NEIGHBOR SEARCHING APPARATUS
To provide a neighbor searching apparatus that can select an index suitable for each search target. A neighbor searching apparatus has: a storage part that stores a meta table containing index-dependent meta data associated with a data structure of each index; a database managing part that searches for an index associated with an instruction when receiving the instruction from a user and makes an indexing part perform a processing associated with the instruction using the index-dependent meta data associated with the index; and the indexing part that performs the processing associated with the instruction using the index-dependent meta data based on the instruction from the managing database part.
1 . A neighbor searching apparatus, comprising:
a storage unit that stores a meta table containing index-dependent meta data associated with a data structure of each index;
a database unit that searches for an index associated with an instruction when receiving the instruction from a user, and makes an indexing unit perform a processing associated with the instruction using the index-dependent meta data associated with the index; and
the indexing unit that performs the processing associated with the instruction using the index-dependent meta data based on the instruction from the database unit.
2 . A neighbor searching apparatus that searches for point data that exists in the proximity of a specified query point, wherein a search region for the query point is determined depending on the number of subordinate points of each node in such a manner that a search range for a node having a larger number of subordinate points is smaller than a search range for a node having a smaller number of subordinate points.
3 . The apparatus according to claim 2 , wherein a radius r that determines the search region is calculated according to the following formula:
r =(provisional k in the course of searching−distance between neighbor bounding region and query)/(1+ε′) [Expression 1]
and a coefficient ε′ in the formula that determines the radius r is calculated according to the following formula:
ɛ
′
=
min
(
ɛ
,
max
(
0
,
γɛ
log
(
number
of
subordinate
points
of
node
)
log
(
number
of
subordinate
points
of
whole
tree
)
)
)
[
Expression
2
]
(where γ and ε each represent an arbitrary constant).