tl.lin.data.map
Class HMapID

java.lang.Object
  tl.lin.data.map.HMapID

All Implemented Interfaces:

Serializable, Cloneable, MapID

Direct Known Subclasses:

HMapIDW

public class HMapID
extends Object
implements MapID, Cloneable, Serializable

Hash-based implementation of MapID.

See Also:

Serialized Form

Field Summary

Fields inherited from interface tl.lin.data.map.MapID

DEFAULT_VALUE

Constructor Summary

HMapID()
Constructs an empty HMapID with the default initial capacity (1024) and the default load factor (0.75).

HMapID(int initialCapacity)
Constructs an empty HMapID with the specified initial capacity and the default load factor (0.75).

HMapID(int initialCapacity, float loadFactor)
Constructs an empty HMapID with the specified initial capacity and load factor.

HMapID(MapID m)
Constructs a new HMapID with the same mappings as the specified MapID.

Method Summary

void	clear() Removes all of the mappings from this map.
Object	clone() Returns a shallow copy of this HMapID instance: the keys and values themselves are not cloned.
boolean	containsKey(int key) Returns true if this map contains a mapping for the specified key.
boolean	containsValue(double value) Returns true if this map contains one or more mappings with the specified value.
double	dot(MapID m) Computes the dot product of this map with another map.
Set<MapID.Entry>	entrySet() Returns a Set view of the mappings contained in this map.
double	get(int key) Returns the value to which the specified key is mapped, or throws NoSuchElementException if this map contains no mapping for the key.
MapID.Entry[]	getEntriesSortedByValue() Returns entries sorted by descending value.
MapID.Entry[]	getEntriesSortedByValue(int n) Returns top n entries sorted by descending value.
void	increment(int key, double value) Increments the key by some value.
boolean	isEmpty() Returns true if this map contains no key-value mappings.
Set<Integer>	keySet() Returns a Set view of the keys contained in this map.
double	length() Returns the length of the vector represented by this map.
void	normalize() Normalizes values such that the vector represented by this map has unit length.
void	plus(MapID m) Adds values of keys from another map to this map.
double	put(int key, double value) Associates the specified value with the specified key in this map.
void	putAll(MapID m) Copies all of the mappings from the specified map to this map.
double	remove(int key) Removes the mapping for a key from this map if it is present.
int	size() Returns the number of key-value mappings in this map.
String	toString()
Collection<Double>	values() Returns a Collection view of the values contained in this map.

Methods inherited from class java.lang.Object

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

Methods inherited from interface tl.lin.data.map.MapID

equals, hashCode

Constructor Detail

HMapID

public HMapID(int initialCapacity,
              float loadFactor)

Constructs an empty HMapID with the specified initial capacity and load factor.

Parameters:

initialCapacity - the initial capacity

loadFactor - the load factor

Throws:

IllegalArgumentException - if the initial capacity is negative or the load factor is nonpositive

HMapID

public HMapID(int initialCapacity)

Constructs an empty HMapID with the specified initial capacity and the default load factor (0.75).

Parameters:

initialCapacity - the initial capacity.

Throws:

IllegalArgumentException - if the initial capacity is negative.

HMapID

public HMapID()

Constructs an empty HMapID with the default initial capacity (1024) and the default load factor (0.75).

HMapID

public HMapID(MapID m)

Constructs a new HMapID with the same mappings as the specified MapID. The HMapID is created with default load factor (0.75) and an initial capacity sufficient to hold the mappings in the specified MapID.

Parameters:

m - the map whose mappings are to be placed in this map

Throws:

NullPointerException - if the specified map is null

Method Detail

size

public int size()

Description copied from interface: MapID

Returns the number of key-value mappings in this map.

Specified by:

size in interface MapID

Returns:

the number of key-value mappings in this map

isEmpty

public boolean isEmpty()

Description copied from interface: MapID

Returns true if this map contains no key-value mappings.

Specified by:

isEmpty in interface MapID

Returns:

true if this map contains no key-value mappings

get

public double get(int key)

Description copied from interface: MapID

Returns the value to which the specified key is mapped, or throws NoSuchElementException if this map contains no mapping for the key.

Specified by:

get in interface MapID

Parameters:

key - the key whose associated value is to be returned

Returns:

the value to which the specified key is mapped

containsKey

public boolean containsKey(int key)

Description copied from interface: MapID

Returns true if this map contains a mapping for the specified key.

Specified by:

containsKey in interface MapID

Parameters:

key - key whose presence in this map is to be tested

Returns:

true if this map contains a mapping for the specified key

put

public double put(int key,
                  double value)

Description copied from interface: MapID

Associates the specified value with the specified key in this map. If the map previously contained a mapping for the key, the old value is replaced by the specified value.

Specified by:

put in interface MapID

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

putAll

public void putAll(MapID m)

Description copied from interface: MapID

Copies all of the mappings from the specified map to this map.

Specified by:

putAll in interface MapID

Parameters:

m - mappings to be stored in this map

increment

public void increment(int key,
                      double value)

Increments the key by some value. If the key does not exist in the map, its value is set to the parameter value.

Parameters:

key - key to increment

value - increment value

remove

public double remove(int key)

Description copied from interface: MapID

Removes the mapping for a key from this map if it is present. No action is performed if this map does not contain the key.

Specified by:

remove in interface MapID

Parameters:

key - key whose mapping is to be removed from the map

clear

public void clear()

Description copied from interface: MapID

Removes all of the mappings from this map. The map will be empty after this call returns.

Specified by:

clear in interface MapID

containsValue

public boolean containsValue(double value)

Description copied from interface: MapID

Returns true if this map contains one or more mappings with the specified value.

Specified by:

containsValue in interface MapID

Parameters:

value - value whose presence in this map is to be tested

Returns:

true this map contains one or more mappings with the specified value

clone

public Object clone()

Returns a shallow copy of this HMapID instance: the keys and values themselves are not cloned.

Overrides:

clone in class Object

Returns:

a shallow copy of this map

keySet

public Set<Integer> keySet()

Description copied from interface: MapID

Returns a Set view of the keys contained in this map. Note that this is a inefficient operation since it triggers autoboxing of the int keys, which is exactly what this implementation is trying to avoid. Unlike a standard Java Map, values in the backing map cannot be altered with this collection view.

Specified by:

keySet in interface MapID

Returns:

a set view of the keys contained in this map

values

public Collection<Double> values()

Description copied from interface: MapID

Returns a Collection view of the values contained in this map. Note that this is a inefficient operation since it triggers autoboxing of the double values, which is exactly what this implementation is trying to avoid. Unlike a standard Java Map, values in the backing map cannot be altered with this collection view.

Specified by:

values in interface MapID

Returns:

a collection view of the values contained in this map

entrySet

public Set<MapID.Entry> entrySet()

Description copied from interface: MapID

Returns a Set view of the mappings contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa.

Specified by:

entrySet in interface MapID

Returns:

a set view of the mappings contained in this map

toString

public String toString()

Overrides:

toString in class Object

plus

public void plus(MapID m)

Adds values of keys from another map to this map.

Parameters:

m - the other map

dot

public double dot(MapID m)

Computes the dot product of this map with another map.

Parameters:

m - the other map

length

public double length()

Returns the length of the vector represented by this map.

Returns:

length of the vector represented by this map

normalize

public void normalize()

Normalizes values such that the vector represented by this map has unit length.

getEntriesSortedByValue

public MapID.Entry[] getEntriesSortedByValue()

Returns entries sorted by descending value. Ties broken by the key.

Returns:

entries sorted by descending value

getEntriesSortedByValue

public MapID.Entry[] getEntriesSortedByValue(int n)

Returns top n entries sorted by descending value. Ties broken by the key.

Parameters:

n - number of entries to return

Returns:

top n entries sorted by descending value