API Reference

Working with Merger Trees

The load can load all supported merger tree formats. Once loaded, the save_arbor and save_tree functions can be used to save the entire arbor or individual trees.

load(filename[, method])	Load an Arbor, determine the type automatically.
Arbor(filename)	Base class for all Arbor classes.
add_alias_field(alias, field[, units, force_add])	Add a field as an alias to another field.
add_analysis_field(name, units)	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.
save_arbor([filename, fields, trees, …])	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.
save_tree([filename, fields])	Save the tree to a file.
set_selector(selector, *args, **kwargs)	Sets the tree node selector to be used.
TreeNodeSelector(function[, args, kwargs])	The TreeNodeSelector is responsible for choosing which one of a halo’s ancestors to return when querying the line of main progenitors for a halo.
add_tree_node_selector(name, function)	Add a TreeNodeSelector to the registry of known selectors, so they can be chosen with set_selector.
max_field_value(ancestors, field)	Return the TreeNode with the maximum value of the given field.
min_field_value(ancestors, field)	Return the TreeNode with the minimum value of the given field.

Visualizing Merger Trees

Functionality for plotting merger trees.

TreePlot(tree[, dot_kwargs])	Make a simple merger tree plot using pydot and graphviz.
save([filename])	Save the merger tree plot.

Internal Classes

Arbor(filename)	Base class for all Arbor classes.
CatalogArbor(filename)	Base class for Arbors created from a series of halo catalog files where the descendent ID for each halo has been pre-determined.
FieldInfoContainer(arbor)	A container for information about fields.
FieldContainer(arbor)	A container for field data.
FakeFieldContainer(arbor[, name])	A fake field data container used to calculate dependencies.
FieldIO(arbor)	Base class for FieldIO classes.
TreeFieldIO(arbor)	IO class for getting fields for a tree.
DefaultRootFieldIO(arbor)	Class for getting root fields from arbors that have no specialized storage for root fields.
DataFile(filename)	Base class for data files.
CatalogDataFile(filename, arbor)	Base class for halo catalog files.
TreeNode(uid[, arbor, root])	Class for objects stored in Arbors.
TreeNodeSelector(function[, args, kwargs])	The TreeNodeSelector is responsible for choosing which one of a halo’s ancestors to return when querying the line of main progenitors for a halo.
AHFArbor(filename[, hubble_constant])	Arbor for Amiga Halo Finder data.
AHFFieldInfo(arbor)
AHFDataFile(filename, arbor)
ArborArbor(filename)	Class for Arbors created with ytree version 1.1.0 or earlier.
ArborArborFieldInfo(arbor)
ArborArborTreeFieldIO(arbor)
ArborArborRootFieldIO(arbor)
ConsistentTreesArbor(filename)	Arbors from consistent-trees output files.
ConsistentTreesFieldInfo(arbor)
ConsistentTreesDataFile(filename)
ConsistentTreesTreeFieldIO(arbor)
LHaloTreeArbor(*args, **kwargs)	Arbors for LHaloTree data.
LHaloTreeFieldInfo(arbor)
LHaloTreeTreeFieldIO(arbor)
LHaloTreeRootFieldIO(arbor)
RockstarArbor(filename)	Class for Arbors created from Rockstar out_*.list files.
RockstarFieldInfo(arbor)
RockstarDataFile(filename, arbor)
TreeFarmArbor(filename)	Class for Arbors created with TreeFarm.
TreeFarmFieldInfo(arbor)
TreeFarmDataFile(filename, arbor)
TreeFarmTreeFieldIO(arbor)
YTreeArbor(filename)	Class for Arbors created from the save_arbor or save_tree functions.
YTreeDataFile(filename)
YTreeTreeFieldIO(arbor)
YTreeRootFieldIO(arbor)