ai.djl.modality.nlp.preprocess

Class HyphenNormalizer

java.lang.Object

ai.djl.modality.nlp.preprocess.HyphenNormalizer

All Implemented Interfaces:

TextProcessor

public class HyphenNormalizer
extends java.lang.Object
implements TextProcessor

Unicode normalization does not take care of "exotic" hyphens that we normally do not want in NLP input. This preprocessor turns all Hyphens into "normal" ASCII minus-hyphen characters (U+002D). Invisible soft hyphens are dropped from the input.

Constructor Summary

Constructors

Constructor and Description
HyphenNormalizer()

Method Summary

Modifier and Type	Method and Description
static boolean	isHyphenLike(java.lang.Integer codePoint) Returns whether the given code point is a hyphen-like codepoint.
static java.lang.String	normalizeHyphens(java.lang.String s) Replaces hyphen like codepoints by ASCII "-", removes soft hyphens.
java.util.List<java.lang.String>	preprocess(java.util.List<java.lang.String> tokens) Applies the preprocessing defined to the given input tokens.

Methods inherited from class java.lang.Object

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

Constructor Detail

HyphenNormalizer

public HyphenNormalizer()

Method Detail

isHyphenLike

public static boolean isHyphenLike(java.lang.Integer codePoint)

Returns whether the given code point is a hyphen-like codepoint. Tests for hyphen-minus, tilde, soft hyphen, armenian hyphen, hebrew punctuation maqaf, canadian syllabics hyphen, mongolian hyphen, non-breaking hyphen, figure dash, en dash, em dash, horizontal bar, swung dash, superscript minus, subscript minus, minus sign, double oblique hyphen, two-em dash, three-em dash, wave dash, wavy dash, katakana-hiragana double hyphen

Parameters:

codePoint - A unicode code point. (not a char!)

Returns:

true: given code point represents a hyphen-like glyph

normalizeHyphens

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

Replaces hyphen like codepoints by ASCII "-", removes soft hyphens.

Parameters:

s - input string to replace hyphens in

Returns:

the same string with soft hyphens dropped and hyphen-like codepoints replaced by an ASCII minus.

preprocess

public java.util.List<java.lang.String> preprocess(java.util.List<java.lang.String> tokens)

Description copied from interface: TextProcessor

Applies the preprocessing defined to the given input tokens.

Specified by:

preprocess in interface TextProcessor

Parameters:

tokens - the tokens created after the input text is tokenized

Returns:

the preprocessed tokens