Stanford CoreNLP wrapper for Apache Spark

This package wraps Stanford CoreNLP annotators as Spark DataFrame functions following the simple APIs introduced in Stanford CoreNLP 3.6.0.

This package requires Java 8 and CoreNLP 3.6.0 to run. Users must include CoreNLP model jars as dependencies to use language models.

All functions are defined under com.databricks.spark.corenlp.functions.

• cleanxml: Cleans XML tags in a document and returns the cleaned document.
• tokenize: Tokenizes a sentence into words.
• ssplit: Splits a document into sentences.
• pos: Generates the part of speech tags of the sentence.
• lemma: Generates the word lemmas of the sentence.
• ner: Generates the named entity tags of the sentence.
• depparse: Generates the semantic dependencies of the sentence and returns a flattened list of (source, sourceIndex, relation, target, targetIndex, weight) relation tuples.
• coref: Generates the coref chains in the document and returns a list of (rep, mentions) chain tuples, where mentions are in the format of (sentNum, startIndex, mention).
• natlog: Generates the Natural Logic notion of polarity for each token in a sentence, returned as up, down, or flat.
• openie: Generates a list of Open IE triples as flat (subject, relation, target, confidence) tuples.
• sentiment: Measures the sentiment of an input sentence on a scale of 0 (strong negative) to 4 (strong positive).

Users can chain the functions to create pipeline, for example:

import org.apache.spark.sql.functions._
import com.databricks.spark.corenlp.functions._

import sqlContext.implicits._

val input = Seq(
  (1, "<xml>Stanford University is located in California. It is a great university.</xml>")
).toDF("id", "text")

val output = input
  .select(cleanxml('text).as('doc))
  .select(explode(ssplit('doc)).as('sen))
  .select('sen, tokenize('sen).as('words), ner('sen).as('nerTags), sentiment('sen).as('sentiment))

output.show(truncate = false)

+----------------------------------------------+------------------------------------------------------+--------------------------------------------------+---------+
|sen                                           |words                                                 |nerTags                                           |sentiment|
+----------------------------------------------+------------------------------------------------------+--------------------------------------------------+---------+
|Stanford University is located in California .|[Stanford, University, is, located, in, California, .]|[ORGANIZATION, ORGANIZATION, O, O, O, LOCATION, O]|1        |
|It is a great university .                    |[It, is, a, great, university, .]                     |[O, O, O, O, O, O]                                |4        |
+----------------------------------------------+------------------------------------------------------+--------------------------------------------------+---------+

Acknowledgements

Many thanks to Jason Bolton from the Stanford NLP Group for API discussions.