public class OneHotEncoder extends Transformer
[0.0, 0.0, 1.0, 0.0]
.
The last category is not included by default (configurable via OneHotEncoder!.dropLast
because it makes the vector entries sum up to one, and hence linearly dependent.
So an input value of 4.0 maps to [0.0, 0.0, 0.0, 0.0]
.
Note that this is different from scikit-learn's OneHotEncoder, which keeps all categories.
The output vectors are sparse.
StringIndexer} for converting categorical values into category indices
,
Serialized FormConstructor and Description |
---|
OneHotEncoder() |
OneHotEncoder(String uid) |
Modifier and Type | Method and Description |
---|---|
BooleanParam |
dropLast()
Whether to drop the last category in the encoded vector (default: true)
|
OneHotEncoder |
setDropLast(boolean value) |
OneHotEncoder |
setInputCol(String value) |
OneHotEncoder |
setOutputCol(String value) |
DataFrame |
transform(DataFrame dataset)
Transforms the input dataset.
|
StructType |
transformSchema(StructType schema)
:: DeveloperApi ::
|
String |
uid() |
copy, transform, transform, transform
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
clear, copyValues, defaultParamMap, explainParam, explainParams, extractParamMap, extractParamMap, get, getDefault, getOrDefault, getParam, hasDefault, hasParam, isDefined, isSet, paramMap, params, set, set, set, setDefault, setDefault, setDefault, shouldOwn, validateParams
initializeIfNecessary, initializeLogging, isTraceEnabled, log_, log, logDebug, logDebug, logError, logError, logInfo, logInfo, logName, logTrace, logTrace, logWarning, logWarning
public OneHotEncoder(String uid)
public OneHotEncoder()
public String uid()
public final BooleanParam dropLast()
public OneHotEncoder setDropLast(boolean value)
public OneHotEncoder setInputCol(String value)
public OneHotEncoder setOutputCol(String value)
public StructType transformSchema(StructType schema)
PipelineStage
Derives the output schema from the input schema.
transformSchema
in class PipelineStage
schema
- (undocumented)public DataFrame transform(DataFrame dataset)
Transformer
transform
in class Transformer
dataset
- (undocumented)