[SPARK-22289] Cannot save LogisticRegressionModel with bounds on coefficients

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.2.0
• Fix Version/s: 2.2.2, 2.3.0
• Component/s: ML
• Assignee: yuhao yang
• Reporter: Nic Eggert
• Shepherd: Yanbo Liang
• Created: 16/Oct/17 20:46
• Updated: 08/Feb/18 01:32
• Resolved: 12/Dec/17 19:28

Description

I think this was introduced in SPARK-20047.

Trying to call save on a logistic regression model trained with bounds on its parameters throws an error. This seems to be because Spark doesn't know how to serialize the Matrix parameter.

Model is set up like this:

    val calibrator = new LogisticRegression()
      .setFeaturesCol("uncalibrated_probability")
      .setLabelCol("label")
      .setWeightCol("weight")
      .setStandardization(false)
      .setLowerBoundsOnCoefficients(new DenseMatrix(1, 1, Array(0.0)))
      .setFamily("binomial")
      .setProbabilityCol("probability")
      .setPredictionCol("logistic_prediction")
      .setRawPredictionCol("logistic_raw_prediction")

17/10/16 15:36:59 ERROR ApplicationMaster: User class threw exception: scala.NotImplementedError: The default jsonEncode only supports string and vector. org.apache.spark.ml.param.Param must override jsonEncode for org.apache.spark.ml.linalg.DenseMatrix.
scala.NotImplementedError: The default jsonEncode only supports string and vector. org.apache.spark.ml.param.Param must override jsonEncode for org.apache.spark.ml.linalg.DenseMatrix.
	at org.apache.spark.ml.param.Param.jsonEncode(params.scala:98)
	at org.apache.spark.ml.util.DefaultParamsWriter$$anonfun$1$$anonfun$2.apply(ReadWrite.scala:296)
	at org.apache.spark.ml.util.DefaultParamsWriter$$anonfun$1$$anonfun$2.apply(ReadWrite.scala:295)
	at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
	at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
	at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
	at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
	at scala.collection.TraversableLike$class.map(TraversableLike.scala:234)
	at scala.collection.AbstractTraversable.map(Traversable.scala:104)
	at org.apache.spark.ml.util.DefaultParamsWriter$$anonfun$1.apply(ReadWrite.scala:295)
	at org.apache.spark.ml.util.DefaultParamsWriter$$anonfun$1.apply(ReadWrite.scala:295)
	at scala.Option.getOrElse(Option.scala:121)
	at org.apache.spark.ml.util.DefaultParamsWriter$.getMetadataToSave(ReadWrite.scala:295)
	at org.apache.spark.ml.util.DefaultParamsWriter$.saveMetadata(ReadWrite.scala:277)
	at org.apache.spark.ml.classification.LogisticRegressionModel$LogisticRegressionModelWriter.saveImpl(LogisticRegression.scala:1182)
	at org.apache.spark.ml.util.MLWriter.save(ReadWrite.scala:114)
	at org.apache.spark.ml.Pipeline$SharedReadWrite$$anonfun$saveImpl$1.apply(Pipeline.scala:254)
	at org.apache.spark.ml.Pipeline$SharedReadWrite$$anonfun$saveImpl$1.apply(Pipeline.scala:253)
	at scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33)
	at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:186)
	at org.apache.spark.ml.Pipeline$SharedReadWrite$.saveImpl(Pipeline.scala:253)
	at org.apache.spark.ml.PipelineModel$PipelineModelWriter.saveImpl(Pipeline.scala:337)
	at org.apache.spark.ml.util.MLWriter.save(ReadWrite.scala:114)
	-snip-

Issue Links

• links to: [Github] Pull Request #19525 (hhbyyh)