Package org.apache.spark.ml.feature

Class IndexToString

Object
org.apache.spark.ml.PipelineStage
org.apache.spark.ml.Transformer
org.apache.spark.ml.feature.IndexToString
All Implemented Interfaces:
Serializable, org.apache.spark.internal.Logging, Params, HasInputCol, HasOutputCol, DefaultParamsWritable, Identifiable, MLWritable
public class IndexToString extends Transformer implements HasInputCol, HasOutputCol, DefaultParamsWritable
A Transformer that maps a column of indices back to a new column of corresponding string values. The index-string mapping is either from the ML attributes of the input column, or from user-supplied labels (which take precedence over ML attributes).

See Also:

  • Constructor Details

    • IndexToString

      public IndexToString(String uid)

    • IndexToString

      public IndexToString()

  • Method Details

    • load

      public static IndexToString load(String path)

    • read

      public static MLReader<T> read()

    • outputCol

      public final Param<String> outputCol()
      Description copied from interface: HasOutputCol
      Param for output column name.
      Specified by:
      outputCol in interface HasOutputCol
      Returns:
      (undocumented)

    • inputCol

      public final Param<String> inputCol()
      Description copied from interface: HasInputCol
      Param for input column name.
      Specified by:
      inputCol in interface HasInputCol
      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)

    • setInputCol

      public IndexToString setInputCol(String value)

    • setOutputCol

      public IndexToString setOutputCol(String value)

    • setLabels

      public IndexToString setLabels(String[] value)

    • labels

      public final StringArrayParam labels()
      Optional param for array of labels specifying index-string mapping.

      Default: Not specified, in which case inputCol() metadata is used for labels.

      Returns:
      (undocumented)

    • getLabels

      public final String[] getLabels()

    • 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)

    • 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)

    • copy

      public IndexToString 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 Transformer
      Parameters:
      extra - (undocumented)
      Returns:
      (undocumented)