rita
Class RiStemmer

java.lang.Object
  rita.RiObject
      rita.RiStemmer

All Implemented Interfaces:

processing.core.PConstants, RiStemmerIF, RiConstants

public class RiStemmer
extends RiObject
implements RiStemmerIF

A simple set of stemmers for extracting base roots from a word by removing prefixes and suffixes. For example, the words 'run', 'runs', and 'running' all have "run" as their stem.

    String[] tests = { "run", "runs", "running" };
    RiStemmer stem = new RiStemmer(this);
    for (int i = 0; i < tests.length; i++)
      System.out.println(stem.stem(tests[i]));
 

This class provides a # of implementations, each specified by a type constant.
For example, to use the Lancaster (or Paice-Husk) algorithm instead of the Porter (the default), create the stemmer as follows:

 RiStemmer stem = new RiStemmer(this, LANCASTER_STEMMER);
 

For a comparison of the various algorithms, see
http://www.comp.lancs.ac.uk/computing/research/stemming/Links/algorithms.htm

Field Summary

static int	LANCASTER_STEMMER Type constant for Lancaster stemmer
static int	LOVINS_STEMMER Type constant for Pacie-Husk stemmer
static int	PLING_STEMMER Type constant for Pling stemmer
static int	PORTER_STEMMER Type constant for Porter stemmer

Fields inherited from interface rita.support.RiConstants

BEHAVIOR_COMPLETED, BOUNDING_BOX_ALPHA, BRILL_POS_TAGGER, EASE_IN, EASE_IN_CUBIC, EASE_IN_EXPO, EASE_IN_OUT, EASE_IN_OUT_CUBIC, EASE_IN_OUT_EXPO, EASE_IN_OUT_QUARTIC, EASE_IN_OUT_SINE, EASE_IN_QUARTIC, EASE_IN_SINE, EASE_OUT, EASE_OUT_CUBIC, EASE_OUT_EXPO, EASE_OUT_QUARTIC, EASE_OUT_SINE, ESS, FADE_COLOR, FADE_IN, FADE_OUT, FADE_TO_TEXT, FIRST_PERSON, FUTURE_TENSE, ID, LERP, LINEAR, MAXENT_POS_TAGGER, MINIM, MOVE, MUTABLE, PAST_TENSE, PHONEME_BOUNDARY, PHONEMES, PLURAL, POS, PRESENT_TENSE, SCALE_TO, SECOND_PERSON, SENTENCE_BOUNDARY, SINGULAR, SONIA, SPEECH_COMPLETED, STRESSES, SYLLABLE_BOUNDARY, SYLLABLES, TEXT, TEXT_ENTERED, THIRD_PERSON, TIMER, TIMER_COMPLETED, TIMER_TICK, TOKENS, UNKNOWN, WORD_BOUNDARY

Fields inherited from interface processing.core.PConstants

A, AB, ADD, AG, ALPHA, ALPHA_MASK, ALT, AMBIENT, AR, ARC, ARGB, ARROW, B, BACKSPACE, BASELINE, BEEN_LIT, BEVEL, BLEND, BLUE_MASK, BLUR, BOTTOM, BOX, BURN, CENTER, CENTER_DIAMETER, CENTER_RADIUS, CHATTER, CLOSE, CMYK, CODED, COMPLAINT, CONTROL, CORNER, CORNERS, CROSS, CUSTOM, DA, DARKEST, DB, DEG_TO_RAD, DELETE, DG, DIAMETER, DIFFERENCE, DILATE, DIRECTIONAL, DISABLE_ACCURATE_TEXTURES, DISABLE_DEPTH_SORT, DISABLE_DEPTH_TEST, DISABLE_OPENGL_2X_SMOOTH, DISABLE_OPENGL_ERROR_REPORT, DODGE, DOWN, DR, DXF, EB, EDGE, EG, ELLIPSE, ENABLE_ACCURATE_TEXTURES, ENABLE_DEPTH_SORT, ENABLE_DEPTH_TEST, ENABLE_NATIVE_FONTS, ENABLE_OPENGL_2X_SMOOTH, ENABLE_OPENGL_4X_SMOOTH, ENABLE_OPENGL_ERROR_REPORT, ENTER, EPSILON, ER, ERODE, ERROR_BACKGROUND_IMAGE_FORMAT, ERROR_BACKGROUND_IMAGE_SIZE, ERROR_PUSHMATRIX_OVERFLOW, ERROR_PUSHMATRIX_UNDERFLOW, ERROR_TEXTFONT_NULL_PFONT, ESC, EXCLUSION, G, GIF, GRAY, GREEN_MASK, HALF_PI, HAND, HARD_LIGHT, HINT_COUNT, HSB, IMAGE, INVERT, JAVA2D, JPEG, LEFT, LIGHTEST, LINE, LINES, LINUX, MACOSX, MAX_FLOAT, MAX_INT, MIN_FLOAT, MIN_INT, MITER, MODEL, MULTIPLY, NORMAL, NORMALIZED, NX, NY, NZ, OPAQUE, OPEN, OPENGL, ORTHOGRAPHIC, OTHER, OVERLAY, P2D, P3D, PATH, PDF, PERSPECTIVE, PI, platformNames, POINT, POINTS, POLYGON, POSTERIZE, PROBLEM, PROJECT, QUAD, QUAD_STRIP, QUADS, QUARTER_PI, R, RAD_TO_DEG, RADIUS, RECT, RED_MASK, REPLACE, RETURN, RGB, RIGHT, ROUND, SA, SB, SCREEN, SG, SHAPE, SHIFT, SHINE, SOFT_LIGHT, SPB, SPG, SPHERE, SPOT, SPR, SQUARE, SR, SUBTRACT, SW, TAB, TARGA, THIRD_PI, THRESHOLD, TIFF, TOP, TRIANGLE, TRIANGLE_FAN, TRIANGLE_STRIP, TRIANGLES, TWO_PI, TX, TY, TZ, U, UP, V, VERTEX_FIELD_COUNT, VW, VX, VY, VZ, WAIT, WHITESPACE, WINDOWS, X, Y, Z

Constructor Summary

RiStemmer()

RiStemmer(processing.core.PApplet p)
Creates a default stemmer

RiStemmer(processing.core.PApplet p, int stemmerType)

Method Summary

RiStemmerIF	getStemmer() Returns the concrete stemmer (delegate) object that actually does the work
static void	main(java.lang.String[] args)
java.lang.String	stem(java.lang.String word) Extracts base roots from a word by lower-casing it, then removing prefixes and suffixes.

Methods inherited from class rita.RiObject

dispose, getId, getPApplet, nextId

Methods inherited from class java.lang.Object

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

Field Detail

PLING_STEMMER

public static final int PLING_STEMMER

Type constant for Pling stemmer

See Also:

Constant Field Values

Invisible:

PORTER_STEMMER

public static final int PORTER_STEMMER

Type constant for Porter stemmer

See Also:

Constant Field Values

Invisible:

LANCASTER_STEMMER

public static final int LANCASTER_STEMMER

Type constant for Lancaster stemmer

See Also:

Constant Field Values

Invisible:

LOVINS_STEMMER

public static final int LOVINS_STEMMER

Type constant for Pacie-Husk stemmer

See Also:

Constant Field Values

Invisible:

Constructor Detail

RiStemmer

public RiStemmer()

Invisible:

RiStemmer

public RiStemmer(processing.core.PApplet p)

Creates a default stemmer

RiStemmer

public RiStemmer(processing.core.PApplet p,
                 int stemmerType)

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Method Detail

getStemmer

public RiStemmerIF getStemmer()

Returns the concrete stemmer (delegate) object that actually does the work

Invisible:

stem

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

Extracts base roots from a word by lower-casing it, then removing prefixes and suffixes. For example, the words 'run', 'runs', 'ran', and 'running' all have "run" as their stem.

Specified by:

stem in interface RiStemmerIF

main

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