org.jpmml.evaluator

Interface Evaluator

All Superinterfaces:

Consumer, Serializable

All Known Implementing Classes:

AssociationModelEvaluator, ClusteringModelEvaluator, GeneralRegressionModelEvaluator, MiningModelEvaluator, ModelEvaluator, NaiveBayesModelEvaluator, NearestNeighborModelEvaluator, NeuralNetworkEvaluator, RegressionModelEvaluator, RuleSetModelEvaluator, ScorecardEvaluator, SupportVectorMachineModelEvaluator, TreeModelEvaluator

public interface Evaluator
extends Consumer

Performs the evaluation of a Model in "interpreted mode".

Obtaining and verifying an Evaluator instance

 PMML pmml = ...;
 PMMLManager pmmlManager = new PMMLManager(pmml);
 Evaluator evaluator = (Evaluator)pmmlManager.getModelManager(ModelEvaluatorFactory.getInstance());
 evaluator.verify();
 

Preparing arguments

Converting an user-supplied map of arguments to a prepared map of arguments:

 Map<FieldName, ?> userArguments = ...;
 Map<FieldName, FieldValue> arguments = new LinkedHashMap<FieldName, FieldValue>();
 List<FieldName> activeFields = evaluator.getActiveFields();
 for(FieldName activeField : activeFields){
   FieldValue activeValue = evaluator.prepare(activeField, userArguments.get(activeField));
   arguments.put(activeField, activeValue);
 }
 

Performing the evaluation

 Map<FieldName, ?> result = evaluator.evaluate(arguments);
 

Processing results

Retrieving the value of the target field (ie. the primary result):

 FieldName targetField = evaluator.getTargetField();
 Object targetValue = result.get(targetField);
 

Decoding a complex value to a Java primitive value:

 if(targetValue instanceof Computable){
   Computable computable = (Computable)targetValue;

   targetValue = computable.getResult();
 }
 

Retrieving the values of output fields (ie. secondary results):

 List<FieldName> outputFields = evaluator.getOutputFields();
 for(FieldName outputField : outputFields){
   Object outputValue = result.get(outputField);
 }
 

See Also:

EvaluatorUtil

Method Summary

Methods

Modifier and Type	Method and Description
Map<org.dmg.pmml.FieldName,?>	evaluate(Map<org.dmg.pmml.FieldName,?> arguments) Evaluates the model with the specified arguments.
FieldValue	prepare(org.dmg.pmml.FieldName name, Object value) Prepares the input value for a field.
void	verify() Verifies the model.

Methods inherited from interface org.jpmml.manager.Consumer

getActiveFields, getDataField, getGroupFields, getMiningField, getOrderFields, getOutputField, getOutputFields, getSummary, getTargetField, getTargetFields

Method Detail

prepare

FieldValue prepare(org.dmg.pmml.FieldName name,
                 Object value)

Prepares the input value for a field. First, the value is converted from the user-supplied representation to internal representation. Later on, the value is subjected to missing value treatment, invalid value treatment and outlier treatment.

Parameters:

name - The name of the field

string - The input value in user-supplied representation. Use null to represent a missing input value.

Throws:

PMMLException - If the input value preparation fails.

See Also:

Consumer.getDataField(FieldName), Consumer.getMiningField(FieldName)

verify

void verify()

Verifies the model.

Throws:

PMMLException - If the verification fails.

evaluate

Map<org.dmg.pmml.FieldName,?> evaluate(Map<org.dmg.pmml.FieldName,?> arguments)

Evaluates the model with the specified arguments.

Parameters:

arguments - Map of active field values.

Returns:

Map of target field and output field values. Simple values are represented using the Java equivalents of PMML data types (eg. String, Integer, Float, Double etc.). Complex values are represented as instances of Computable that return simple values. A missing result is represented by null.

Throws:

PMMLException - If the evaluation fails. This is either InvalidFeatureException or UnsupportedFeatureException if there is a persistent structural problem with the PMML class model. This is EvaluationException (or one of its subclasses) if there is a problem with the evaluation request (eg. badly prepared arguments).

See Also:

Computable