Overview | Package | Class | Tree | Deprecated | Index | Help | Weka's home

PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD

## weka.core.stemmers
Class SnowballStemmer

    java.lang.Object
      weka.core.stemmers.SnowballStemmer

All Implemented Interfaces:
  java.io.Serializable, OptionHandler, RevisionHandler, Stemmer

    public class SnowballStemmer

extends java.lang.Object
implements Stemmer, OptionHandler

A wrapper class for the Snowball stemmers. Only available if the Snowball classes are in the classpath.
If the class discovery is not dynamic, i.e., the property 'UseDynamic' in the props file 'weka/gui/GenericPropertiesCreator.props' is 'false', then the property 'org.tartarus.snowball.SnowballProgram' in the 'weka/gui/GenericObjectEditor.props' file has to be uncommented as well. If necessary you have to discover and fill in the snowball stemmers manually. You can use the 'weka.core.ClassDiscovery' for this:
java weka.core.ClassDiscovery org.tartarus.snowball.SnowballProgram org.tartarus.snowball.ext
For more information visit these web sites:
http://weka.wikispaces.com/Stemmers
http://snowball.tartarus.org/

Valid options are:

     -S <name>
      The name of the snowball stemmer (default 'porter').
      available stemmers:
         danish, dutch, english, finnish, french, german, italian,
         norwegian, porter, portuguese, russian, spanish, swedish

Version:
  $Revision: 5836 $
Author:
  FracPete (fracpete at waikato dot ac dot nz)
See Also:
  Serialized Form

Field Summary
`static java.lang.String` | `PACKAGE` the package name for snowball.
`static java.lang.String` | `PACKAGE_EXT` the package name where the stemmers are located.

Constructor Summary
`SnowballStemmer()` initializes the stemmer ("porter").
`SnowballStemmer(java.lang.String name)` initializes the stemmer with the given stemmer.

Method Summary
`java.lang.String[]` | `getOptions()` Gets the current settings of the classifier.
`java.lang.String` | `getRevision()` Returns the revision string.
`java.lang.String` | `getStemmer()` returns the name of the current stemmer, null if none is set.
`java.lang.String` | `globalInfo()` Returns a string describing the stemmer.
`static boolean` | `isPresent()` returns whether Snowball is present or not, i.e.
`java.util.Enumeration` | `listOptions()` Returns an enumeration describing the available options.
`static java.util.Enumeration` | `listStemmers()` returns an enumeration over all currently stored stemmer names.
`static void` | `main(java.lang.String[] args)` Runs the stemmer with the given options.
`void` | `setOptions(java.lang.String[] options)` Parses the options.
`void` | `setStemmer(java.lang.String name)` sets the stemmer with the given name, e.g., "porter".
`java.lang.String` | `stem(java.lang.String word)` Returns the word in its stemmed form.
`java.lang.String` | `stemmerTipText()` Returns the tip text for this property.
`java.lang.String` | `toString()` returns a string representation of the stemmer.

Methods inherited from class java.lang.Object
`equals, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Field Detail

### PACKAGE

    public static final java.lang.String PACKAGE

  the package name for snowball.

  See Also:
    Constant Field Values

### PACKAGE_EXT

    public static final java.lang.String PACKAGE_EXT

  the package name where the stemmers are located.

  See Also:
    Constant Field Values

Constructor Detail

### SnowballStemmer

    public SnowballStemmer()

  initializes the stemmer ("porter").

### SnowballStemmer

    public SnowballStemmer(java.lang.String name)

  initializes the stemmer with the given stemmer.

  Parameters:
    `name` - the name of the stemmer

Method Detail

### globalInfo

    public java.lang.String globalInfo()

  Returns a string describing the stemmer.

  Returns:
    a description suitable for displaying in the explorer/experimenter gui

### listOptions

    public java.util.Enumeration listOptions()

  Returns an enumeration describing the available options.

  Specified by:
    `listOptions` in interface `OptionHandler`
  Returns:
    an enumeration of all the available options.

### setOptions

    public void setOptions(java.lang.String[] options)
                    throws java.lang.Exception

  Parses the options.

  Valid options are:

       -S <name>
        The name of the snowball stemmer (default 'porter').
        available stemmers:
           danish, dutch, english, finnish, french, german, italian,
           norwegian, porter, portuguese, russian, spanish, swedish

  Specified by:
    `setOptions` in interface `OptionHandler`
  Parameters:
    `options` - the options to parse
  Throws:
    `java.lang.Exception` - if parsing fails

### getOptions

    public java.lang.String[] getOptions()

  Gets the current settings of the classifier.

  Specified by:
    `getOptions` in interface `OptionHandler`
  Returns:
    an array of strings suitable for passing to setOptions

### isPresent

    public static boolean isPresent()

  returns whether Snowball is present or not, i.e. whether the classes are in the classpath or not

  Returns:
    whether Snowball is available

### listStemmers

    public static java.util.Enumeration listStemmers()

  returns an enumeration over all currently stored stemmer names.

  Returns:
    all available stemmers

### getStemmer

    public java.lang.String getStemmer()

  returns the name of the current stemmer, null if none is set.

  Returns:
    the name of the stemmer

### setStemmer

    public void setStemmer(java.lang.String name)

  sets the stemmer with the given name, e.g., "porter".

  Parameters:
    `name` - the name of the stemmer, e.g., "porter"

### stemmerTipText

    public java.lang.String stemmerTipText()

  Returns the tip text for this property.

  Returns:
    tip text for this property suitable for displaying in the explorer/experimenter gui

### stem

    public java.lang.String stem(java.lang.String word)

  Returns the word in its stemmed form.

  Specified by:
    `stem` in interface `Stemmer`
  Parameters:
    `word` - the unstemmed word
  Returns:
    the stemmed word

### toString

    public java.lang.String toString()

  returns a string representation of the stemmer.

  Overrides:
    `toString` in class `java.lang.Object`
  Returns:
    a string representation of the stemmer

### getRevision

    public java.lang.String getRevision()

  Returns the revision string.

  Specified by:
    `getRevision` in interface `RevisionHandler`
  Returns:
    the revision

### main

    public static void main(java.lang.String[] args)

  Runs the stemmer with the given options.

  Parameters:
    `args` - the options

Overview | Package | Class | Tree | Deprecated | Index | Help | Weka's home

PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD