VantagePointSplit< BoundType, MatType, MaxNumSamples > Class Template Reference

The class splits a binary space partitioning tree node according to the median distance to the vantage point. More...

Classes

struct  SplitInfo
 A struct that contains an information about the split. More...

 

Public Types

typedef MatType::elem_type ElemType
 The matrix element type. More...

 
typedef BoundType::MetricType MetricType
 The bounding shape type. More...

 

Static Public Member Functions

template
<
typename
VecType
>
static bool AssignToLeftNode (const VecType &point, const SplitInfo &splitInfo)
 Indicates that a point should be assigned to the left subtree. More...

 
static size_t PerformSplit (MatType &data, const size_t begin, const size_t count, const SplitInfo &splitInfo)
 Perform the split process according to the information about the split. More...

 
static size_t PerformSplit (MatType &data, const size_t begin, const size_t count, const SplitInfo &splitInfo, std::vector< size_t > &oldFromNew)
 Perform the split process according to the information about the split and return the list of changed indices. More...

 
static bool SplitNode (const BoundType &bound, MatType &data, const size_t begin, const size_t count, SplitInfo &splitInfo)
 Split the node according to the distance to a vantage point. More...

 

Detailed Description


template<typename BoundType, typename MatType = arma::mat, size_t MaxNumSamples = 100>
class mlpack::tree::VantagePointSplit< BoundType, MatType, MaxNumSamples >

The class splits a binary space partitioning tree node according to the median distance to the vantage point.

Thus points that are closer to the vantage point belong to the left subtree and points that are farther from the vantage point belong to the right subtree.

Definition at line 32 of file vantage_point_split.hpp.

Member Typedef Documentation

◆ ElemType

typedef MatType::elem_type ElemType

The matrix element type.

Definition at line 36 of file vantage_point_split.hpp.

◆ MetricType

typedef BoundType::MetricType MetricType

The bounding shape type.

Definition at line 38 of file vantage_point_split.hpp.

Member Function Documentation

◆ AssignToLeftNode()

static bool AssignToLeftNode ( const VecType &  point,
const SplitInfo splitInfo 
)
inlinestatic

Indicates that a point should be assigned to the left subtree.

This method returns true if a point should be assigned to the left subtree, i.e., if the distance from the point to the vantage point is less then the median value. Otherwise it returns false.

Parameters
pointThe point that is being assigned.
splitInfoAn information about the split.

Definition at line 138 of file vantage_point_split.hpp.

References VantagePointSplit< BoundType, MatType, MaxNumSamples >::SplitInfo::metric, VantagePointSplit< BoundType, MatType, MaxNumSamples >::SplitInfo::mu, and VantagePointSplit< BoundType, MatType, MaxNumSamples >::SplitInfo::vantagePoint.

◆ PerformSplit() [1/2]

static size_t PerformSplit ( MatType &  data,
const size_t  begin,
const size_t  count,
const SplitInfo splitInfo 
)
inlinestatic

Perform the split process according to the information about the split.

This will order the dataset such that points that belong to the left subtree are on the left of the split column, and points from the right subtree are on the right side of the split column.

Parameters
boundThe bound used for this node.
dataThe dataset used by the binary space tree.
beginIndex of the starting point in the dataset that belongs to this node.
countNumber of points in this node.
splitInfoThe information about the split.

Definition at line 93 of file vantage_point_split.hpp.

◆ PerformSplit() [2/2]

static size_t PerformSplit ( MatType &  data,
const size_t  begin,
const size_t  count,
const SplitInfo splitInfo,
std::vector< size_t > &  oldFromNew 
)
inlinestatic

Perform the split process according to the information about the split and return the list of changed indices.

This will order the dataset such that points that belong to the left subtree are on the left of the split column, and points from the right subtree are on the right side of the split column.

Parameters
boundThe bound used for this node.
dataThe dataset used by the binary space tree.
beginIndex of the starting point in the dataset that belongs to this node.
countNumber of points in this node.
splitInfoThe information about the split.
oldFromNewVector which will be filled with the old positions for each new point.

Definition at line 118 of file vantage_point_split.hpp.

◆ SplitNode()

static bool SplitNode ( const BoundType &  bound,
MatType &  data,
const size_t  begin,
const size_t  count,
SplitInfo splitInfo 
)
static

Split the node according to the distance to a vantage point.

Parameters
boundThe bound used for this node.
dataThe dataset used by the binary space tree.
beginIndex of the starting point in the dataset that belongs to this node.
countNumber of points in this node.
splitInfoAn information about the split. This information contains the vantage point and the median distance to the vantage point.

Referenced by VantagePointSplit< BoundType, MatType, MaxNumSamples >::SplitInfo::SplitInfo().


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