StringIndexer (Spark 3.5.5 JavaDoc) (original) (raw)
Object
- org.apache.spark.ml.PipelineStage
- org.apache.spark.ml.Estimator<StringIndexerModel>
- org.apache.spark.ml.feature.StringIndexer
- org.apache.spark.ml.Estimator<StringIndexerModel>
All Implemented Interfaces:
java.io.Serializable, org.apache.spark.internal.Logging, StringIndexerBase, Params, HasHandleInvalid, HasInputCol, HasInputCols, HasOutputCol, HasOutputCols, DefaultParamsWritable, Identifiable, MLWritable
public class StringIndexer
extends Estimator<StringIndexerModel>
implements StringIndexerBase, DefaultParamsWritable
A label indexer that maps string column(s) of labels to ML column(s) of label indices. If the input columns are numeric, we cast them to string and index the string values. The indices are in [0, numLabels). By default, this is ordered by label frequencies so the most frequent label gets index 0. The ordering behavior is controlled by setting stringOrderType.
See Also:IndexToString for the inverse transformation, Serialized Form
Nested Class Summary
* ### Nested classes/interfaces inherited from interface org.apache.spark.internal.Logging `org.apache.spark.internal.Logging.SparkShellLoggingFilter`Constructor Summary
Constructors
Constructor and Description StringIndexer() StringIndexer(String uid) Method Summary
All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type Method and Description StringIndexer copy(ParamMap extra) Creates a copy of this instance with the same UID and some extra params. StringIndexerModel fit(Dataset<?> dataset) Fits a model to the input data. Param handleInvalid() Param for how to handle invalid data (unseen labels or NULL values). Param inputCol() Param for input column name. StringArrayParam inputCols() Param for input column names. static StringIndexer load(String path) Param outputCol() Param for output column name. StringArrayParam outputCols() Param for output column names. static MLReader read() StringIndexer setHandleInvalid(String value) StringIndexer setInputCol(String value) StringIndexer setInputCols(String[] value) StringIndexer setOutputCol(String value) StringIndexer setOutputCols(String[] value) StringIndexer setStringOrderType(String value) Param stringOrderType() Param for how to order labels of string column. StructType transformSchema(StructType schema) Check transform validity and derive the output schema from the input schema. String uid() An immutable unique ID for the object and its derivatives. * ### Methods inherited from class org.apache.spark.ml.[Estimator](../../../../../org/apache/spark/ml/Estimator.html "class in org.apache.spark.ml") `[fit](../../../../../org/apache/spark/ml/Estimator.html#fit-org.apache.spark.sql.Dataset-org.apache.spark.ml.param.ParamMap-), [fit](../../../../../org/apache/spark/ml/Estimator.html#fit-org.apache.spark.sql.Dataset-org.apache.spark.ml.param.ParamPair-org.apache.spark.ml.param.ParamPair...-), [fit](../../../../../org/apache/spark/ml/Estimator.html#fit-org.apache.spark.sql.Dataset-org.apache.spark.ml.param.ParamPair-scala.collection.Seq-), [fit](../../../../../org/apache/spark/ml/Estimator.html#fit-org.apache.spark.sql.Dataset-scala.collection.Seq-)` * ### Methods inherited from class org.apache.spark.ml.[PipelineStage](../../../../../org/apache/spark/ml/PipelineStage.html "class in org.apache.spark.ml") `[params](../../../../../org/apache/spark/ml/PipelineStage.html#params--)` * ### Methods inherited from class Object `equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait` * ### Methods inherited from interface org.apache.spark.ml.feature.[StringIndexerBase](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html "interface in org.apache.spark.ml.feature") `[getInOutCols](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html#getInOutCols--), [getStringOrderType](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html#getStringOrderType--), [validateAndTransformField](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html#validateAndTransformField-org.apache.spark.sql.types.StructType-java.lang.String-java.lang.String-), [validateAndTransformSchema](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html#validateAndTransformSchema-org.apache.spark.sql.types.StructType-boolean-)` * ### Methods inherited from interface org.apache.spark.ml.param.shared.[HasHandleInvalid](../../../../../org/apache/spark/ml/param/shared/HasHandleInvalid.html "interface in org.apache.spark.ml.param.shared") `[getHandleInvalid](../../../../../org/apache/spark/ml/param/shared/HasHandleInvalid.html#getHandleInvalid--)` * ### Methods inherited from interface org.apache.spark.ml.param.shared.[HasInputCol](../../../../../org/apache/spark/ml/param/shared/HasInputCol.html "interface in org.apache.spark.ml.param.shared") `[getInputCol](../../../../../org/apache/spark/ml/param/shared/HasInputCol.html#getInputCol--)` * ### Methods inherited from interface org.apache.spark.ml.param.shared.[HasOutputCol](../../../../../org/apache/spark/ml/param/shared/HasOutputCol.html "interface in org.apache.spark.ml.param.shared") `[getOutputCol](../../../../../org/apache/spark/ml/param/shared/HasOutputCol.html#getOutputCol--)` * ### Methods inherited from interface org.apache.spark.ml.param.shared.[HasInputCols](../../../../../org/apache/spark/ml/param/shared/HasInputCols.html "interface in org.apache.spark.ml.param.shared") `[getInputCols](../../../../../org/apache/spark/ml/param/shared/HasInputCols.html#getInputCols--)` * ### Methods inherited from interface org.apache.spark.ml.param.shared.[HasOutputCols](../../../../../org/apache/spark/ml/param/shared/HasOutputCols.html "interface in org.apache.spark.ml.param.shared") `[getOutputCols](../../../../../org/apache/spark/ml/param/shared/HasOutputCols.html#getOutputCols--)` * ### Methods inherited from interface org.apache.spark.ml.param.[Params](../../../../../org/apache/spark/ml/param/Params.html "interface in org.apache.spark.ml.param") `[clear](../../../../../org/apache/spark/ml/param/Params.html#clear-org.apache.spark.ml.param.Param-), [copyValues](../../../../../org/apache/spark/ml/param/Params.html#copyValues-T-org.apache.spark.ml.param.ParamMap-), [defaultCopy](../../../../../org/apache/spark/ml/param/Params.html#defaultCopy-org.apache.spark.ml.param.ParamMap-), [defaultParamMap](../../../../../org/apache/spark/ml/param/Params.html#defaultParamMap--), [explainParam](../../../../../org/apache/spark/ml/param/Params.html#explainParam-org.apache.spark.ml.param.Param-), [explainParams](../../../../../org/apache/spark/ml/param/Params.html#explainParams--), [extractParamMap](../../../../../org/apache/spark/ml/param/Params.html#extractParamMap--), [extractParamMap](../../../../../org/apache/spark/ml/param/Params.html#extractParamMap-org.apache.spark.ml.param.ParamMap-), [get](../../../../../org/apache/spark/ml/param/Params.html#get-org.apache.spark.ml.param.Param-), [getDefault](../../../../../org/apache/spark/ml/param/Params.html#getDefault-org.apache.spark.ml.param.Param-), [getOrDefault](../../../../../org/apache/spark/ml/param/Params.html#getOrDefault-org.apache.spark.ml.param.Param-), [getParam](../../../../../org/apache/spark/ml/param/Params.html#getParam-java.lang.String-), [hasDefault](../../../../../org/apache/spark/ml/param/Params.html#hasDefault-org.apache.spark.ml.param.Param-), [hasParam](../../../../../org/apache/spark/ml/param/Params.html#hasParam-java.lang.String-), [isDefined](../../../../../org/apache/spark/ml/param/Params.html#isDefined-org.apache.spark.ml.param.Param-), [isSet](../../../../../org/apache/spark/ml/param/Params.html#isSet-org.apache.spark.ml.param.Param-), [onParamChange](../../../../../org/apache/spark/ml/param/Params.html#onParamChange-org.apache.spark.ml.param.Param-), [paramMap](../../../../../org/apache/spark/ml/param/Params.html#paramMap--), [params](../../../../../org/apache/spark/ml/param/Params.html#params--), [set](../../../../../org/apache/spark/ml/param/Params.html#set-org.apache.spark.ml.param.Param-T-), [set](../../../../../org/apache/spark/ml/param/Params.html#set-org.apache.spark.ml.param.ParamPair-), [set](../../../../../org/apache/spark/ml/param/Params.html#set-java.lang.String-java.lang.Object-), [setDefault](../../../../../org/apache/spark/ml/param/Params.html#setDefault-org.apache.spark.ml.param.Param-T-), [setDefault](../../../../../org/apache/spark/ml/param/Params.html#setDefault-scala.collection.Seq-), [shouldOwn](../../../../../org/apache/spark/ml/param/Params.html#shouldOwn-org.apache.spark.ml.param.Param-)` * ### Methods inherited from interface org.apache.spark.ml.util.[Identifiable](../../../../../org/apache/spark/ml/util/Identifiable.html "interface in org.apache.spark.ml.util") `[toString](../../../../../org/apache/spark/ml/util/Identifiable.html#toString--)` * ### Methods inherited from interface org.apache.spark.ml.util.[DefaultParamsWritable](../../../../../org/apache/spark/ml/util/DefaultParamsWritable.html "interface in org.apache.spark.ml.util") `[write](../../../../../org/apache/spark/ml/util/DefaultParamsWritable.html#write--)` * ### Methods inherited from interface org.apache.spark.ml.util.[MLWritable](../../../../../org/apache/spark/ml/util/MLWritable.html "interface in org.apache.spark.ml.util") `[save](../../../../../org/apache/spark/ml/util/MLWritable.html#save-java.lang.String-)` * ### Methods inherited from interface org.apache.spark.internal.Logging `$init$, initializeForcefully, initializeLogIfNecessary, initializeLogIfNecessary, initializeLogIfNecessary$default$2, initLock, isTraceEnabled, log, logDebug, logDebug, logError, logError, logInfo, logInfo, logName, logTrace, logTrace, logWarning, logWarning, org$apache$spark$internal$Logging$$log__$eq, org$apache$spark$internal$Logging$$log_, uninitialize`Constructor Detail
* #### StringIndexer public StringIndexer(String uid) * #### StringIndexer public StringIndexer()Method Detail
* #### load public static [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") load(String path) * #### read public static [MLReader](../../../../../org/apache/spark/ml/util/MLReader.html "class in org.apache.spark.ml.util")<T> read() * #### handleInvalid public [Param](../../../../../org/apache/spark/ml/param/Param.html "class in org.apache.spark.ml.param")<String> handleInvalid() Param for how to handle invalid data (unseen labels or NULL values). 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](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html#handleInvalid--)` in interface `[StringIndexerBase](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html "interface in org.apache.spark.ml.feature")` Specified by: `[handleInvalid](../../../../../org/apache/spark/ml/param/shared/HasHandleInvalid.html#handleInvalid--)` in interface `[HasHandleInvalid](../../../../../org/apache/spark/ml/param/shared/HasHandleInvalid.html "interface in org.apache.spark.ml.param.shared")` Returns: (undocumented) * #### stringOrderType public final [Param](../../../../../org/apache/spark/ml/param/Param.html "class in org.apache.spark.ml.param")<String> stringOrderType() Param for how to order labels of string column. The first label after ordering is assigned an index of 0\. Options are: - 'frequencyDesc': descending order by label frequency (most frequent label assigned 0) - 'frequencyAsc': ascending order by label frequency (least frequent label assigned 0) - 'alphabetDesc': descending alphabetical order - 'alphabetAsc': ascending alphabetical order Default is 'frequencyDesc'. Note: In case of equal frequency when under frequencyDesc/Asc, the strings are further sorted alphabetically. Specified by: `[stringOrderType](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html#stringOrderType--)` in interface `[StringIndexerBase](../../../../../org/apache/spark/ml/feature/StringIndexerBase.html "interface in org.apache.spark.ml.feature")` Returns: (undocumented) * #### outputCols public final [StringArrayParam](../../../../../org/apache/spark/ml/param/StringArrayParam.html "class in org.apache.spark.ml.param") outputCols() Param for output column names. Specified by: `[outputCols](../../../../../org/apache/spark/ml/param/shared/HasOutputCols.html#outputCols--)` in interface `[HasOutputCols](../../../../../org/apache/spark/ml/param/shared/HasOutputCols.html "interface in org.apache.spark.ml.param.shared")` Returns: (undocumented) * #### inputCols public final [StringArrayParam](../../../../../org/apache/spark/ml/param/StringArrayParam.html "class in org.apache.spark.ml.param") inputCols() Param for input column names. Specified by: `[inputCols](../../../../../org/apache/spark/ml/param/shared/HasInputCols.html#inputCols--)` in interface `[HasInputCols](../../../../../org/apache/spark/ml/param/shared/HasInputCols.html "interface in org.apache.spark.ml.param.shared")` Returns: (undocumented) * #### outputCol public final [Param](../../../../../org/apache/spark/ml/param/Param.html "class in org.apache.spark.ml.param")<String> outputCol() Param for output column name. Specified by: `[outputCol](../../../../../org/apache/spark/ml/param/shared/HasOutputCol.html#outputCol--)` in interface `[HasOutputCol](../../../../../org/apache/spark/ml/param/shared/HasOutputCol.html "interface in org.apache.spark.ml.param.shared")` Returns: (undocumented) * #### inputCol public final [Param](../../../../../org/apache/spark/ml/param/Param.html "class in org.apache.spark.ml.param")<String> inputCol() Description copied from interface: `[HasInputCol](../../../../../org/apache/spark/ml/param/shared/HasInputCol.html#inputCol--)` Param for input column name. Specified by: `[inputCol](../../../../../org/apache/spark/ml/param/shared/HasInputCol.html#inputCol--)` in interface `[HasInputCol](../../../../../org/apache/spark/ml/param/shared/HasInputCol.html "interface in org.apache.spark.ml.param.shared")` Returns: (undocumented) * #### uid public String uid() An immutable unique ID for the object and its derivatives. Specified by: `[uid](../../../../../org/apache/spark/ml/util/Identifiable.html#uid--)` in interface `[Identifiable](../../../../../org/apache/spark/ml/util/Identifiable.html "interface in org.apache.spark.ml.util")` Returns: (undocumented) * #### setHandleInvalid public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") setHandleInvalid(String value) * #### setStringOrderType public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") setStringOrderType(String value) * #### setInputCol public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") setInputCol(String value) * #### setOutputCol public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") setOutputCol(String value) * #### setInputCols public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") setInputCols(String[] value) * #### setOutputCols public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") setOutputCols(String[] value) * #### fit public [StringIndexerModel](../../../../../org/apache/spark/ml/feature/StringIndexerModel.html "class in org.apache.spark.ml.feature") fit([Dataset](../../../../../org/apache/spark/sql/Dataset.html "class in org.apache.spark.sql")<?> dataset) Description copied from class: `[Estimator](../../../../../org/apache/spark/ml/Estimator.html#fit-org.apache.spark.sql.Dataset-)` Fits a model to the input data. Specified by: `[fit](../../../../../org/apache/spark/ml/Estimator.html#fit-org.apache.spark.sql.Dataset-)` in class `[Estimator](../../../../../org/apache/spark/ml/Estimator.html "class in org.apache.spark.ml")<[StringIndexerModel](../../../../../org/apache/spark/ml/feature/StringIndexerModel.html "class in org.apache.spark.ml.feature")>` Parameters: `dataset` \- (undocumented) Returns: (undocumented) * #### transformSchema public [StructType](../../../../../org/apache/spark/sql/types/StructType.html "class in org.apache.spark.sql.types") transformSchema([StructType](../../../../../org/apache/spark/sql/types/StructType.html "class in org.apache.spark.sql.types") schema) 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](../../../../../org/apache/spark/ml/PipelineStage.html#transformSchema-org.apache.spark.sql.types.StructType-)` in class `[PipelineStage](../../../../../org/apache/spark/ml/PipelineStage.html "class in org.apache.spark.ml")` Parameters: `schema` \- (undocumented) Returns: (undocumented) * #### copy public [StringIndexer](../../../../../org/apache/spark/ml/feature/StringIndexer.html "class in org.apache.spark.ml.feature") copy([ParamMap](../../../../../org/apache/spark/ml/param/ParamMap.html "class in org.apache.spark.ml.param") extra) Description copied from interface: `[Params](../../../../../org/apache/spark/ml/param/Params.html#copy-org.apache.spark.ml.param.ParamMap-)` 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](../../../../../org/apache/spark/ml/param/Params.html#copy-org.apache.spark.ml.param.ParamMap-)` in interface `[Params](../../../../../org/apache/spark/ml/param/Params.html "interface in org.apache.spark.ml.param")` Specified by: `[copy](../../../../../org/apache/spark/ml/Estimator.html#copy-org.apache.spark.ml.param.ParamMap-)` in class `[Estimator](../../../../../org/apache/spark/ml/Estimator.html "class in org.apache.spark.ml")<[StringIndexerModel](../../../../../org/apache/spark/ml/feature/StringIndexerModel.html "class in org.apache.spark.ml.feature")>` Parameters: `extra` \- (undocumented) Returns: (undocumented)