xgboost::ObjFunction Class Reference

interface of objective function More...

#include <objective.h>

Collaboration diagram for xgboost::ObjFunction:

Public Member Functions
virtual	~ObjFunction ()=default
	virtual destructor More...
template<typename PairIter >
void	Configure (PairIter begin, PairIter end)
	set configuration from pair iterators. More...
virtual void	Configure (const std::vector< std::pair< std::string, std::string > > &args)=0
	Configure the objective with the specified parameters. More...
virtual void	GetGradient (const HostDeviceVector< bst_float > &preds, const MetaInfo &info, int iteration, HostDeviceVector< GradientPair > *out_gpair)=0
	Get gradient over each of predictions, given existing information. More...
virtual const char *	DefaultEvalMetric () const =0
virtual void	PredTransform (HostDeviceVector< bst_float > *io_preds)
	transform prediction values, this is only called when Prediction is called More...
virtual void	EvalTransform (HostDeviceVector< bst_float > *io_preds)
	transform prediction values, this is only called when Eval is called, usually it redirect to PredTransform More...
virtual bst_float	ProbToMargin (bst_float base_score) const
	transform probability value back to margin this is used to transform user-set base_score back to margin used by gradient boosting More...

Static Public Member Functions
static ObjFunction *	Create (const std::string &name)
	Create an objective function according to name. More...

Detailed Description

interface of objective function

Constructor & Destructor Documentation

~ObjFunction()

virtual xgboost::ObjFunction::~ObjFunction ( )

virtualdefault

virtual destructor

Member Function Documentation

Configure() [1/2]

template<typename PairIter >

void xgboost::ObjFunction::Configure ( PairIter  begin, PairIter  end  )

inline

set configuration from pair iterators.

Parameters

begin	The beginning iterator.
end	The end iterator.

Template Parameters

PairIter

iterator<std::pair<std::string, std::string> >

Configure() [2/2]

virtual void xgboost::ObjFunction::Configure ( const std::vector< std::pair< std::string, std::string > > &  args )

pure virtual

Configure the objective with the specified parameters.

Parameters

args	arguments to the objective function.

Create()

static ObjFunction* xgboost::ObjFunction::Create ( const std::string &  name )

static

Create an objective function according to name.

Parameters

name	Name of the objective.

DefaultEvalMetric()

virtual const char* xgboost::ObjFunction::DefaultEvalMetric ( ) const

pure virtual

Returns

the default evaluation metric for the objective

EvalTransform()

virtual void xgboost::ObjFunction::EvalTransform ( HostDeviceVector< bst_float > *  io_preds )

inlinevirtual

transform prediction values, this is only called when Eval is called, usually it redirect to PredTransform

Parameters

io_preds

prediction values, saves to this vector as well

GetGradient()

virtual void xgboost::ObjFunction::GetGradient ( const HostDeviceVector< bst_float > &  preds, const MetaInfo &  info, int  iteration, HostDeviceVector< GradientPair > *  out_gpair  )

pure virtual

Get gradient over each of predictions, given existing information.

Parameters

preds	prediction of current round
info	information about labels, weights, groups in rank
iteration	current iteration number.
out_gpair	output of get gradient, saves gradient and second order gradient in

PredTransform()

virtual void xgboost::ObjFunction::PredTransform ( HostDeviceVector< bst_float > *  io_preds )

inlinevirtual

transform prediction values, this is only called when Prediction is called

Parameters

io_preds

prediction values, saves to this vector as well

ProbToMargin()

virtual bst_float xgboost::ObjFunction::ProbToMargin ( bst_float  base_score ) const

inlinevirtual

transform probability value back to margin this is used to transform user-set base_score back to margin used by gradient boosting

Returns

transformed value

---

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

• /workspace/include/xgboost/objective.h