org.apache.spark.ml.feature

Interface RFormulaBase

All Superinterfaces:

HasFeaturesCol, HasHandleInvalid, HasLabelCol, Identifiable, Params, java.io.Serializable

All Known Implementing Classes:

RFormula, RFormulaModel

public interface RFormulaBase
extends HasFeaturesCol, HasLabelCol, HasHandleInvalid

Base trait for RFormula and RFormulaModel.

Method Summary

Modifier and Type	Method and Description
BooleanParam	forceIndexLabel() Force to index label whether it is numeric or string type.
Param<String>	formula() R formula parameter.
boolean	getForceIndexLabel()
String	getFormula()
String	getStringIndexerOrderType()
Param<String>	handleInvalid() Param for how to handle invalid data (unseen or NULL values) in features and label column of string type.
boolean	hasLabelCol(StructType schema)
Param<String>	stringIndexerOrderType() Param for how to order categories of a string FEATURE column used by StringIndexer.

Methods inherited from interface org.apache.spark.ml.param.shared.HasFeaturesCol

featuresCol, getFeaturesCol

Methods inherited from interface org.apache.spark.ml.param.shared.HasLabelCol

getLabelCol, labelCol

Methods inherited from interface org.apache.spark.ml.param.shared.HasHandleInvalid

getHandleInvalid

Methods inherited from interface org.apache.spark.ml.param.Params

clear, copy, copyValues, defaultCopy, defaultParamMap, explainParam, explainParams, extractParamMap, extractParamMap, get, getDefault, getOrDefault, getParam, hasDefault, hasParam, isDefined, isSet, onParamChange, paramMap, params, set, set, set, setDefault, setDefault, shouldOwn

Methods inherited from interface org.apache.spark.ml.util.Identifiable

toString, uid

Method Detail

forceIndexLabel

BooleanParam forceIndexLabel()

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.

Returns:

(undocumented)

formula

Param<String> formula()

R formula parameter. The formula is provided in string form.

Returns:

(undocumented)

getForceIndexLabel

boolean getForceIndexLabel()

getFormula

String getFormula()

getStringIndexerOrderType

String getStringIndexerOrderType()

handleInvalid

Param<String> handleInvalid()

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

Returns:

(undocumented)

hasLabelCol

boolean hasLabelCol(StructType schema)

stringIndexerOrderType

Param<String> stringIndexerOrderType()

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.

Returns:

(undocumented)