edu.northwestern.at.morphadorner.corpuslinguistics.textsegmenter.struct

Class ContextVector

java.lang.Object

edu.northwestern.at.morphadorner.corpuslinguistics.textsegmenter.struct.ContextVector

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable

public class ContextVector
extends java.lang.Object
implements java.io.Externalizable

Context vector. Maps string to frequency count.

Author:

Freddy Choi, Philip R. Burns. Modified for integration in MorphAdorner.

Use of this code is free for academic, education, research and other non-profit making uses only.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	ContextVector.Frequency Holds an externalizable frequency (count).

Field Summary

Fields

Modifier and Type	Field and Description
protected int	sum
protected java.util.Map<java.lang.String,ContextVector.Frequency>	table Labeled frquencies.

Constructor Summary

Constructors

Constructor and Description
ContextVector() Create ContextVector.

Method Summary

Methods

Modifier and Type	Method and Description
static double	cos(ContextVector a, ContextVector b) Compute the cosine of vector a and b
static double	cos(ContextVector a, ContextVector b, EntropyVector tf) Compute the cosine of vector a and b, accounting for term frequency.
static int	dot(ContextVector a, ContextVector b) Compute the dot product of vector a and b.
static int	freq(java.lang.String key, ContextVector vector) Get the frequency count of key in context vector
static int	inc(java.lang.String key, int increment, ContextVector vector) Increment frequency count of key.
static java.lang.String[]	keys(ContextVector v) Get the list of context vector keys.
void	readExternal(java.io.ObjectInput in) Read ContextVector from object file.
static int	sum(ContextVector vector) Get the sum of frequencies
void	writeExternal(java.io.ObjectOutput out) Save ContextVector to file as object.

Methods inherited from class java.lang.Object

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

Field Detail

table

protected java.util.Map<java.lang.String,ContextVector.Frequency> table

Labeled frquencies.

sum

protected int sum

Constructor Detail

ContextVector

public ContextVector()

Create ContextVector.

Method Detail

cos

public static double cos(ContextVector a,
         ContextVector b)

Compute the cosine of vector a and b

Parameters:

a - First context vector.

b - Second context vector.

Returns:

Cosine of angle between vectors a and b.

cos

public static double cos(ContextVector a,
         ContextVector b,
         EntropyVector tf)

Compute the cosine of vector a and b, accounting for term frequency.

Parameters:

a - First vector.

b - Second vector.

tf - Term frequency vector.

Returns:

cosine value.

dot

public static int dot(ContextVector a,
      ContextVector b)

Compute the dot product of vector a and b.

Parameters:

a - first vector.

b - second vector.

Returns:

dot product.

freq

public static int freq(java.lang.String key,
       ContextVector vector)

Get the frequency count of key in context vector

Parameters:

key - The key.

vector - The context vector.

Returns:

The frequency count.

inc

public static int inc(java.lang.String key,
      int increment,
      ContextVector vector)

Increment frequency count of key.

Parameters:

key - The key.

increment - The increment value.

vector - The context vector.

Returns:

Updated frequency.

keys

public static java.lang.String[] keys(ContextVector v)

Get the list of context vector keys.

Parameters:

v - The context vector.

Returns:

Keys as a string array.

readExternal

public final void readExternal(java.io.ObjectInput in)
                        throws java.io.IOException,
                               java.lang.ClassNotFoundException

Read ContextVector from object file.

Specified by:

readExternal in interface java.io.Externalizable

Parameters:

in - The object input file.

Throws:

java.io.IOException

java.lang.ClassNotFoundException

sum

public static int sum(ContextVector vector)

Get the sum of frequencies

Parameters:

vector - The context vector.

Returns:

Sum of frequencies in vector.

writeExternal

public final void writeExternal(java.io.ObjectOutput out)
                         throws java.io.IOException

Save ContextVector to file as object.

Specified by:

writeExternal in interface java.io.Externalizable

Parameters:

out - The object output file.

Throws:

java.io.IOException