Tree object (Multivariate Analysis Toolbox for Matlab®)

A tree is a directed graph (digraph) for which each node (except for the root) has exactly one parent. There is no limit to the number of descendants of each node. This objects inherits from the parent object digraph.

Navigate to: General Description Class Structure Class Construction Class Functions

Each field can be accessed by the dot (.) operation, or by the GET function. The GET function can work on multiple instances simultaneously. Most fields, except for those that are Dependent, can be modified using the dot (.) operation, or by the SET function.

	Field	Description	Type	Default	Dedicated Get/Set Function
	parent	parent of each node	double vector	[]
	thd	Inherited from digraph. target-height-differences matrix	double matrix	[]
	name	Inherited from graph. name of object, should be short and used as identifier. This field will never be empty.	string	'unnamed'
	description	Inherited from graph. verbal description of the class content.	string	''
	source	Inherited from graph. verbal description of the source of information.	string	''
	type	Inherited from graph. type of graph.	string	'general graph'
	node_name	Inherited from graph. names of all nodes.	cell array of strings	{}	nodenames
	node_mass	Inherited from graph. mass of each node.	double vector	[]
	node_cfield	Inherited from graph. user-specific node customized fields.	cell array of values	{}
	node_cfield_name	Inherited from graph. names of node customized fields.	cell array of strings	{}
	weights	Inherited from graph. symmetric sparse weight matrix.	double matrix	[]
Dependent	no_nodes	Inherited from graph. number of nodes in the graph.	integer scalar	0	nonodes
Dependent	no_node_cfields	Inherited from graph. number of customized fields.	integer scalar	0
Dependent	no_edges	Inherited from graph. number of edges in the graph.	integer vector	0	noedges

Empty instance (scalar): an empty tree instance, with all fields initialized to their default values.; syntax: tr = tree;
Empty instance (matrix): an array of empty tree instances.; syntax: tr = tree(size,'size');
Copy constructor: one tree instance is copied into another.; syntax: tr_destination = tree(tr_origin);
Construction by field names: an instance is formed by directly providing field values. Any field which is not dependent is permitted.; syntax: tr = tree(field_name, field_value, ...);

Computations:

balance: computes the balance vector. Source: digraph.
dag2code: finds the DAG-code of a DAG. Source: digraph.
laplacian: computes the Laplacian of a graph. Source: graph.
vstruct: finds nodes that are center of a V-structure. Source: digraph.

Customized fields manipulations:

alloccfield: allocates a new customized field to a graph. Source: graph.
cfieldexist: finds whether a customized field exists in a graph. Source: graph.
cfieldnames: lists the customized fields in a GRAPH object. Source: graph.
getcfield: retrieves a customized field from a graph. Source: graph.
setcfield: sets values for a customized field of GRAPHs. Source: graph.

Display:

show: displays class content. Source: graph.

I/O functions:

dump: writes a DIGRAPH to disk. Source: digraph.

Information extraction:

ancestors: finds the sequence of ancestors of a specifed node.
descendants: finds all descandants of a specifed node.
iodegree: computes the in and out degrees of a digraph. Source: digraph.
iscyclic: finds whether a DIGRAPH is cyclic or not. Source: digraph.
lca: finds the last common ancestor of a list of nodes.
leaves: finds these nodes that are leaves.
leavesunder: lists the leaves that are descendants of a particular node.
nodeid: finds the IDs of a list of nodes. Source: graph.
parents: finds the parents of specific nodes. Source: digraph.
root: finds the root of the tree.

Maintenance:

verify: computes missing.

SET/GET functions:

get: get method
nodenames: retrieves the name of the nodes in the graph. Source: graph.
noedges: retrieves the number of edges in GRAPH objects. Source: graph.
nonodes: retrieves the number of nodes in GRAPH objects. Source: graph.
set: set method

Transformations:

order: orders the nodes in a tree.
prunesubtree: prunes a subtree.
subtree: isolates the subtree branching from a certain node.
swap: replaces the indices of two nodes.
updatesubtree: substitutes the fields of a subtree in the father tree.

Visualization:

eigenproj: computes the eigenprojection of a graph. Source: graph.
view: plots a DIGRAPH Source: digraph.