hex.tree

Class DTree

java.lang.Object

water.Iced

hex.tree.DTree

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Cloneable, water.Freezable

public class DTree
extends water.Iced

A Decision Tree, laid over a Frame of Vecs, and built distributed.

This class defines an explicit Tree structure, as a collection of DTree Nodes. The Nodes are numbered with a unique _nid. Users need to maintain their own mapping from their data to a _nid, where the obvious technique is to have a Vec of _nids (ints), one per each element of the data Vecs.

Each Node has a DHistogram, describing summary data about the rows. The DHistogram requires a pass over the data to be filled in, and we expect to fill in all rows for Nodes at the same depth at the same time. i.e., a single pass over the data will fill in all leaf Nodes' DHistograms at once.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DTree.DecidedNode
static class	DTree.LeafNode
static class	DTree.Node
static class	DTree.Split
static class	DTree.UndecidedNode

Field Summary

Fields

Modifier and Type	Field and Description
int	_depth
int	_leaves
int	_len
int	_min_rows

Constructor Summary

Constructors

Constructor and Description
DTree(java.lang.String[] names, int ncols, char nbins, char nbins_cats, char nclass, int min_rows)
DTree(java.lang.String[] names, int ncols, char nbins, char nbins_cats, char nclass, int min_rows, long seed)

Method Summary

Methods

Modifier and Type	Method and Description
CompressedTree	compress(int tid, int cls)
DTree.DecidedNode	decided(int i)
static boolean	isRootNode(DTree.Node n)
int	len()
DTree.Node	node(int i)
DTree.Node	root()
DTree.UndecidedNode	undecided(int i)

Methods inherited from class water.Iced

clone, frozenType, read_impl, read, readExternal, readJSON_impl, readJSON, toJsonString, write_impl, write, writeExternal, writeHTML_impl, writeHTML, writeJSON_impl, writeJSON

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_min_rows

public final int _min_rows

_len

public int _len

_leaves

public int _leaves

_depth

public int _depth

Constructor Detail

DTree

public DTree(java.lang.String[] names,
     int ncols,
     char nbins,
     char nbins_cats,
     char nclass,
     int min_rows)

DTree

public DTree(java.lang.String[] names,
     int ncols,
     char nbins,
     char nbins_cats,
     char nclass,
     int min_rows,
     long seed)

Method Detail

root

public final DTree.Node root()

node

public final DTree.Node node(int i)

undecided

public final DTree.UndecidedNode undecided(int i)

decided

public final DTree.DecidedNode decided(int i)

len

public final int len()

isRootNode

public static boolean isRootNode(DTree.Node n)

compress

public CompressedTree compress(int tid,
                      int cls)