
ancestry_short_registry[name] = AncestryShort(function)
[docs]class AncestryShort(object):
r"""
An AncestryShort takes a halo and an ancestor halo and
determines if the ancestry search should come to an end.
Parameters
----------
halo: halo data container
Data container of the descendent halo.
ancestor : halo data container
Data container for the ancestor halo.
The function should return True or False.
"""
[docs] def __init__(self, function, args=None, kwargs=None):
self.function = function
self.args = args
if self.args is None: self.args = []
self.kwargs = kwargs
if self.kwargs is None: self.kwargs = {}
def __call__(self, halo, ancestor):
return self.function(halo, ancestor, *self.args, **self.kwargs)
[docs]def above_mass_fraction(halo, ancestor, fraction):
r"""
Return only the most massive ancestor.
Parameters
----------
halo: halo data container
Data container of the descendent halo.
ancestor : halo data container
Data containers for the ancestor halo.
Returns
-------
True or False
"""
return ancestor.mass > fraction * halo.mass
add_ancestry_short("above_mass_fraction", above_mass_fraction)