Maxent_Chunk_Annotator: Apache OpenNLP based chunk annotators

In openNLP: Apache OpenNLP Tools Interface

Apache OpenNLP based chunk annotators

Description

Generate an annotator which computes chunk annotations using the Apache OpenNLP Maxent chunker.

Usage

Maxent_Chunk_Annotator(language = "en", probs = FALSE, model = NULL)

Arguments

language	a character string giving the ISO-639 code of the language being processed by the annotator.
probs	a logical indicating whether the computed annotations should provide the token probabilities obtained from the Maxent model as their ‘chunk_prob’ feature.
model	a character string giving the path to the Maxent model file to be used, or NULL indicating to use a default model file for the given language (if available, see Details).

Details

See https://opennlp.sourceforge.net/models-1.5/ for available model files. These can conveniently be made available to R by installing the respective openNLPmodels.language package from the repository at https://datacube.wu.ac.at.

Value

An Annotator object giving the generated chunk annotator.

See Also

https://opennlp.apache.org for more information about Apache OpenNLP.

Examples

## Requires package 'openNLPmodels.en' from the repository at
## <https://datacube.wu.ac.at>.
if(nzchar(system.file(package = "openNLPmodels.en"))) {
    use("NLP")
    ## Some text.
    s <- paste(c("Pierre Vinken, 61 years old, will join the board as a ",
                 "nonexecutive director Nov. 29.\n",
                 "Mr. Vinken is chairman of Elsevier N.V., ",
                 "the Dutch publishing group."),
               collapse = "")
    s <- as.String(s)

    ## Chunking needs word token annotations with POS tags.
    sent_token_annotator <- Maxent_Sent_Token_Annotator()
    word_token_annotator <- Maxent_Word_Token_Annotator()
    pos_tag_annotator <- Maxent_POS_Tag_Annotator()
    a3 <- annotate(s,
                   list(sent_token_annotator,
                        word_token_annotator,
                        pos_tag_annotator))

    annotate(s, Maxent_Chunk_Annotator(), a3)
    annotate(s, Maxent_Chunk_Annotator(probs = TRUE), a3)
}

openNLP documentation built on July 13, 2026, 5:08 p.m.