org.apache.spark.examples.ml.CountVectorizerExample.scala Maven / Gradle / Ivy

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// scalastyle:off println
package org.apache.spark.examples.ml

// $example on$
import org.apache.spark.ml.feature.{CountVectorizer, CountVectorizerModel}
// $example off$
import org.apache.spark.sql.SparkSession

object CountVectorizerExample {
  def main(args: Array[String]): Unit = {
    val spark = SparkSession
      .builder
      .appName("CountVectorizerExample")
      .getOrCreate()

    // $example on$
    val df = spark.createDataFrame(Seq(
      (0, Array("a", "b", "c")),
      (1, Array("a", "b", "b", "c", "a"))
    )).toDF("id", "words")

    // fit a CountVectorizerModel from the corpus
    val cvModel: CountVectorizerModel = new CountVectorizer()
      .setInputCol("words")
      .setOutputCol("features")
      .setVocabSize(3)
      .setMinDF(2)
      .fit(df)

    // alternatively, define CountVectorizerModel with a-priori vocabulary
    val cvm = new CountVectorizerModel(Array("a", "b", "c"))
      .setInputCol("words")
      .setOutputCol("features")

    cvModel.transform(df).show(false)
    // $example off$

    spark.stop()
  }
}
// scalastyle:on println