From 5452457410ffe881773f2f2cdcdc752467b19720 Mon Sep 17 00:00:00 2001 From: Shuo Xiang Date: Mon, 29 Jun 2015 23:50:34 -0700 Subject: [SPARK-8551] [ML] Elastic net python code example Author: Shuo Xiang Closes #6946 from coderxiang/en-java-code-example and squashes the following commits: 7a4bdf8 [Shuo Xiang] address comments cddb02b [Shuo Xiang] add elastic net python example code f4fa534 [Shuo Xiang] Merge remote-tracking branch 'upstream/master' 6ad4865 [Shuo Xiang] Merge remote-tracking branch 'upstream/master' 180b496 [Shuo Xiang] Merge remote-tracking branch 'upstream/master' aa0717d [Shuo Xiang] Merge remote-tracking branch 'upstream/master' 5f109b4 [Shuo Xiang] Merge remote-tracking branch 'upstream/master' c5c5bfe [Shuo Xiang] Merge remote-tracking branch 'upstream/master' 98804c9 [Shuo Xiang] fix bug in topBykey and update test --- examples/src/main/python/ml/logistic_regression.py | 67 ++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 examples/src/main/python/ml/logistic_regression.py (limited to 'examples/src/main/python') diff --git a/examples/src/main/python/ml/logistic_regression.py b/examples/src/main/python/ml/logistic_regression.py new file mode 100644 index 0000000000..55afe1b207 --- /dev/null +++ b/examples/src/main/python/ml/logistic_regression.py @@ -0,0 +1,67 @@ +# +# 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. +# + +from __future__ import print_function + +import sys + +from pyspark import SparkContext +from pyspark.ml.classification import LogisticRegression +from pyspark.mllib.evaluation import MulticlassMetrics +from pyspark.ml.feature import StringIndexer +from pyspark.mllib.util import MLUtils +from pyspark.sql import SQLContext + +""" +A simple example demonstrating a logistic regression with elastic net regularization Pipeline. +Run with: + bin/spark-submit examples/src/main/python/ml/logistic_regression.py +""" + +if __name__ == "__main__": + + if len(sys.argv) > 1: + print("Usage: logistic_regression", file=sys.stderr) + exit(-1) + + sc = SparkContext(appName="PythonLogisticRegressionExample") + sqlContext = SQLContext(sc) + + # Load and parse the data file into a dataframe. + df = MLUtils.loadLibSVMFile(sc, "data/mllib/sample_libsvm_data.txt").toDF() + + # Map labels into an indexed column of labels in [0, numLabels) + stringIndexer = StringIndexer(inputCol="label", outputCol="indexedLabel") + si_model = stringIndexer.fit(df) + td = si_model.transform(df) + [training, test] = td.randomSplit([0.7, 0.3]) + + lr = LogisticRegression(maxIter=100, regParam=0.3).setLabelCol("indexedLabel") + lr.setElasticNetParam(0.8) + + # Fit the model + lrModel = lr.fit(training) + + predictionAndLabels = lrModel.transform(test).select("prediction", "indexedLabel") \ + .map(lambda x: (x.prediction, x.indexedLabel)) + + metrics = MulticlassMetrics(predictionAndLabels) + print("weighted f-measure %.3f" % metrics.weightedFMeasure()) + print("precision %s" % metrics.precision()) + print("recall %s" % metrics.recall()) + + sc.stop() -- cgit v1.2.3