javatools.parsers
Class PlingStemmer

java.lang.Object
  javatools.parsers.PlingStemmer

public class PlingStemmer
extends java.lang.Object

This class is part of the Java Tools (see http://mpii.de/yago-naga/javatools). It is licensed under the Creative Commons Attribution License (see http://creativecommons.org/licenses/by/3.0) by the YAGO-NAGA team (see http://mpii.de/yago-naga). The PlingStemmer stems an English noun (plural or singular) to its singular form. It deals with "firemen"->"fireman", it knows Greek stuff like "appendices"->"appendix" and yes, it was a lot of work to compile these exceptions. Examples:

      System.out.println(PlingStemmer.stem("boy"));
      ----> boy
      System.out.println(PlingStemmer.stem("boys"));
      ----> boy
      System.out.println(PlingStemmer.stem("biophysics"));
      ---->  biophysics
      System.out.println(PlingStemmer.stem("automata"));
      ----> automaton
      System.out.println(PlingStemmer.stem("genus"));
      ----> genus
      System.out.println(PlingStemmer.stem("emus"));
      ----> emu
  

There are a number of word forms that can either be plural or singular. Examples include "physics" (the science or the plural of "physic" (the medicine)), "quarters" (the housing or the plural of "quarter" (1/4)) or "people" (the singular of "peoples" or the plural of "person"). In these cases, the stemmer assumes the word is a plural form and returns the singular form. The methods isPlural, isSingular and isPluralAndSingular can be used to differentiate the cases.

It cannot be guaranteed that the stemmer correctly stems a plural word or correctly ignores a singular word -- let alone that it treats an ambiguous word form in the way expected by the user.

The PlingStemmer uses material from WordNet.

It requires the class FinalSet from the Java Tools.

Field Summary

static java.util.Set<java.lang.String>	category00 Words that do not have a distinct plural form (like "atlas" etc.)
static java.util.Set<java.lang.String>	categoryCHE_CHES Words that change from "-che" to "-ches" (like "brioche" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryEX_ICES Words that change from "-ex" to "-ices" (like "index" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryICS Words that end with "-ics" and do not exist as nouns without the 's' (like "aerobics" etc.)
static java.util.Set<java.lang.String>	categoryIE_IES Words that change from "-ie" to "-ies" (like "auntie" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryIS_ES Words that change from "-is" to "-es" (like "axis" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryIX_ICES Words that change from "-ix" to "-ices" (like "appendix" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryO_I Words that change from "-o" to "-i" (like "libretto" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryOE_OES Words that change from "-oe" to "-oes" (like "toe" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryON_A Words that change from "-on" to "-a" (like "phenomenon" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categorySE_SES Words that end in "-se" in their plural forms (like "nurse" etc.)
static java.util.Set<java.lang.String>	categorySSE_SSES Words that change from "-sse" to "-sses" (like "finesse" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryU_US Words that change from "-u" to "-us" (like "emu" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryUM_A Words that change from "-um" to "-a" (like "curriculum" etc.), listed in their plural forms
static java.util.Set<java.lang.String>	categoryUS_I Words that change from "-us" to "-i" (like "fungus" etc.), listed in their plural forms
static java.util.Map<java.lang.String,java.lang.String>	irregular Maps irregular Germanic English plural nouns to their singular form
static java.util.Set<java.lang.String>	singAndPlur Contains word forms that can either be plural or singular

Constructor Summary

PlingStemmer()

Method Summary

static java.lang.String	cut(java.lang.String s, java.lang.String suffix) Cuts a suffix from a string (that is the number of chars given by the suffix)
static boolean	isPlural(java.lang.String s) Tells whether a word form is plural.
static boolean	isSingular(java.lang.String s) Tells whether a word form is singular.
static boolean	isSingularAndPlural(java.lang.String s) Tells whether a word form is the singular form of one word and at the same time the plural form of another.
static void	main(java.lang.String[] argv) Test routine
static boolean	noLatin(java.lang.String s) Returns true if a word is probably not Latin
static java.lang.String	stem(java.lang.String s) Stems an English noun

Methods inherited from class java.lang.Object

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

Field Detail

categorySE_SES

public static java.util.Set<java.lang.String> categorySE_SES

Words that end in "-se" in their plural forms (like "nurse" etc.)

category00

public static java.util.Set<java.lang.String> category00

Words that do not have a distinct plural form (like "atlas" etc.)

categoryUM_A

public static java.util.Set<java.lang.String> categoryUM_A

Words that change from "-um" to "-a" (like "curriculum" etc.), listed in their plural forms

categoryON_A

public static java.util.Set<java.lang.String> categoryON_A

Words that change from "-on" to "-a" (like "phenomenon" etc.), listed in their plural forms

categoryO_I

public static java.util.Set<java.lang.String> categoryO_I

Words that change from "-o" to "-i" (like "libretto" etc.), listed in their plural forms

categoryUS_I

public static java.util.Set<java.lang.String> categoryUS_I

Words that change from "-us" to "-i" (like "fungus" etc.), listed in their plural forms

categoryIX_ICES

public static java.util.Set<java.lang.String> categoryIX_ICES

Words that change from "-ix" to "-ices" (like "appendix" etc.), listed in their plural forms

categoryIS_ES

public static java.util.Set<java.lang.String> categoryIS_ES

Words that change from "-is" to "-es" (like "axis" etc.), listed in their plural forms

categoryOE_OES

public static java.util.Set<java.lang.String> categoryOE_OES

Words that change from "-oe" to "-oes" (like "toe" etc.), listed in their plural forms

categoryEX_ICES

public static java.util.Set<java.lang.String> categoryEX_ICES

Words that change from "-ex" to "-ices" (like "index" etc.), listed in their plural forms

categoryU_US

public static java.util.Set<java.lang.String> categoryU_US

Words that change from "-u" to "-us" (like "emu" etc.), listed in their plural forms

categorySSE_SSES

public static java.util.Set<java.lang.String> categorySSE_SSES

Words that change from "-sse" to "-sses" (like "finesse" etc.), listed in their plural forms

categoryCHE_CHES

public static java.util.Set<java.lang.String> categoryCHE_CHES

Words that change from "-che" to "-ches" (like "brioche" etc.), listed in their plural forms

categoryICS

public static java.util.Set<java.lang.String> categoryICS

Words that end with "-ics" and do not exist as nouns without the 's' (like "aerobics" etc.)

categoryIE_IES

public static java.util.Set<java.lang.String> categoryIE_IES

Words that change from "-ie" to "-ies" (like "auntie" etc.), listed in their plural forms

irregular

public static java.util.Map<java.lang.String,java.lang.String> irregular

Maps irregular Germanic English plural nouns to their singular form

singAndPlur

public static java.util.Set<java.lang.String> singAndPlur

Contains word forms that can either be plural or singular

Constructor Detail

PlingStemmer

public PlingStemmer()

Method Detail

isPlural

public static boolean isPlural(java.lang.String s)

Tells whether a word form is plural. This method just checks whether the stem method alters the word

isSingular

public static boolean isSingular(java.lang.String s)

Tells whether a word form is singular. Note that a word can be both plural and singular

isSingularAndPlural

public static boolean isSingularAndPlural(java.lang.String s)

Tells whether a word form is the singular form of one word and at the same time the plural form of another.

cut

public static java.lang.String cut(java.lang.String s,
                                   java.lang.String suffix)

Cuts a suffix from a string (that is the number of chars given by the suffix)

noLatin

public static boolean noLatin(java.lang.String s)

Returns true if a word is probably not Latin

stem

public static java.lang.String stem(java.lang.String s)

Stems an English noun

main

public static void main(java.lang.String[] argv)
                 throws java.lang.Exception

Test routine

Throws:

java.lang.Exception