de.lmu.ifi.dbs.elki.utilities.datastructures.heap

Class DoubleIntegerMinHeap

java.lang.Object

de.lmu.ifi.dbs.elki.utilities.datastructures.heap.DoubleIntegerMinHeap

All Implemented Interfaces:

DoubleIntegerHeap

public class DoubleIntegerMinHeap
extends Object
implements DoubleIntegerHeap

Binary heap for primitive types.

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private class	DoubleIntegerMinHeap.UnsortedIter Unsorted iterator - in heap order.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	size Current size of heap.
private static int	TWO_HEAP_INITIAL_SIZE Initial size of the 2-ary heap.
protected double[]	twoheap Base heap.
protected int[]	twovals Base heap values.

Constructor Summary

Constructors

Constructor and Description
DoubleIntegerMinHeap() Constructor, with default size.
DoubleIntegerMinHeap(int minsize) Constructor, with given minimum size.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(double o, int v) Add a key-value pair to the heap
void	add(double key, int val, int max) Add a key-value pair to the heap if it improves the top.
void	clear() Clear the heap contents.
private void	heapifyDown(double cur, int val) Invoke heapify-down for the root object.
private void	heapifyUp(int twopos, double cur, int val) Heapify-Up method for 2-ary heap.
boolean	isEmpty() Is the heap empty?
double	peekKey() Get the current top key
int	peekValue() Get the current top value
void	poll() Remove the first element
void	replaceTopElement(double reinsert, int val) Combined operation that removes the top element, and inserts a new element instead.
int	size() Query the size
String	toString()
DoubleIntegerMinHeap.UnsortedIter	unsortedIter() Get an unsorted iterator to inspect the heap.

Methods inherited from class java.lang.Object

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

Field Detail

twoheap

protected double[] twoheap

Base heap.

twovals

protected int[] twovals

Base heap values.

size

protected int size

Current size of heap.

TWO_HEAP_INITIAL_SIZE

private static final int TWO_HEAP_INITIAL_SIZE

Initial size of the 2-ary heap.

See Also:

Constant Field Values

Constructor Detail

DoubleIntegerMinHeap

public DoubleIntegerMinHeap()

Constructor, with default size.

DoubleIntegerMinHeap

public DoubleIntegerMinHeap(int minsize)

Constructor, with given minimum size.

Parameters:

minsize - Minimum size

Method Detail

clear

public void clear()

Description copied from interface: DoubleIntegerHeap

Clear the heap contents.

Specified by:

clear in interface DoubleIntegerHeap

size

public int size()

Description copied from interface: DoubleIntegerHeap

Query the size

Specified by:

size in interface DoubleIntegerHeap

Returns:

Size

isEmpty

public boolean isEmpty()

Description copied from interface: DoubleIntegerHeap

Is the heap empty?

Specified by:

isEmpty in interface DoubleIntegerHeap

Returns:

true when the size is 0.

add

public void add(double o,
       int v)

Description copied from interface: DoubleIntegerHeap

Add a key-value pair to the heap

Specified by:

add in interface DoubleIntegerHeap

Parameters:

o - Key

v - Value

add

public void add(double key,
       int val,
       int max)

Description copied from interface: DoubleIntegerHeap

Add a key-value pair to the heap if it improves the top.

Specified by:

add in interface DoubleIntegerHeap

Parameters:

key - Key

val - Value

max - Desired maximum size

replaceTopElement

public void replaceTopElement(double reinsert,
                     int val)

Description copied from interface: DoubleIntegerHeap

Combined operation that removes the top element, and inserts a new element instead.

Specified by:

replaceTopElement in interface DoubleIntegerHeap

Parameters:

reinsert - Key of new element

val - Value of new element

heapifyUp

private void heapifyUp(int twopos,
             double cur,
             int val)

Heapify-Up method for 2-ary heap.

Parameters:

twopos - Position in 2-ary heap.

cur - Current object

val - Current value

poll

public void poll()

Description copied from interface: DoubleIntegerHeap

Remove the first element

Specified by:

poll in interface DoubleIntegerHeap

heapifyDown

private void heapifyDown(double cur,
               int val)

Invoke heapify-down for the root object.

Parameters:

cur - Object to insert.

val - Value to reinsert.

peekKey

public double peekKey()

Description copied from interface: DoubleIntegerHeap

Get the current top key

Specified by:

peekKey in interface DoubleIntegerHeap

Returns:

Top key

peekValue

public int peekValue()

Description copied from interface: DoubleIntegerHeap

Get the current top value

Specified by:

peekValue in interface DoubleIntegerHeap

Returns:

Value

toString

public String toString()

Overrides:

toString in class Object

unsortedIter

public DoubleIntegerMinHeap.UnsortedIter unsortedIter()

Description copied from interface: DoubleIntegerHeap

Get an unsorted iterator to inspect the heap.

Specified by:

unsortedIter in interface DoubleIntegerHeap

Returns:

Iterator