smile.sort

Class IntHeapSelect

java.lang.Object

smile.sort.IntHeapSelect

public class IntHeapSelect
extends Object

This class tracks the smallest values seen thus far in a stream of values. This implements a single-pass selection for large data sets. That is, we have a stream of input values, each of which we get to see only once. We want to be able to report at any time, say after n values, the i-th smallest value see so far.

Author:

Haifeng Li

Constructor Summary

Constructors

Constructor and Description
IntHeapSelect(int k) Constructor.
IntHeapSelect(int[] heap) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(int datum) Assimilate a new value from the stream.
int	get(int i) Returns the i-th smallest value seen so far.
int	peek() Returns the k-th smallest value seen so far.
void	sort() Sort the smallest values.

Methods inherited from class java.lang.Object

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

Constructor Detail

IntHeapSelect

public IntHeapSelect(int k)

Constructor.

Parameters:

k - the heap size.

IntHeapSelect

public IntHeapSelect(int[] heap)

Constructor.

Parameters:

heap - the array to store smallest values to track.

Method Detail

add

public void add(int datum)

Assimilate a new value from the stream.

peek

public int peek()

Returns the k-th smallest value seen so far.

get

public int get(int i)

Returns the i-th smallest value seen so far. i = 0 returns the smallest value seen, i = 1 the second largest, ..., i = k-1 the last position tracked. Also, i must be less than the number of previous assimilated.

sort

public void sort()

Sort the smallest values.