open3d::core::nns::NearestNeighborSearch Class Reference

A Class for nearest neighbor search. More...

#include <NearestNeighborSearch.h>

Public Member Functions
	NearestNeighborSearch (const Tensor &dataset_points, const Dtype &index_dtype=core::Int32)
	~NearestNeighborSearch ()
	NearestNeighborSearch (const NearestNeighborSearch &)=delete
NearestNeighborSearch &	operator= (const NearestNeighborSearch &)=delete
bool	KnnIndex ()
bool	MultiRadiusIndex ()
bool	FixedRadiusIndex (utility::optional< double > radius={})
bool	HybridIndex (utility::optional< double > radius={})
std::pair< Tensor, Tensor >	KnnSearch (const Tensor &query_points, int knn)
std::tuple< Tensor, Tensor, Tensor >	FixedRadiusSearch (const Tensor &query_points, double radius, bool sort=true)
std::tuple< Tensor, Tensor, Tensor >	MultiRadiusSearch (const Tensor &query_points, const Tensor &radii)
std::tuple< Tensor, Tensor, Tensor >	HybridSearch (const Tensor &query_points, const double radius, const int max_knn) const

Protected Attributes
std::unique_ptr< NanoFlannIndex >	nanoflann_index_
std::unique_ptr< nns::FixedRadiusIndex >	fixed_radius_index_
std::unique_ptr< nns::KnnIndex >	knn_index_
const Tensor	dataset_points_
const Dtype	index_dtype_

Detailed Description

A Class for nearest neighbor search.

Constructor & Destructor Documentation

NearestNeighborSearch() [1/2]

open3d::core::nns::NearestNeighborSearch::NearestNeighborSearch ( const Tensor &  dataset_points, const Dtype &  index_dtype = core::Int32  )

inline

Constructor.

Parameters

dataset_points

Dataset points for constructing search index. Must be 2D, with shape {n, d}. SYCL tensors are not yet supported.

~NearestNeighborSearch()

open3d::core::nns::NearestNeighborSearch::~NearestNeighborSearch

(

)

NearestNeighborSearch() [2/2]

open3d::core::nns::NearestNeighborSearch::NearestNeighborSearch ( const NearestNeighborSearch &  )

delete

Member Function Documentation

FixedRadiusIndex()

bool open3d::core::nns::NearestNeighborSearch::FixedRadiusIndex

(

utility::optional< double >

radius = {}

)

Set index for fixed-radius search.

Parameters

radius

optional radius parameter. required for gpu fixed radius index.

Returns

Returns true if building index success, otherwise false.

FixedRadiusSearch()

std::tuple< Tensor, Tensor, Tensor > open3d::core::nns::NearestNeighborSearch::FixedRadiusSearch	(	const Tensor &	query_points,
		double	radius,
		bool	sort = true
	)

Perform fixed radius search. All query points share the same radius.

Parameters

query_points	Data points for querying. Must be 2D, with shape {n, d}.
radius	Radius.
sort	Sort the results by distance. Default is True.

Returns

Tuple of Tensors, (indices, distances, num_neighbors):

• indices: Tensor of shape {total_number_of_neighbors,}, with dtype same as index_dtype_.
• distances: Tensor of shape {total_number_of_neighbors,}, same dtype with query_points. The distances are squared L2 distances.
• num_neighbors: Tensor of shape {n+1,}, with dtype Int64. The Tensor is a prefix sum of the number of neighbors for each query point.

HybridIndex()

bool open3d::core::nns::NearestNeighborSearch::HybridIndex

(

utility::optional< double >

radius = {}

)

Set index for hybrid search.

Returns

Returns true if building index success, otherwise false.

HybridSearch()

std::tuple< Tensor, Tensor, Tensor > open3d::core::nns::NearestNeighborSearch::HybridSearch	(	const Tensor &	query_points,
		const double	radius,
		const int	max_knn
	)		const

Perform hybrid search.

Parameters

query_points	Data points for querying. Must be 2D, with shape {n, d}.
radius	Radius.
max_knn	Maximum number of neighbor to search per query.

Returns

Tuple of Tensors, (indices, distances, counts):

• indices: Tensor of shape {n, knn}, with dtype same as index_dtype_.
• distances: Tensor of shape {n, knn}, with same dtype with query_points. The distances are squared L2 distances.
• counts: Counts of neighbour for each query points. [Tensor of shape {n}, with dtype same as index_dtype_].

KnnIndex()

bool open3d::core::nns::NearestNeighborSearch::KnnIndex

(

)

Set index for knn search.

Returns

Returns true if building index success, otherwise false.

KnnSearch()

std::pair< Tensor, Tensor > open3d::core::nns::NearestNeighborSearch::KnnSearch	(	const Tensor &	query_points,
		int	knn
	)

Perform knn search.

Parameters

query_points	Query points. Must be 2D, with shape {n, d}.
knn	Number of neighbors to search per query point.

Returns

Pair of Tensors, (indices, distances):

• indices: Tensor of shape {n, knn}, with dtype same as index_dtype_.
• distances: Tensor of shape {n, knn}, same dtype with query_points. The distances are squared L2 distances.

MultiRadiusIndex()

bool open3d::core::nns::NearestNeighborSearch::MultiRadiusIndex

(

)

Set index for multi-radius search.

Returns

Returns true if building index success, otherwise false.

MultiRadiusSearch()

std::tuple< Tensor, Tensor, Tensor > open3d::core::nns::NearestNeighborSearch::MultiRadiusSearch	(	const Tensor &	query_points,
		const Tensor &	radii
	)

Perform multi-radius search. Each query point has an independent radius.

Parameters

query_points	Query points. Must be 2D, with shape {n, d}.
radii	Radii of query points. Each query point has one radius. Must be 1D, with shape {n,}.

Returns

Tuple of Tensors, (indices,distances, num_neighbors):

• indices: Tensor of shape {total_number_of_neighbors,}, with dtype same as index_dtype_.
• distances: Tensor of shape {total_number_of_neighbors,}, same dtype with query_points. The distances are squared L2 distances.
• num_neighbors: Tensor of shape {n+1,}, with dtype Int64. The Tensor is a prefix sum of the number of neighbors for each query point.

operator=()

NearestNeighborSearch& open3d::core::nns::NearestNeighborSearch::operator= ( const NearestNeighborSearch &  )

delete

Field Documentation

dataset_points_

const Tensor open3d::core::nns::NearestNeighborSearch::dataset_points_

protected

fixed_radius_index_

std::unique_ptr<nns::FixedRadiusIndex> open3d::core::nns::NearestNeighborSearch::fixed_radius_index_

protected

index_dtype_

const Dtype open3d::core::nns::NearestNeighborSearch::index_dtype_

protected

knn_index_

std::unique_ptr<nns::KnnIndex> open3d::core::nns::NearestNeighborSearch::knn_index_

protected

nanoflann_index_

std::unique_ptr<NanoFlannIndex> open3d::core::nns::NearestNeighborSearch::nanoflann_index_

protected

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

• /root/Open3D/cpp/open3d/core/nns/NearestNeighborSearch.h
• /root/Open3D/cpp/open3d/core/nns/NearestNeighborSearch.cpp