Repository: spark Updated Branches: refs/heads/master 8bcad28a5 -> 3e3c3d58d
[SPARK-13706][ML] Add Python Example for Train Validation Split ## What changes were proposed in this pull request? This pull request adds a python example for train validation split. ## How was this patch tested? This was style tested through lint-python, generally tested with ./dev/run-tests, and run in notebook and shell environments. It was viewed in docs locally with jekyll serve. This contribution is my original work and I license it to Spark under its open source license. Author: JeremyNixon <jnix...@gmail.com> Closes #11547 from JeremyNixon/tvs_example. Project: http://git-wip-us.apache.org/repos/asf/spark/repo Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/3e3c3d58 Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/3e3c3d58 Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/3e3c3d58 Branch: refs/heads/master Commit: 3e3c3d58d8d42b42e930d42eb70b0e84d02967eb Parents: 8bcad28 Author: JeremyNixon <jnix...@gmail.com> Authored: Thu Mar 10 09:09:56 2016 +0200 Committer: Nick Pentreath <nick.pentre...@gmail.com> Committed: Thu Mar 10 09:18:15 2016 +0200 ---------------------------------------------------------------------- docs/ml-guide.md | 4 ++ .../main/python/ml/train_validation_split.py | 68 ++++++++++++++++++++ 2 files changed, 72 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/spark/blob/3e3c3d58/docs/ml-guide.md ---------------------------------------------------------------------- diff --git a/docs/ml-guide.md b/docs/ml-guide.md index a5a825f6..9916787 100644 --- a/docs/ml-guide.md +++ b/docs/ml-guide.md @@ -316,4 +316,8 @@ The `ParamMap` which produces the best evaluation metric is selected as the best {% include_example java/org/apache/spark/examples/ml/JavaModelSelectionViaTrainValidationSplitExample.java %} </div> +<div data-lang="python"> +{% include_example python/ml/train_validation_split.py %} +</div> + </div> http://git-wip-us.apache.org/repos/asf/spark/blob/3e3c3d58/examples/src/main/python/ml/train_validation_split.py ---------------------------------------------------------------------- diff --git a/examples/src/main/python/ml/train_validation_split.py b/examples/src/main/python/ml/train_validation_split.py new file mode 100644 index 0000000..161a200 --- /dev/null +++ b/examples/src/main/python/ml/train_validation_split.py @@ -0,0 +1,68 @@ +# +# 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 pyspark import SparkContext +# $example on$ +from pyspark.ml.evaluation import RegressionEvaluator +from pyspark.ml.regression import LinearRegression +from pyspark.ml.tuning import ParamGridBuilder, TrainValidationSplit +from pyspark.sql import SQLContext +# $example off$ + +""" +This example demonstrates applying TrainValidationSplit to split data +and preform model selection. +Run with: + + bin/spark-submit examples/src/main/python/ml/train_validation_split.py +""" + +if __name__ == "__main__": + sc = SparkContext(appName="TrainValidationSplit") + sqlContext = SQLContext(sc) + # $example on$ + # Prepare training and test data. + data = sqlContext.read.format("libsvm")\ + .load("data/mllib/sample_linear_regression_data.txt") + train, test = data.randomSplit([0.7, 0.3]) + lr = LinearRegression(maxIter=10, regParam=0.1) + + # We use a ParamGridBuilder to construct a grid of parameters to search over. + # TrainValidationSplit will try all combinations of values and determine best model using + # the evaluator. + paramGrid = ParamGridBuilder()\ + .addGrid(lr.regParam, [0.1, 0.01]) \ + .addGrid(lr.elasticNetParam, [0.0, 0.5, 1.0])\ + .build() + + # In this case the estimator is simply the linear regression. + # A TrainValidationSplit requires an Estimator, a set of Estimator ParamMaps, and an Evaluator. + tvs = TrainValidationSplit(estimator=lr, + estimatorParamMaps=paramGrid, + evaluator=RegressionEvaluator(), + # 80% of the data will be used for training, 20% for validation. + trainRatio=0.8) + + # Run TrainValidationSplit, and choose the best set of parameters. + model = tvs.fit(train) + # Make predictions on test data. model is the model with combination of parameters + # that performed best. + prediction = model.transform(test) + for row in prediction.take(5): + print(row) + # $example off$ + sc.stop() --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@spark.apache.org For additional commands, e-mail: commits-h...@spark.apache.org
