xgboost::MultiTargetTree Class Reference

Tree structure for multi-target model. More...

#include <multi_target_tree_model.h>

Inheritance diagram for xgboost::MultiTargetTree:

Collaboration diagram for xgboost::MultiTargetTree:

Public Member Functions
	MultiTargetTree (TreeParam const *param)
	MultiTargetTree (MultiTargetTree const &that)
MultiTargetTree &	operator= (MultiTargetTree const &that)=delete
	MultiTargetTree (MultiTargetTree &&that)=delete
MultiTargetTree &	operator= (MultiTargetTree &&that)=delete
void	SetRoot (linalg::VectorView< float const > weight, float sum_hess)
	Set the weight and statistics for the root. More...
void	Expand (bst_node_t nidx, bst_feature_t split_idx, float split_cond, bool default_left, linalg::VectorView< float const > base_weight, linalg::VectorView< float const > left_weight, linalg::VectorView< float const > right_weight, float loss_chg, float sum_hess, float left_sum, float right_sum)
	Expand a leaf into split node. More...
void	SetLeaves (std::vector< bst_node_t > leaves, common::Span< float const > weights)
void	SetLeaves ()
	Copy base weight into leaf weight for a non-reduced multi-target tree. More...
bool	IsLeaf (bst_node_t nidx) const
bst_node_t	LeftChild (bst_node_t nidx) const
bst_node_t	RightChild (bst_node_t nidx) const
bst_target_t	NumTargets () const
	Number of targets (size of a leaf). More...
bst_target_t	NumSplitTargets () const
	Number of reduced targets. More...
auto	NumLeaves () const
std::size_t	Size () const
MultiTargetTree *	Copy (TreeParam const *param) const
common::Span< float const >	LeafWeights (DeviceOrd device) const
linalg::VectorView< float const >	LeafValue (bst_node_t nidx) const
void	LoadModel (Json const &in) override
	load the model from a JSON object More...
void	SaveModel (Json *out) const override
	saves the model config to a JSON object More...
std::size_t	MemCostBytes () const
Public Member Functions inherited from xgboost::Model
virtual	~Model ()=default

Static Public Member Functions
static constexpr bst_node_t	InvalidNodeId ()

Friends
struct	tree::MultiTargetTreeView

Detailed Description

Tree structure for multi-target model.

In order to support reduced gradient, the internal storage distinguishes weights between base weights and leaf weights. The former is the weight calculated from split gradient, and the later is the weight calculated from value gradient and used as outputs. Every node has a base weight, but only leaves have leaf weights.

To access the leaf weights, we re-use the right child to store leaf indices. For split nodes, the right_ member stores their right child node indices, for leaf nodes, the right_ member stores the corresponding leaf weight indices.

Constructor & Destructor Documentation

MultiTargetTree() [1/3]

xgboost::MultiTargetTree::MultiTargetTree ( TreeParam const *  param )

explicit

MultiTargetTree() [2/3]

xgboost::MultiTargetTree::MultiTargetTree

(

MultiTargetTree const &

that

)

MultiTargetTree() [3/3]

xgboost::MultiTargetTree::MultiTargetTree ( MultiTargetTree &&  that )

delete

Member Function Documentation

Copy()

MultiTargetTree* xgboost::MultiTargetTree::Copy

(

TreeParam const *

param

)

const

Expand()

void xgboost::MultiTargetTree::Expand	(	bst_node_t	nidx,
		bst_feature_t	split_idx,
		float	split_cond,
		bool	default_left,
		linalg::VectorView< float const >	base_weight,
		linalg::VectorView< float const >	left_weight,
		linalg::VectorView< float const >	right_weight,
		float	loss_chg,
		float	sum_hess,
		float	left_sum,
		float	right_sum
	)

Expand a leaf into split node.

InvalidNodeId()

static constexpr bst_node_t xgboost::MultiTargetTree::InvalidNodeId ( )

inlinestaticconstexpr

IsLeaf()

bool xgboost::MultiTargetTree::IsLeaf ( bst_node_t  nidx ) const

inline

LeafValue()

linalg::VectorView<float const> xgboost::MultiTargetTree::LeafValue ( bst_node_t  nidx ) const

inline

LeafWeights()

common::Span<float const> xgboost::MultiTargetTree::LeafWeights ( DeviceOrd  device ) const

inline

LeftChild()

bst_node_t xgboost::MultiTargetTree::LeftChild ( bst_node_t  nidx ) const

inline

LoadModel()

void xgboost::MultiTargetTree::LoadModel ( Json const &  in )

overridevirtual

load the model from a JSON object

Parameters

in	JSON object where to load the model from

Implements xgboost::Model.

MemCostBytes()

std::size_t xgboost::MultiTargetTree::MemCostBytes

(

)

const

NumLeaves()

auto xgboost::MultiTargetTree::NumLeaves ( ) const

inline

NumSplitTargets()

bst_target_t xgboost::MultiTargetTree::NumSplitTargets

(

)

const

Number of reduced targets.

NumTargets()

bst_target_t xgboost::MultiTargetTree::NumTargets

(

)

const

Number of targets (size of a leaf).

operator=() [1/2]

MultiTargetTree& xgboost::MultiTargetTree::operator= ( MultiTargetTree &&  that )

delete

operator=() [2/2]

MultiTargetTree& xgboost::MultiTargetTree::operator= ( MultiTargetTree const &  that )

delete

RightChild()

bst_node_t xgboost::MultiTargetTree::RightChild ( bst_node_t  nidx ) const

inline

SaveModel()

void xgboost::MultiTargetTree::SaveModel ( Json *  out ) const

overridevirtual

saves the model config to a JSON object

Parameters

out	JSON container where to save the model to

Implements xgboost::Model.

SetLeaves() [1/2]

void xgboost::MultiTargetTree::SetLeaves

(

)

Copy base weight into leaf weight for a non-reduced multi-target tree.

SetLeaves() [2/2]

void xgboost::MultiTargetTree::SetLeaves	(	std::vector< bst_node_t >	leaves,
		common::Span< float const >	weights
	)

See also

RegTree::SetLeaves

SetRoot()

void xgboost::MultiTargetTree::SetRoot	(	linalg::VectorView< float const >	weight,
		float	sum_hess
	)

Set the weight and statistics for the root.

Parameters

weight	The weight vector for the root node.
sum_hess	The sum of hessians for the root node (coverage).

Size()

std::size_t xgboost::MultiTargetTree::Size

(

)

const

Friends And Related Function Documentation

tree::MultiTargetTreeView

friend struct tree::MultiTargetTreeView

friend

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The documentation for this class was generated from the following file:

• /home/docs/checkouts/readthedocs.org/user_builds/xgboost/checkouts/latest/include/xgboost/multi_target_tree_model.h