Package org.apache.spark.ml.feature

Class RFormulaModel

Object
org.apache.spark.ml.PipelineStage
org.apache.spark.ml.Transformer
org.apache.spark.ml.Model<RFormulaModel>
org.apache.spark.ml.feature.RFormulaModel
All Implemented Interfaces:
Serializable, org.apache.spark.internal.Logging, RFormulaBase, Params, HasFeaturesCol, HasHandleInvalid, HasLabelCol, Identifiable, MLWritable, scala.Serializable
public class RFormulaModel extends Model<RFormulaModel> implements RFormulaBase, MLWritable
Model fitted by RFormula. Fitting is required to determine the factor levels of formula terms.

param: resolvedFormula the fitted R formula. param: pipelineModel the fitted feature model, including factor to index mappings.

See Also:

  • Method Details

    • read

      public static MLReader<RFormulaModel> read()

    • load

      public static RFormulaModel load(String path)

    • formula

      public Param<String> formula()
      Description copied from interface: RFormulaBase
      R formula parameter. The formula is provided in string form.
      Specified by:
      formula in interface RFormulaBase
      Returns:
      (undocumented)

    • forceIndexLabel

      public BooleanParam forceIndexLabel()
      Description copied from interface: RFormulaBase
      Force to index label whether it is numeric or string type. Usually we index label only when it is string type. If the formula was used by classification algorithms, we can force to index label even it is numeric type by setting this param with true. Default: false.
      Specified by:
      forceIndexLabel in interface RFormulaBase
      Returns:
      (undocumented)

    • handleInvalid

      public Param<String> handleInvalid()
      Description copied from interface: RFormulaBase
      Param for how to handle invalid data (unseen or NULL values) in features and label column of string type. Options are 'skip' (filter out rows with invalid data), 'error' (throw an error), or 'keep' (put invalid data in a special additional bucket, at index numLabels). Default: "error"
      Specified by:
      handleInvalid in interface HasHandleInvalid
      Specified by:
      handleInvalid in interface RFormulaBase
      Returns:
      (undocumented)

    • stringIndexerOrderType

      public final Param<String> stringIndexerOrderType()
      Description copied from interface: RFormulaBase
      Param for how to order categories of a string FEATURE column used by StringIndexer. The last category after ordering is dropped when encoding strings. Supported options: 'frequencyDesc', 'frequencyAsc', 'alphabetDesc', 'alphabetAsc'. The default value is 'frequencyDesc'. When the ordering is set to 'alphabetDesc', RFormula drops the same category as R when encoding strings.

      The options are explained using an example 'b', 'a', 'b', 'a', 'c', 'b': 

      
 +-----------------+---------------------------------------+----------------------------------+
 |      Option     | Category mapped to 0 by StringIndexer |  Category dropped by RFormula    |
 +-----------------+---------------------------------------+----------------------------------+
 | 'frequencyDesc' | most frequent category ('b')          | least frequent category ('c')    |
 | 'frequencyAsc'  | least frequent category ('c')         | most frequent category ('b')     |
 | 'alphabetDesc'  | last alphabetical category ('c')      | first alphabetical category ('a')|
 | 'alphabetAsc'   | first alphabetical category ('a')     | last alphabetical category ('c') |
 +-----------------+---------------------------------------+----------------------------------+
      Note that this ordering option is NOT used for the label column. When the label column is indexed, it uses the default descending frequency ordering in StringIndexer.

      Specified by:
      stringIndexerOrderType in interface RFormulaBase
      Returns:
      (undocumented)

    • labelCol

      public final Param<String> labelCol()
      Description copied from interface: HasLabelCol
      Param for label column name.
      Specified by:
      labelCol in interface HasLabelCol
      Returns:
      (undocumented)

    • featuresCol

      public final Param<String> featuresCol()
      Description copied from interface: HasFeaturesCol
      Param for features column name.
      Specified by:
      featuresCol in interface HasFeaturesCol
      Returns:
      (undocumented)

    • uid

      public String uid()
      Description copied from interface: Identifiable
      An immutable unique ID for the object and its derivatives.
      Specified by:
      uid in interface Identifiable
      Returns:
      (undocumented)

    • transform

      public Dataset<Row> transform(Dataset<?> dataset)
      Description copied from class: Transformer
      Transforms the input dataset.
      Specified by:
      transform in class Transformer
      Parameters:
      dataset - (undocumented)
      Returns:
      (undocumented)

    • transformSchema

      public StructType transformSchema(StructType schema)
      Description copied from class: PipelineStage
      Check transform validity and derive the output schema from the input schema.

      We check validity for interactions between parameters during transformSchema and raise an exception if any parameter value is invalid. Parameter value checks which do not depend on other parameters are handled by Param.validate().

      Typical implementation should first conduct verification on schema change and parameter validity, including complex parameter interaction checks.

      Specified by:
      transformSchema in class PipelineStage
      Parameters:
      schema - (undocumented)
      Returns:
      (undocumented)

    • copy

      public RFormulaModel copy(ParamMap extra)
      Description copied from interface: Params
      Creates a copy of this instance with the same UID and some extra params. Subclasses should implement this method and set the return type properly. See defaultCopy().
      Specified by:
      copy in interface Params
      Specified by:
      copy in class Model<RFormulaModel>
      Parameters:
      extra - (undocumented)
      Returns:
      (undocumented)

    • toString

      public String toString()
      Specified by:
      toString in interface Identifiable
      Overrides:
      toString in class Object

    • write

      public MLWriter write()
      Description copied from interface: MLWritable
      Returns an MLWriter instance for this ML instance.
      Specified by:
      write in interface MLWritable
      Returns:
      (undocumented)