python/ml/chisq_selector_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 from pyspark.sql import SparkSession
0021 # $example on$
0022 from pyspark.ml.feature import ChiSqSelector
0023 from pyspark.ml.linalg import Vectors
0024 # $example off$
0025
0026 if __name__ == "__main__":
0027     spark = SparkSession\
0028         .builder\
0029         .appName("ChiSqSelectorExample")\
0030         .getOrCreate()
0031
0032     # $example on$
0033     df = spark.createDataFrame([
0034         (7, Vectors.dense([0.0, 0.0, 18.0, 1.0]), 1.0,),
0035         (8, Vectors.dense([0.0, 1.0, 12.0, 0.0]), 0.0,),
0036         (9, Vectors.dense([1.0, 0.0, 15.0, 0.1]), 0.0,)], ["id", "features", "clicked"])
0037
0038     selector = ChiSqSelector(numTopFeatures=1, featuresCol="features",
0039                              outputCol="selectedFeatures", labelCol="clicked")
0040
0041     result = selector.fit(df).transform(df)
0042
0043     print("ChiSqSelector output with top %d features selected" % selector.getNumTopFeatures())
0044     result.show()
0045     # $example off$
0046
0047     spark.stop()