python/ml/n_gram_example.py

0001 #
0002 # Licensed to the Apache Software Foundation (ASF) under one or more
0003 # contributor license agreements.  See the NOTICE file distributed with
0004 # this work for additional information regarding copyright ownership.
0005 # The ASF licenses this file to You under the Apache License, Version 2.0
0006 # (the "License"); you may not use this file except in compliance with
0007 # the License.  You may obtain a copy of the License at
0008 #
0009 #    http://www.apache.org/licenses/LICENSE-2.0
0010 #
0011 # Unless required by applicable law or agreed to in writing, software
0012 # distributed under the License is distributed on an "AS IS" BASIS,
0013 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014 # See the License for the specific language governing permissions and
0015 # limitations under the License.
0016 #
0017
0018 from __future__ import print_function
0019
0020 # $example on$
0021 from pyspark.ml.feature import NGram
0022 # $example off$
0023 from pyspark.sql import SparkSession
0024
0025 if __name__ == "__main__":
0026     spark = SparkSession\
0027         .builder\
0028         .appName("NGramExample")\
0029         .getOrCreate()
0030
0031     # $example on$
0032     wordDataFrame = spark.createDataFrame([
0033         (0, ["Hi", "I", "heard", "about", "Spark"]),
0034         (1, ["I", "wish", "Java", "could", "use", "case", "classes"]),
0035         (2, ["Logistic", "regression", "models", "are", "neat"])
0036     ], ["id", "words"])
0037
0038     ngram = NGram(n=2, inputCol="words", outputCol="ngrams")
0039
0040     ngramDataFrame = ngram.transform(wordDataFrame)
0041     ngramDataFrame.select("ngrams").show(truncate=False)
0042     # $example off$
0043
0044     spark.stop()