class ytree.data_structures.arbor.CatalogArbor(filename)[source]

Base class for Arbors created from a series of halo catalog files where the descendent ID for each halo has been pre-determined.

Unlike formats where tree information is stored in single file, halos are scattered about multiple catalog files. This requires us to store the root TreeNode objects and their full assemblies.


Initialize an Arbor given an input file.


__init__(filename) Initialize an Arbor given an input file.
add_alias_field(alias, field[, units, force_add]) Add a field as an alias to another field.
add_analysis_field(name, units[, dtype, default]) Add an empty field to be filled by analysis operations.
add_derived_field(name, function[, units, …]) Add a field that is a function of other fields.
add_vector_field(name) Add vector fields for a set of x,y,z component fields.
get_nodes_from_selection(*args, **kwargs)
get_yt_selection(*args, **kwargs)
is_grown(tree_node) Return True if a tree has been fully assembled, i.e., the hierarchy of ancestor tree nodes has been built.
is_setup(tree_node) Return True if arrays of uids and descendent uids have been read in.
query(key) If given a string, return an array of field values for the roots of all trees.
reset_node(tree_node) Reset all data structures for a single node.
save_arbor(**kwargs) Save the arbor to a file.
select_halos(criteria[, trees, select_from, …]) Select halos from the arbor based on a set of criteria given as a string.
set_selector(selector, *args, **kwargs) Sets the tree node selector to be used.


arr Create a unyt_array using the Arbor’s unit registry.
box_size The simulation box size.
field_info A dictionary containing information for each available field.
hubble_constant Value of the Hubble parameter.
is_planted Determine if trees have been planted.
quan Create a unyt_quantity using the Arbor’s unit registry.
size Return total number of trees.
unit_registry Unit system registry.