com.wantedtech.common.xpresso.en.sentence.chunker

Class ChunkString

java.lang.Object

com.wantedtech.common.xpresso.en.sentence.chunker.ChunkString

public class ChunkString
extends java.lang.Object

A string-based encoding of a particular chunking of a text. Internally, the ``ChunkString`` class uses a single string to encode the chunking of the input text. This string contains a sequence of angle-bracket delimited tags, with chunking indicated by braces. An example of this encoding is::

        
        {<DT><JJ><NN>}<VBN><IN>{<DT><NN>}<.>{<DT><NN>}<VBD><.>
    
        

``ChunkString`` are created from tagged texts (i.e., lists of ``tokens`` whose type is ``TaggedType``). Initially, nothing is chunked. The chunking of a ``ChunkString`` can be modified with the ``xform()`` method, which uses a regular expression to transform the string representation. These transformations should only add and remove braces; they should *not* modify the sequence of angle-bracket delimited tags. :type _str: str :ivar _str: The internal string representation of the text's encoding. This string representation contains a sequence of angle-bracket delimited tags, with chunking indicated by braces. An example of this encoding is::

        

            {<DT><JJ><NN>}<VBN><IN>{<DT><NN>}<.>{<DT><NN>}<VBD><.>
    
        

Author:

andriy.burkov

Constructor Summary

Constructors

Constructor and Description
ChunkString(Node chunk_struct) """ Construct a new ``ChunkString`` that encodes the chunking of the text ``tagged_tokens``.

Method Summary

Modifier and Type	Method and Description
Node	to_chunkstruct(java.lang.String label) Return the chunk structure encoded by this ``ChunkString``.
java.lang.String	toString()
void	xform(Regex regexp, java.lang.String repl) """ Apply the given transformation to the string encoding of this ``ChunkString``.

Methods inherited from class java.lang.Object

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

Constructor Detail

ChunkString

public ChunkString(Node chunk_struct)

""" Construct a new ``ChunkString`` that encodes the chunking of the text ``tagged_tokens``.

Parameters:

chunk_struct: - The chunk structure to be further chunked.

Method Detail

to_chunkstruct

public Node to_chunkstruct(java.lang.String label)

Return the chunk structure encoded by this ``ChunkString``.

Parameters:

label - : a String label to use for chunk nodes

Returns:

a tree with tokens and chunks

xform

public void xform(Regex regexp,
                  java.lang.String repl)

""" Apply the given transformation to the string encoding of this ``ChunkString``. In particular, find all occurrences that match ``regexp``, and replace them using ``repl`` (as done by ``re.sub``). This transformation should only add and remove braces; it should *not* modify the sequence of angle-bracket delimited tags. Furthermore, this transformation may not result in improper bracketing. Note, in particular, that bracketing may not be nested.

Parameters:

regexp: - A regular expression matching the substring that should be replaced. This will typically include a named group, which can be used by ``repl``.

repl: - An expression specifying what should replace the matched substring. Typically, this will include a named replacement group, specified by ``regexp``. """

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object