File lift_function_peak.hpp

namespace seco

class IPeakLiftFunctionConfig

#include <lift_function_peak.hpp>

Defines an interface for all classes that allow to configure a lift function that monotonously increases until a certain number of labels, where the maximum lift is reached, and monotonously decreases afterwards.

Subclassed by seco::PeakLiftFunctionConfig

Public Functions

inline virtual ~IPeakLiftFunctionConfig()

virtual uint32 getPeakLabel() const = 0

Returns the number of labels for which the lift is maximal.

Returns:

The number of labels for which the lift is maximal or 0, if the average label cardinality is used

virtual IPeakLiftFunctionConfig &setPeakLabel(uint32 peakLabel) = 0

Sets the number of labels for which the lift should be maximal.

Parameters:

peakLabel – The number of labels for which the lift should be maximal. Must be at least 1 or 0, if the average label cardinality should be used

Returns:

A reference to an object of type IPeakLiftFunctionConfig that allows further configuration of the lift function

virtual float64 getMaxLift() const = 0

Returns the lift at the peak label.

Returns:

The lift at the peak label

virtual IPeakLiftFunctionConfig &setMaxLift(float64 maxLift) = 0

Sets the lift at the peak label.

Parameters:

maxLift – The lift at the peak label. Must be at least 1

Returns:

A reference to an object of type IPeakLiftFunctionConfig that allows further configuration of the lift function

virtual float64 getCurvature() const = 0

Returns the curvature of the lift function.

Returns:

The curvature of the lift function

virtual IPeakLiftFunctionConfig &setCurvature(float64 curvature) = 0

Sets the curvature of the lift function.

Parameters:

curvature – The curvature of the lift function. A greater value results in a steeper curvature, a smaller value results in a flatter curvature. Must be greater than 0

Returns:

A reference to an object of type IPeakLiftFunctionConfig that allows further configuration of the lift function

class PeakLiftFunctionConfig : public seco::ILiftFunctionConfig, public seco::IPeakLiftFunctionConfig

#include <lift_function_peak.hpp>

Allows to configure a lift function that monotonously increases until a certain number of labels, where the maximum lift is reached, and monotonously decreases afterwards.

Public Functions

PeakLiftFunctionConfig()

virtual uint32 getPeakLabel() const override

Returns the number of labels for which the lift is maximal.

Returns:

The number of labels for which the lift is maximal or 0, if the average label cardinality is used

virtual IPeakLiftFunctionConfig &setPeakLabel(uint32 peakLabel) override

Sets the number of labels for which the lift should be maximal.

Parameters:

peakLabel – The number of labels for which the lift should be maximal. Must be at least 1 or 0, if the average label cardinality should be used

Returns:

A reference to an object of type IPeakLiftFunctionConfig that allows further configuration of the lift function

virtual float64 getMaxLift() const override

Returns the lift at the peak label.

Returns:

The lift at the peak label

virtual IPeakLiftFunctionConfig &setMaxLift(float64 maxLift) override

Sets the lift at the peak label.

Parameters:

maxLift – The lift at the peak label. Must be at least 1

Returns:

A reference to an object of type IPeakLiftFunctionConfig that allows further configuration of the lift function

virtual float64 getCurvature() const override

Returns the curvature of the lift function.

Returns:

The curvature of the lift function

virtual IPeakLiftFunctionConfig &setCurvature(float64 curvature) override

Sets the curvature of the lift function.

Parameters:

curvature – The curvature of the lift function. A greater value results in a steeper curvature, a smaller value results in a flatter curvature. Must be greater than 0

Returns:

A reference to an object of type IPeakLiftFunctionConfig that allows further configuration of the lift function

virtual std::unique_ptr<ILiftFunctionFactory> createLiftFunctionFactory(const IRowWiseLabelMatrix &labelMatrix) const override

Creates and returns a new object of type ILiftFunctionFactory according to the specified configuration.

Parameters:

labelMatrix – A reference to an object of type IRowWiseLabelMatrix that provides row-wise access to the labels of the training examples

Returns:

An unique pointer to an object of type ILiftFunctionFactory that has been created

Private Members

uint32 peakLabel_

float64 maxLift_

float64 curvature_