org.apache.arrow.algorithm.rank

Class VectorRank<V extends ValueVector>

java.lang.Object

org.apache.arrow.algorithm.rank.VectorRank<V>

Type Parameters:

V - the vector type

public class VectorRank<V extends ValueVector>
extends Object

Utility for calculating ranks of vector elements.

Constructor Summary

Constructors

Constructor and Description
VectorRank(BufferAllocator allocator) Constructs a vector rank utility.

Method Summary

Modifier and Type	Method and Description
int	indexAtRank(V vector, VectorValueComparator<V> comparator, int rank) Given a rank r, gets the index of the element that is the rth smallest in the vector.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

VectorRank

public VectorRank(BufferAllocator allocator)

Constructs a vector rank utility.

Parameters:

allocator - the allocator to use.

Method Detail

indexAtRank

public int indexAtRank(V vector,
                       VectorValueComparator<V> comparator,
                       int rank)

Given a rank r, gets the index of the element that is the rth smallest in the vector. The operation is performed without changing the vector, and takes O(n) time, where n is the length of the vector.

Parameters:

vector - the vector from which to get the element index.

comparator - the criteria for vector element comparison.

rank - the rank to determine.

Returns:

the element index with the given rank.