Source code for pyspark.ml.classification

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import os
import operator
import sys
import uuid
import warnings
from abc import ABCMeta, abstractmethod, abstractproperty
from multiprocessing.pool import ThreadPool

from pyspark import keyword_only, since, SparkContext
from pyspark.ml import Estimator, Predictor, PredictionModel, Model
from pyspark.ml.param.shared import HasRawPredictionCol, HasProbabilityCol, HasThresholds, \
    HasRegParam, HasMaxIter, HasFitIntercept, HasTol, HasStandardization, HasWeightCol, \
    HasAggregationDepth, HasThreshold, HasBlockSize, HasMaxBlockSizeInMB, Param, Params, \
    TypeConverters, HasElasticNetParam, HasSeed, HasStepSize, HasSolver, HasParallelism
from pyspark.ml.tree import _DecisionTreeModel, _DecisionTreeParams, \
    _TreeEnsembleModel, _RandomForestParams, _GBTParams, \
    _HasVarianceImpurity, _TreeClassifierParams
from pyspark.ml.regression import _FactorizationMachinesParams, DecisionTreeRegressionModel
from pyspark.ml.base import _PredictorParams
from pyspark.ml.util import DefaultParamsReader, DefaultParamsWriter, \
    JavaMLReadable, JavaMLReader, JavaMLWritable, JavaMLWriter, \
    MLReader, MLReadable, MLWriter, MLWritable, HasTrainingSummary
from pyspark.ml.wrapper import JavaParams, \
    JavaPredictor, JavaPredictionModel, JavaWrapper
from pyspark.ml.common import inherit_doc
from pyspark.ml.linalg import Vectors
from pyspark.sql import DataFrame
from pyspark.sql.functions import udf, when
from pyspark.sql.types import ArrayType, DoubleType
from pyspark.storagelevel import StorageLevel

__all__ = ['LinearSVC', 'LinearSVCModel',
           'LinearSVCSummary', 'LinearSVCTrainingSummary',
           'LogisticRegression', 'LogisticRegressionModel',
           'LogisticRegressionSummary', 'LogisticRegressionTrainingSummary',
           'BinaryLogisticRegressionSummary', 'BinaryLogisticRegressionTrainingSummary',
           'DecisionTreeClassifier', 'DecisionTreeClassificationModel',
           'GBTClassifier', 'GBTClassificationModel',
           'RandomForestClassifier', 'RandomForestClassificationModel',
           'RandomForestClassificationSummary', 'RandomForestClassificationTrainingSummary',
           'BinaryRandomForestClassificationSummary',
           'BinaryRandomForestClassificationTrainingSummary',
           'NaiveBayes', 'NaiveBayesModel',
           'MultilayerPerceptronClassifier', 'MultilayerPerceptronClassificationModel',
           'MultilayerPerceptronClassificationSummary',
           'MultilayerPerceptronClassificationTrainingSummary',
           'OneVsRest', 'OneVsRestModel',
           'FMClassifier', 'FMClassificationModel', 'FMClassificationSummary',
           'FMClassificationTrainingSummary']


class _ClassifierParams(HasRawPredictionCol, _PredictorParams):
    """
    Classifier Params for classification tasks.

    .. versionadded:: 3.0.0
    """
    pass


@inherit_doc
class Classifier(Predictor, _ClassifierParams, metaclass=ABCMeta):
    """
    Classifier for classification tasks.
    Classes are indexed {0, 1, ..., numClasses - 1}.
    """

    @since("3.0.0")
    def setRawPredictionCol(self, value):
        """
        Sets the value of :py:attr:`rawPredictionCol`.
        """
        return self._set(rawPredictionCol=value)


@inherit_doc
class ClassificationModel(PredictionModel, _ClassifierParams, metaclass=ABCMeta):
    """
    Model produced by a ``Classifier``.
    Classes are indexed {0, 1, ..., numClasses - 1}.
    """

    @since("3.0.0")
    def setRawPredictionCol(self, value):
        """
        Sets the value of :py:attr:`rawPredictionCol`.
        """
        return self._set(rawPredictionCol=value)

    @abstractproperty
    @since("2.1.0")
    def numClasses(self):
        """
        Number of classes (values which the label can take).
        """
        raise NotImplementedError()

    @abstractmethod
    @since("3.0.0")
    def predictRaw(self, value):
        """
        Raw prediction for each possible label.
        """
        raise NotImplementedError()


class _ProbabilisticClassifierParams(HasProbabilityCol, HasThresholds, _ClassifierParams):
    """
    Params for :py:class:`ProbabilisticClassifier` and
    :py:class:`ProbabilisticClassificationModel`.

    .. versionadded:: 3.0.0
    """
    pass


@inherit_doc
class ProbabilisticClassifier(Classifier, _ProbabilisticClassifierParams,
                              metaclass=ABCMeta):
    """
    Probabilistic Classifier for classification tasks.
    """

    @since("3.0.0")
    def setProbabilityCol(self, value):
        """
        Sets the value of :py:attr:`probabilityCol`.
        """
        return self._set(probabilityCol=value)

    @since("3.0.0")
    def setThresholds(self, value):
        """
        Sets the value of :py:attr:`thresholds`.
        """
        return self._set(thresholds=value)


@inherit_doc
class ProbabilisticClassificationModel(ClassificationModel,
                                       _ProbabilisticClassifierParams,
                                       metaclass=ABCMeta):
    """
    Model produced by a ``ProbabilisticClassifier``.
    """

    @since("3.0.0")
    def setProbabilityCol(self, value):
        """
        Sets the value of :py:attr:`probabilityCol`.
        """
        return self._set(probabilityCol=value)

    @since("3.0.0")
    def setThresholds(self, value):
        """
        Sets the value of :py:attr:`thresholds`.
        """
        return self._set(thresholds=value)

    @abstractmethod
    @since("3.0.0")
    def predictProbability(self, value):
        """
        Predict the probability of each class given the features.
        """
        raise NotImplementedError()


@inherit_doc
class _JavaClassifier(Classifier, JavaPredictor, metaclass=ABCMeta):
    """
    Java Classifier for classification tasks.
    Classes are indexed {0, 1, ..., numClasses - 1}.
    """

    @since("3.0.0")
    def setRawPredictionCol(self, value):
        """
        Sets the value of :py:attr:`rawPredictionCol`.
        """
        return self._set(rawPredictionCol=value)


@inherit_doc
class _JavaClassificationModel(ClassificationModel, JavaPredictionModel):
    """
    Java Model produced by a ``Classifier``.
    Classes are indexed {0, 1, ..., numClasses - 1}.
    To be mixed in with :class:`pyspark.ml.JavaModel`
    """

    @property
    @since("2.1.0")
    def numClasses(self):
        """
        Number of classes (values which the label can take).
        """
        return self._call_java("numClasses")

    @since("3.0.0")
    def predictRaw(self, value):
        """
        Raw prediction for each possible label.
        """
        return self._call_java("predictRaw", value)


@inherit_doc
class _JavaProbabilisticClassifier(ProbabilisticClassifier, _JavaClassifier,
                                   metaclass=ABCMeta):
    """
    Java Probabilistic Classifier for classification tasks.
    """
    pass


@inherit_doc
class _JavaProbabilisticClassificationModel(ProbabilisticClassificationModel,
                                            _JavaClassificationModel):
    """
    Java Model produced by a ``ProbabilisticClassifier``.
    """

    @since("3.0.0")
    def predictProbability(self, value):
        """
        Predict the probability of each class given the features.
        """
        return self._call_java("predictProbability", value)


@inherit_doc
class _ClassificationSummary(JavaWrapper):
    """
    Abstraction for multiclass classification results for a given model.

    .. versionadded:: 3.1.0
    """

    @property
    @since("3.1.0")
    def predictions(self):
        """
        Dataframe outputted by the model's `transform` method.
        """
        return self._call_java("predictions")

    @property
    @since("3.1.0")
    def predictionCol(self):
        """
        Field in "predictions" which gives the prediction of each class.
        """
        return self._call_java("predictionCol")

    @property
    @since("3.1.0")
    def labelCol(self):
        """
        Field in "predictions" which gives the true label of each
        instance.
        """
        return self._call_java("labelCol")

    @property
    @since("3.1.0")
    def weightCol(self):
        """
        Field in "predictions" which gives the weight of each instance
        as a vector.
        """
        return self._call_java("weightCol")

    @property
    def labels(self):
        """
        Returns the sequence of labels in ascending order. This order matches the order used
        in metrics which are specified as arrays over labels, e.g., truePositiveRateByLabel.

        .. versionadded:: 3.1.0

        Notes
        -----
        In most cases, it will be values {0.0, 1.0, ..., numClasses-1}, However, if the
        training set is missing a label, then all of the arrays over labels
        (e.g., from truePositiveRateByLabel) will be of length numClasses-1 instead of the
        expected numClasses.
        """
        return self._call_java("labels")

    @property
    @since("3.1.0")
    def truePositiveRateByLabel(self):
        """
        Returns true positive rate for each label (category).
        """
        return self._call_java("truePositiveRateByLabel")

    @property
    @since("3.1.0")
    def falsePositiveRateByLabel(self):
        """
        Returns false positive rate for each label (category).
        """
        return self._call_java("falsePositiveRateByLabel")

    @property
    @since("3.1.0")
    def precisionByLabel(self):
        """
        Returns precision for each label (category).
        """
        return self._call_java("precisionByLabel")

    @property
    @since("3.1.0")
    def recallByLabel(self):
        """
        Returns recall for each label (category).
        """
        return self._call_java("recallByLabel")

    @since("3.1.0")
    def fMeasureByLabel(self, beta=1.0):
        """
        Returns f-measure for each label (category).
        """
        return self._call_java("fMeasureByLabel", beta)

    @property
    @since("3.1.0")
    def accuracy(self):
        """
        Returns accuracy.
        (equals to the total number of correctly classified instances
        out of the total number of instances.)
        """
        return self._call_java("accuracy")

    @property
    @since("3.1.0")
    def weightedTruePositiveRate(self):
        """
        Returns weighted true positive rate.
        (equals to precision, recall and f-measure)
        """
        return self._call_java("weightedTruePositiveRate")

    @property
    @since("3.1.0")
    def weightedFalsePositiveRate(self):
        """
        Returns weighted false positive rate.
        """
        return self._call_java("weightedFalsePositiveRate")

    @property
    @since("3.1.0")
    def weightedRecall(self):
        """
        Returns weighted averaged recall.
        (equals to precision, recall and f-measure)
        """
        return self._call_java("weightedRecall")

    @property
    @since("3.1.0")
    def weightedPrecision(self):
        """
        Returns weighted averaged precision.
        """
        return self._call_java("weightedPrecision")

    @since("3.1.0")
    def weightedFMeasure(self, beta=1.0):
        """
        Returns weighted averaged f-measure.
        """
        return self._call_java("weightedFMeasure", beta)


@inherit_doc
class _TrainingSummary(JavaWrapper):
    """
    Abstraction for Training results.

    .. versionadded:: 3.1.0
    """

    @property
    @since("3.1.0")
    def objectiveHistory(self):
        """
        Objective function (scaled loss + regularization) at each
        iteration. It contains one more element, the initial state,
        than number of iterations.
        """
        return self._call_java("objectiveHistory")

    @property
    @since("3.1.0")
    def totalIterations(self):
        """
        Number of training iterations until termination.
        """
        return self._call_java("totalIterations")


@inherit_doc
class _BinaryClassificationSummary(_ClassificationSummary):
    """
    Binary classification results for a given model.

    .. versionadded:: 3.1.0
    """

    @property
    @since("3.1.0")
    def scoreCol(self):
        """
        Field in "predictions" which gives the probability or raw prediction
        of each class as a vector.
        """
        return self._call_java("scoreCol")

    @property
    def roc(self):
        """
        Returns the receiver operating characteristic (ROC) curve,
        which is a Dataframe having two fields (FPR, TPR) with
        (0.0, 0.0) prepended and (1.0, 1.0) appended to it.

        .. versionadded:: 3.1.0

        Notes
        -----
        `Wikipedia reference <http://en.wikipedia.org/wiki/Receiver_operating_characteristic>`_
        """
        return self._call_java("roc")

    @property
    @since("3.1.0")
    def areaUnderROC(self):
        """
        Computes the area under the receiver operating characteristic
        (ROC) curve.
        """
        return self._call_java("areaUnderROC")

    @property
    @since("3.1.0")
    def pr(self):
        """
        Returns the precision-recall curve, which is a Dataframe
        containing two fields recall, precision with (0.0, 1.0) prepended
        to it.
        """
        return self._call_java("pr")

    @property
    @since("3.1.0")
    def fMeasureByThreshold(self):
        """
        Returns a dataframe with two fields (threshold, F-Measure) curve
        with beta = 1.0.
        """
        return self._call_java("fMeasureByThreshold")

    @property
    @since("3.1.0")
    def precisionByThreshold(self):
        """
        Returns a dataframe with two fields (threshold, precision) curve.
        Every possible probability obtained in transforming the dataset
        are used as thresholds used in calculating the precision.
        """
        return self._call_java("precisionByThreshold")

    @property
    @since("3.1.0")
    def recallByThreshold(self):
        """
        Returns a dataframe with two fields (threshold, recall) curve.
        Every possible probability obtained in transforming the dataset
        are used as thresholds used in calculating the recall.
        """
        return self._call_java("recallByThreshold")


class _LinearSVCParams(_ClassifierParams, HasRegParam, HasMaxIter, HasFitIntercept, HasTol,
                       HasStandardization, HasWeightCol, HasAggregationDepth, HasThreshold,
                       HasMaxBlockSizeInMB):
    """
    Params for :py:class:`LinearSVC` and :py:class:`LinearSVCModel`.

    .. versionadded:: 3.0.0
    """

    threshold = Param(Params._dummy(), "threshold",
                      "The threshold in binary classification applied to the linear model"
                      " prediction.  This threshold can be any real number, where Inf will make"
                      " all predictions 0.0 and -Inf will make all predictions 1.0.",
                      typeConverter=TypeConverters.toFloat)

    def __init__(self, *args):
        super(_LinearSVCParams, self).__init__(*args)
        self._setDefault(maxIter=100, regParam=0.0, tol=1e-6, fitIntercept=True,
                         standardization=True, threshold=0.0, aggregationDepth=2,
                         maxBlockSizeInMB=0.0)


[docs]@inherit_doc class LinearSVC(_JavaClassifier, _LinearSVCParams, JavaMLWritable, JavaMLReadable): """ This binary classifier optimizes the Hinge Loss using the OWLQN optimizer. Only supports L2 regularization currently. .. versionadded:: 2.2.0 Notes ----- `Linear SVM Classifier <https://en.wikipedia.org/wiki/Support_vector_machine#Linear_SVM>`_ Examples -------- >>> from pyspark.sql import Row >>> from pyspark.ml.linalg import Vectors >>> df = sc.parallelize([ ... Row(label=1.0, features=Vectors.dense(1.0, 1.0, 1.0)), ... Row(label=0.0, features=Vectors.dense(1.0, 2.0, 3.0))]).toDF() >>> svm = LinearSVC() >>> svm.getMaxIter() 100 >>> svm.setMaxIter(5) LinearSVC... >>> svm.getMaxIter() 5 >>> svm.getRegParam() 0.0 >>> svm.setRegParam(0.01) LinearSVC... >>> svm.getRegParam() 0.01 >>> model = svm.fit(df) >>> model.setPredictionCol("newPrediction") LinearSVCModel... >>> model.getPredictionCol() 'newPrediction' >>> model.setThreshold(0.5) LinearSVCModel... >>> model.getThreshold() 0.5 >>> model.getMaxBlockSizeInMB() 0.0 >>> model.coefficients DenseVector([0.0, -0.2792, -0.1833]) >>> model.intercept 1.0206118982229047 >>> model.numClasses 2 >>> model.numFeatures 3 >>> test0 = sc.parallelize([Row(features=Vectors.dense(-1.0, -1.0, -1.0))]).toDF() >>> model.predict(test0.head().features) 1.0 >>> model.predictRaw(test0.head().features) DenseVector([-1.4831, 1.4831]) >>> result = model.transform(test0).head() >>> result.newPrediction 1.0 >>> result.rawPrediction DenseVector([-1.4831, 1.4831]) >>> svm_path = temp_path + "/svm" >>> svm.save(svm_path) >>> svm2 = LinearSVC.load(svm_path) >>> svm2.getMaxIter() 5 >>> model_path = temp_path + "/svm_model" >>> model.save(model_path) >>> model2 = LinearSVCModel.load(model_path) >>> model.coefficients[0] == model2.coefficients[0] True >>> model.intercept == model2.intercept True >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxIter=100, regParam=0.0, tol=1e-6, rawPredictionCol="rawPrediction", fitIntercept=True, standardization=True, threshold=0.0, weightCol=None, aggregationDepth=2, maxBlockSizeInMB=0.0): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxIter=100, regParam=0.0, tol=1e-6, rawPredictionCol="rawPrediction", \ fitIntercept=True, standardization=True, threshold=0.0, weightCol=None, \ aggregationDepth=2, maxBlockSizeInMB=0.0): """ super(LinearSVC, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.LinearSVC", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("2.2.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxIter=100, regParam=0.0, tol=1e-6, rawPredictionCol="rawPrediction", fitIntercept=True, standardization=True, threshold=0.0, weightCol=None, aggregationDepth=2, maxBlockSizeInMB=0.0): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxIter=100, regParam=0.0, tol=1e-6, rawPredictionCol="rawPrediction", \ fitIntercept=True, standardization=True, threshold=0.0, weightCol=None, \ aggregationDepth=2, maxBlockSizeInMB=0.0): Sets params for Linear SVM Classifier. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return LinearSVCModel(java_model)
[docs] @since("2.2.0") def setMaxIter(self, value): """ Sets the value of :py:attr:`maxIter`. """ return self._set(maxIter=value)
[docs] @since("2.2.0") def setRegParam(self, value): """ Sets the value of :py:attr:`regParam`. """ return self._set(regParam=value)
[docs] @since("2.2.0") def setTol(self, value): """ Sets the value of :py:attr:`tol`. """ return self._set(tol=value)
[docs] @since("2.2.0") def setFitIntercept(self, value): """ Sets the value of :py:attr:`fitIntercept`. """ return self._set(fitIntercept=value)
[docs] @since("2.2.0") def setStandardization(self, value): """ Sets the value of :py:attr:`standardization`. """ return self._set(standardization=value)
[docs] @since("2.2.0") def setThreshold(self, value): """ Sets the value of :py:attr:`threshold`. """ return self._set(threshold=value)
[docs] @since("2.2.0") def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs] @since("2.2.0") def setAggregationDepth(self, value): """ Sets the value of :py:attr:`aggregationDepth`. """ return self._set(aggregationDepth=value)
[docs] @since("3.1.0") def setMaxBlockSizeInMB(self, value): """ Sets the value of :py:attr:`maxBlockSizeInMB`. """ return self._set(maxBlockSizeInMB=value)
[docs]class LinearSVCModel(_JavaClassificationModel, _LinearSVCParams, JavaMLWritable, JavaMLReadable, HasTrainingSummary): """ Model fitted by LinearSVC. .. versionadded:: 2.2.0 """
[docs] @since("3.0.0") def setThreshold(self, value): """ Sets the value of :py:attr:`threshold`. """ return self._set(threshold=value)
@property @since("2.2.0") def coefficients(self): """ Model coefficients of Linear SVM Classifier. """ return self._call_java("coefficients") @property @since("2.2.0") def intercept(self): """ Model intercept of Linear SVM Classifier. """ return self._call_java("intercept")
[docs] @since("3.1.0") def summary(self): """ Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model trained on the training set. An exception is thrown if `trainingSummary is None`. """ if self.hasSummary: return LinearSVCTrainingSummary(super(LinearSVCModel, self).summary) else: raise RuntimeError("No training summary available for this %s" % self.__class__.__name__)
[docs] def evaluate(self, dataset): """ Evaluates the model on a test dataset. .. versionadded:: 3.1.0 Parameters ---------- dataset : :py:class:`pyspark.sql.DataFrame` Test dataset to evaluate model on. """ if not isinstance(dataset, DataFrame): raise ValueError("dataset must be a DataFrame but got %s." % type(dataset)) java_lsvc_summary = self._call_java("evaluate", dataset) return LinearSVCSummary(java_lsvc_summary)
[docs]class LinearSVCSummary(_BinaryClassificationSummary): """ Abstraction for LinearSVC Results for a given model. .. versionadded:: 3.1.0 """ pass
[docs]@inherit_doc class LinearSVCTrainingSummary(LinearSVCSummary, _TrainingSummary): """ Abstraction for LinearSVC Training results. .. versionadded:: 3.1.0 """ pass
class _LogisticRegressionParams(_ProbabilisticClassifierParams, HasRegParam, HasElasticNetParam, HasMaxIter, HasFitIntercept, HasTol, HasStandardization, HasWeightCol, HasAggregationDepth, HasThreshold, HasMaxBlockSizeInMB): """ Params for :py:class:`LogisticRegression` and :py:class:`LogisticRegressionModel`. .. versionadded:: 3.0.0 """ threshold = Param(Params._dummy(), "threshold", "Threshold in binary classification prediction, in range [0, 1]." + " If threshold and thresholds are both set, they must match." + "e.g. if threshold is p, then thresholds must be equal to [1-p, p].", typeConverter=TypeConverters.toFloat) family = Param(Params._dummy(), "family", "The name of family which is a description of the label distribution to " + "be used in the model. Supported options: auto, binomial, multinomial", typeConverter=TypeConverters.toString) lowerBoundsOnCoefficients = Param(Params._dummy(), "lowerBoundsOnCoefficients", "The lower bounds on coefficients if fitting under bound " "constrained optimization. The bound matrix must be " "compatible with the shape " "(1, number of features) for binomial regression, or " "(number of classes, number of features) " "for multinomial regression.", typeConverter=TypeConverters.toMatrix) upperBoundsOnCoefficients = Param(Params._dummy(), "upperBoundsOnCoefficients", "The upper bounds on coefficients if fitting under bound " "constrained optimization. The bound matrix must be " "compatible with the shape " "(1, number of features) for binomial regression, or " "(number of classes, number of features) " "for multinomial regression.", typeConverter=TypeConverters.toMatrix) lowerBoundsOnIntercepts = Param(Params._dummy(), "lowerBoundsOnIntercepts", "The lower bounds on intercepts if fitting under bound " "constrained optimization. The bounds vector size must be" "equal with 1 for binomial regression, or the number of" "lasses for multinomial regression.", typeConverter=TypeConverters.toVector) upperBoundsOnIntercepts = Param(Params._dummy(), "upperBoundsOnIntercepts", "The upper bounds on intercepts if fitting under bound " "constrained optimization. The bound vector size must be " "equal with 1 for binomial regression, or the number of " "classes for multinomial regression.", typeConverter=TypeConverters.toVector) def __init__(self, *args): super(_LogisticRegressionParams, self).__init__(*args) self._setDefault(maxIter=100, regParam=0.0, tol=1E-6, threshold=0.5, family="auto", maxBlockSizeInMB=0.0) @since("1.4.0") def setThreshold(self, value): """ Sets the value of :py:attr:`threshold`. Clears value of :py:attr:`thresholds` if it has been set. """ self._set(threshold=value) self.clear(self.thresholds) return self @since("1.4.0") def getThreshold(self): """ Get threshold for binary classification. If :py:attr:`thresholds` is set with length 2 (i.e., binary classification), this returns the equivalent threshold: :math:`\\frac{1}{1 + \\frac{thresholds(0)}{thresholds(1)}}`. Otherwise, returns :py:attr:`threshold` if set or its default value if unset. """ self._checkThresholdConsistency() if self.isSet(self.thresholds): ts = self.getOrDefault(self.thresholds) if len(ts) != 2: raise ValueError("Logistic Regression getThreshold only applies to" + " binary classification, but thresholds has length != 2." + " thresholds: " + ",".join(ts)) return 1.0/(1.0 + ts[0]/ts[1]) else: return self.getOrDefault(self.threshold) @since("1.5.0") def setThresholds(self, value): """ Sets the value of :py:attr:`thresholds`. Clears value of :py:attr:`threshold` if it has been set. """ self._set(thresholds=value) self.clear(self.threshold) return self @since("1.5.0") def getThresholds(self): """ If :py:attr:`thresholds` is set, return its value. Otherwise, if :py:attr:`threshold` is set, return the equivalent thresholds for binary classification: (1-threshold, threshold). If neither are set, throw an error. """ self._checkThresholdConsistency() if not self.isSet(self.thresholds) and self.isSet(self.threshold): t = self.getOrDefault(self.threshold) return [1.0-t, t] else: return self.getOrDefault(self.thresholds) def _checkThresholdConsistency(self): if self.isSet(self.threshold) and self.isSet(self.thresholds): ts = self.getOrDefault(self.thresholds) if len(ts) != 2: raise ValueError("Logistic Regression getThreshold only applies to" + " binary classification, but thresholds has length != 2." + " thresholds: {0}".format(str(ts))) t = 1.0/(1.0 + ts[0]/ts[1]) t2 = self.getOrDefault(self.threshold) if abs(t2 - t) >= 1E-5: raise ValueError("Logistic Regression getThreshold found inconsistent values for" + " threshold (%g) and thresholds (equivalent to %g)" % (t2, t)) @since("2.1.0") def getFamily(self): """ Gets the value of :py:attr:`family` or its default value. """ return self.getOrDefault(self.family) @since("2.3.0") def getLowerBoundsOnCoefficients(self): """ Gets the value of :py:attr:`lowerBoundsOnCoefficients` """ return self.getOrDefault(self.lowerBoundsOnCoefficients) @since("2.3.0") def getUpperBoundsOnCoefficients(self): """ Gets the value of :py:attr:`upperBoundsOnCoefficients` """ return self.getOrDefault(self.upperBoundsOnCoefficients) @since("2.3.0") def getLowerBoundsOnIntercepts(self): """ Gets the value of :py:attr:`lowerBoundsOnIntercepts` """ return self.getOrDefault(self.lowerBoundsOnIntercepts) @since("2.3.0") def getUpperBoundsOnIntercepts(self): """ Gets the value of :py:attr:`upperBoundsOnIntercepts` """ return self.getOrDefault(self.upperBoundsOnIntercepts)
[docs]@inherit_doc class LogisticRegression(_JavaProbabilisticClassifier, _LogisticRegressionParams, JavaMLWritable, JavaMLReadable): """ Logistic regression. This class supports multinomial logistic (softmax) and binomial logistic regression. .. versionadded:: 1.3.0 Examples -------- >>> from pyspark.sql import Row >>> from pyspark.ml.linalg import Vectors >>> bdf = sc.parallelize([ ... Row(label=1.0, weight=1.0, features=Vectors.dense(0.0, 5.0)), ... Row(label=0.0, weight=2.0, features=Vectors.dense(1.0, 2.0)), ... Row(label=1.0, weight=3.0, features=Vectors.dense(2.0, 1.0)), ... Row(label=0.0, weight=4.0, features=Vectors.dense(3.0, 3.0))]).toDF() >>> blor = LogisticRegression(weightCol="weight") >>> blor.getRegParam() 0.0 >>> blor.setRegParam(0.01) LogisticRegression... >>> blor.getRegParam() 0.01 >>> blor.setMaxIter(10) LogisticRegression... >>> blor.getMaxIter() 10 >>> blor.clear(blor.maxIter) >>> blorModel = blor.fit(bdf) >>> blorModel.setFeaturesCol("features") LogisticRegressionModel... >>> blorModel.setProbabilityCol("newProbability") LogisticRegressionModel... >>> blorModel.getProbabilityCol() 'newProbability' >>> blorModel.getMaxBlockSizeInMB() 0.0 >>> blorModel.setThreshold(0.1) LogisticRegressionModel... >>> blorModel.getThreshold() 0.1 >>> blorModel.coefficients DenseVector([-1.080..., -0.646...]) >>> blorModel.intercept 3.112... >>> blorModel.evaluate(bdf).accuracy == blorModel.summary.accuracy True >>> data_path = "data/mllib/sample_multiclass_classification_data.txt" >>> mdf = spark.read.format("libsvm").load(data_path) >>> mlor = LogisticRegression(regParam=0.1, elasticNetParam=1.0, family="multinomial") >>> mlorModel = mlor.fit(mdf) >>> mlorModel.coefficientMatrix SparseMatrix(3, 4, [0, 1, 2, 3], [3, 2, 1], [1.87..., -2.75..., -0.50...], 1) >>> mlorModel.interceptVector DenseVector([0.04..., -0.42..., 0.37...]) >>> test0 = sc.parallelize([Row(features=Vectors.dense(-1.0, 1.0))]).toDF() >>> blorModel.predict(test0.head().features) 1.0 >>> blorModel.predictRaw(test0.head().features) DenseVector([-3.54..., 3.54...]) >>> blorModel.predictProbability(test0.head().features) DenseVector([0.028, 0.972]) >>> result = blorModel.transform(test0).head() >>> result.prediction 1.0 >>> result.newProbability DenseVector([0.02..., 0.97...]) >>> result.rawPrediction DenseVector([-3.54..., 3.54...]) >>> test1 = sc.parallelize([Row(features=Vectors.sparse(2, [0], [1.0]))]).toDF() >>> blorModel.transform(test1).head().prediction 1.0 >>> blor.setParams("vector") Traceback (most recent call last): ... TypeError: Method setParams forces keyword arguments. >>> lr_path = temp_path + "/lr" >>> blor.save(lr_path) >>> lr2 = LogisticRegression.load(lr_path) >>> lr2.getRegParam() 0.01 >>> model_path = temp_path + "/lr_model" >>> blorModel.save(model_path) >>> model2 = LogisticRegressionModel.load(model_path) >>> blorModel.coefficients[0] == model2.coefficients[0] True >>> blorModel.intercept == model2.intercept True >>> model2 LogisticRegressionModel: uid=..., numClasses=2, numFeatures=2 >>> blorModel.transform(test0).take(1) == model2.transform(test0).take(1) True """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxIter=100, regParam=0.0, elasticNetParam=0.0, tol=1e-6, fitIntercept=True, threshold=0.5, thresholds=None, probabilityCol="probability", rawPredictionCol="rawPrediction", standardization=True, weightCol=None, aggregationDepth=2, family="auto", lowerBoundsOnCoefficients=None, upperBoundsOnCoefficients=None, lowerBoundsOnIntercepts=None, upperBoundsOnIntercepts=None, maxBlockSizeInMB=0.0): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxIter=100, regParam=0.0, elasticNetParam=0.0, tol=1e-6, fitIntercept=True, \ threshold=0.5, thresholds=None, probabilityCol="probability", \ rawPredictionCol="rawPrediction", standardization=True, weightCol=None, \ aggregationDepth=2, family="auto", \ lowerBoundsOnCoefficients=None, upperBoundsOnCoefficients=None, \ lowerBoundsOnIntercepts=None, upperBoundsOnIntercepts=None, \ maxBlockSizeInMB=0.0): If the threshold and thresholds Params are both set, they must be equivalent. """ super(LogisticRegression, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.LogisticRegression", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs) self._checkThresholdConsistency()
[docs] @keyword_only @since("1.3.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxIter=100, regParam=0.0, elasticNetParam=0.0, tol=1e-6, fitIntercept=True, threshold=0.5, thresholds=None, probabilityCol="probability", rawPredictionCol="rawPrediction", standardization=True, weightCol=None, aggregationDepth=2, family="auto", lowerBoundsOnCoefficients=None, upperBoundsOnCoefficients=None, lowerBoundsOnIntercepts=None, upperBoundsOnIntercepts=None, maxBlockSizeInMB=0.0): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxIter=100, regParam=0.0, elasticNetParam=0.0, tol=1e-6, fitIntercept=True, \ threshold=0.5, thresholds=None, probabilityCol="probability", \ rawPredictionCol="rawPrediction", standardization=True, weightCol=None, \ aggregationDepth=2, family="auto", \ lowerBoundsOnCoefficients=None, upperBoundsOnCoefficients=None, \ lowerBoundsOnIntercepts=None, upperBoundsOnIntercepts=None, \ maxBlockSizeInMB=0.0): Sets params for logistic regression. If the threshold and thresholds Params are both set, they must be equivalent. """ kwargs = self._input_kwargs self._set(**kwargs) self._checkThresholdConsistency() return self
def _create_model(self, java_model): return LogisticRegressionModel(java_model)
[docs] @since("2.1.0") def setFamily(self, value): """ Sets the value of :py:attr:`family`. """ return self._set(family=value)
[docs] @since("2.3.0") def setLowerBoundsOnCoefficients(self, value): """ Sets the value of :py:attr:`lowerBoundsOnCoefficients` """ return self._set(lowerBoundsOnCoefficients=value)
[docs] @since("2.3.0") def setUpperBoundsOnCoefficients(self, value): """ Sets the value of :py:attr:`upperBoundsOnCoefficients` """ return self._set(upperBoundsOnCoefficients=value)
[docs] @since("2.3.0") def setLowerBoundsOnIntercepts(self, value): """ Sets the value of :py:attr:`lowerBoundsOnIntercepts` """ return self._set(lowerBoundsOnIntercepts=value)
[docs] @since("2.3.0") def setUpperBoundsOnIntercepts(self, value): """ Sets the value of :py:attr:`upperBoundsOnIntercepts` """ return self._set(upperBoundsOnIntercepts=value)
[docs] def setMaxIter(self, value): """ Sets the value of :py:attr:`maxIter`. """ return self._set(maxIter=value)
[docs] def setRegParam(self, value): """ Sets the value of :py:attr:`regParam`. """ return self._set(regParam=value)
[docs] def setTol(self, value): """ Sets the value of :py:attr:`tol`. """ return self._set(tol=value)
[docs] def setElasticNetParam(self, value): """ Sets the value of :py:attr:`elasticNetParam`. """ return self._set(elasticNetParam=value)
[docs] def setFitIntercept(self, value): """ Sets the value of :py:attr:`fitIntercept`. """ return self._set(fitIntercept=value)
[docs] def setStandardization(self, value): """ Sets the value of :py:attr:`standardization`. """ return self._set(standardization=value)
[docs] def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs] def setAggregationDepth(self, value): """ Sets the value of :py:attr:`aggregationDepth`. """ return self._set(aggregationDepth=value)
[docs] @since("3.1.0") def setMaxBlockSizeInMB(self, value): """ Sets the value of :py:attr:`maxBlockSizeInMB`. """ return self._set(maxBlockSizeInMB=value)
[docs]class LogisticRegressionModel(_JavaProbabilisticClassificationModel, _LogisticRegressionParams, JavaMLWritable, JavaMLReadable, HasTrainingSummary): """ Model fitted by LogisticRegression. .. versionadded:: 1.3.0 """ @property @since("2.0.0") def coefficients(self): """ Model coefficients of binomial logistic regression. An exception is thrown in the case of multinomial logistic regression. """ return self._call_java("coefficients") @property @since("1.4.0") def intercept(self): """ Model intercept of binomial logistic regression. An exception is thrown in the case of multinomial logistic regression. """ return self._call_java("intercept") @property @since("2.1.0") def coefficientMatrix(self): """ Model coefficients. """ return self._call_java("coefficientMatrix") @property @since("2.1.0") def interceptVector(self): """ Model intercept. """ return self._call_java("interceptVector") @property @since("2.0.0") def summary(self): """ Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model trained on the training set. An exception is thrown if `trainingSummary is None`. """ if self.hasSummary: if self.numClasses <= 2: return BinaryLogisticRegressionTrainingSummary(super(LogisticRegressionModel, self).summary) else: return LogisticRegressionTrainingSummary(super(LogisticRegressionModel, self).summary) else: raise RuntimeError("No training summary available for this %s" % self.__class__.__name__)
[docs] def evaluate(self, dataset): """ Evaluates the model on a test dataset. .. versionadded:: 2.0.0 Parameters ---------- dataset : :py:class:`pyspark.sql.DataFrame` Test dataset to evaluate model on. """ if not isinstance(dataset, DataFrame): raise ValueError("dataset must be a DataFrame but got %s." % type(dataset)) java_blr_summary = self._call_java("evaluate", dataset) if self.numClasses <= 2: return BinaryLogisticRegressionSummary(java_blr_summary) else: return LogisticRegressionSummary(java_blr_summary)
[docs]class LogisticRegressionSummary(_ClassificationSummary): """ Abstraction for Logistic Regression Results for a given model. .. versionadded:: 2.0.0 """ @property @since("2.0.0") def probabilityCol(self): """ Field in "predictions" which gives the probability of each class as a vector. """ return self._call_java("probabilityCol") @property @since("2.0.0") def featuresCol(self): """ Field in "predictions" which gives the features of each instance as a vector. """ return self._call_java("featuresCol")
[docs]@inherit_doc class LogisticRegressionTrainingSummary(LogisticRegressionSummary, _TrainingSummary): """ Abstraction for multinomial Logistic Regression Training results. .. versionadded:: 2.0.0 """ pass
[docs]@inherit_doc class BinaryLogisticRegressionSummary(_BinaryClassificationSummary, LogisticRegressionSummary): """ Binary Logistic regression results for a given model. .. versionadded:: 2.0.0 """ pass
[docs]@inherit_doc class BinaryLogisticRegressionTrainingSummary(BinaryLogisticRegressionSummary, LogisticRegressionTrainingSummary): """ Binary Logistic regression training results for a given model. .. versionadded:: 2.0.0 """ pass
@inherit_doc class _DecisionTreeClassifierParams(_DecisionTreeParams, _TreeClassifierParams): """ Params for :py:class:`DecisionTreeClassifier` and :py:class:`DecisionTreeClassificationModel`. """ def __init__(self, *args): super(_DecisionTreeClassifierParams, self).__init__(*args) self._setDefault(maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", leafCol="", minWeightFractionPerNode=0.0)
[docs]@inherit_doc class DecisionTreeClassifier(_JavaProbabilisticClassifier, _DecisionTreeClassifierParams, JavaMLWritable, JavaMLReadable): """ `Decision tree <http://en.wikipedia.org/wiki/Decision_tree_learning>`_ learning algorithm for classification. It supports both binary and multiclass labels, as well as both continuous and categorical features. .. versionadded:: 1.4.0 Examples -------- >>> from pyspark.ml.linalg import Vectors >>> from pyspark.ml.feature import StringIndexer >>> df = spark.createDataFrame([ ... (1.0, Vectors.dense(1.0)), ... (0.0, Vectors.sparse(1, [], []))], ["label", "features"]) >>> stringIndexer = StringIndexer(inputCol="label", outputCol="indexed") >>> si_model = stringIndexer.fit(df) >>> td = si_model.transform(df) >>> dt = DecisionTreeClassifier(maxDepth=2, labelCol="indexed", leafCol="leafId") >>> model = dt.fit(td) >>> model.getLabelCol() 'indexed' >>> model.setFeaturesCol("features") DecisionTreeClassificationModel... >>> model.numNodes 3 >>> model.depth 1 >>> model.featureImportances SparseVector(1, {0: 1.0}) >>> model.numFeatures 1 >>> model.numClasses 2 >>> print(model.toDebugString) DecisionTreeClassificationModel...depth=1, numNodes=3... >>> test0 = spark.createDataFrame([(Vectors.dense(-1.0),)], ["features"]) >>> model.predict(test0.head().features) 0.0 >>> model.predictRaw(test0.head().features) DenseVector([1.0, 0.0]) >>> model.predictProbability(test0.head().features) DenseVector([1.0, 0.0]) >>> result = model.transform(test0).head() >>> result.prediction 0.0 >>> result.probability DenseVector([1.0, 0.0]) >>> result.rawPrediction DenseVector([1.0, 0.0]) >>> result.leafId 0.0 >>> test1 = spark.createDataFrame([(Vectors.sparse(1, [0], [1.0]),)], ["features"]) >>> model.transform(test1).head().prediction 1.0 >>> dtc_path = temp_path + "/dtc" >>> dt.save(dtc_path) >>> dt2 = DecisionTreeClassifier.load(dtc_path) >>> dt2.getMaxDepth() 2 >>> model_path = temp_path + "/dtc_model" >>> model.save(model_path) >>> model2 = DecisionTreeClassificationModel.load(model_path) >>> model.featureImportances == model2.featureImportances True >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True >>> df3 = spark.createDataFrame([ ... (1.0, 0.2, Vectors.dense(1.0)), ... (1.0, 0.8, Vectors.dense(1.0)), ... (0.0, 1.0, Vectors.sparse(1, [], []))], ["label", "weight", "features"]) >>> si3 = StringIndexer(inputCol="label", outputCol="indexed") >>> si_model3 = si3.fit(df3) >>> td3 = si_model3.transform(df3) >>> dt3 = DecisionTreeClassifier(maxDepth=2, weightCol="weight", labelCol="indexed") >>> model3 = dt3.fit(td3) >>> print(model3.toDebugString) DecisionTreeClassificationModel...depth=1, numNodes=3... """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", seed=None, weightCol=None, leafCol="", minWeightFractionPerNode=0.0): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", \ maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, \ maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", \ seed=None, weightCol=None, leafCol="", minWeightFractionPerNode=0.0) """ super(DecisionTreeClassifier, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.DecisionTreeClassifier", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("1.4.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", seed=None, weightCol=None, leafCol="", minWeightFractionPerNode=0.0): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", \ maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, \ maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", \ seed=None, weightCol=None, leafCol="", minWeightFractionPerNode=0.0) Sets params for the DecisionTreeClassifier. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return DecisionTreeClassificationModel(java_model)
[docs] def setMaxDepth(self, value): """ Sets the value of :py:attr:`maxDepth`. """ return self._set(maxDepth=value)
[docs] def setMaxBins(self, value): """ Sets the value of :py:attr:`maxBins`. """ return self._set(maxBins=value)
[docs] def setMinInstancesPerNode(self, value): """ Sets the value of :py:attr:`minInstancesPerNode`. """ return self._set(minInstancesPerNode=value)
[docs] @since("3.0.0") def setMinWeightFractionPerNode(self, value): """ Sets the value of :py:attr:`minWeightFractionPerNode`. """ return self._set(minWeightFractionPerNode=value)
[docs] def setMinInfoGain(self, value): """ Sets the value of :py:attr:`minInfoGain`. """ return self._set(minInfoGain=value)
[docs] def setMaxMemoryInMB(self, value): """ Sets the value of :py:attr:`maxMemoryInMB`. """ return self._set(maxMemoryInMB=value)
[docs] def setCacheNodeIds(self, value): """ Sets the value of :py:attr:`cacheNodeIds`. """ return self._set(cacheNodeIds=value)
[docs] @since("1.4.0") def setImpurity(self, value): """ Sets the value of :py:attr:`impurity`. """ return self._set(impurity=value)
[docs] @since("1.4.0") def setCheckpointInterval(self, value): """ Sets the value of :py:attr:`checkpointInterval`. """ return self._set(checkpointInterval=value)
[docs] def setSeed(self, value): """ Sets the value of :py:attr:`seed`. """ return self._set(seed=value)
[docs] @since("3.0.0") def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs]@inherit_doc class DecisionTreeClassificationModel(_DecisionTreeModel, _JavaProbabilisticClassificationModel, _DecisionTreeClassifierParams, JavaMLWritable, JavaMLReadable): """ Model fitted by DecisionTreeClassifier. .. versionadded:: 1.4.0 """ @property def featureImportances(self): """ Estimate of the importance of each feature. This generalizes the idea of "Gini" importance to other losses, following the explanation of Gini importance from "Random Forests" documentation by Leo Breiman and Adele Cutler, and following the implementation from scikit-learn. This feature importance is calculated as follows: - importance(feature j) = sum (over nodes which split on feature j) of the gain, where gain is scaled by the number of instances passing through node - Normalize importances for tree to sum to 1. .. versionadded:: 2.0.0 Notes ----- Feature importance for single decision trees can have high variance due to correlated predictor variables. Consider using a :py:class:`RandomForestClassifier` to determine feature importance instead. """ return self._call_java("featureImportances")
@inherit_doc class _RandomForestClassifierParams(_RandomForestParams, _TreeClassifierParams): """ Params for :py:class:`RandomForestClassifier` and :py:class:`RandomForestClassificationModel`. """ def __init__(self, *args): super(_RandomForestClassifierParams, self).__init__(*args) self._setDefault(maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", numTrees=20, featureSubsetStrategy="auto", subsamplingRate=1.0, leafCol="", minWeightFractionPerNode=0.0, bootstrap=True)
[docs]@inherit_doc class RandomForestClassifier(_JavaProbabilisticClassifier, _RandomForestClassifierParams, JavaMLWritable, JavaMLReadable): """ `Random Forest <http://en.wikipedia.org/wiki/Random_forest>`_ learning algorithm for classification. It supports both binary and multiclass labels, as well as both continuous and categorical features. .. versionadded:: 1.4.0 Examples -------- >>> import numpy >>> from numpy import allclose >>> from pyspark.ml.linalg import Vectors >>> from pyspark.ml.feature import StringIndexer >>> df = spark.createDataFrame([ ... (1.0, Vectors.dense(1.0)), ... (0.0, Vectors.sparse(1, [], []))], ["label", "features"]) >>> stringIndexer = StringIndexer(inputCol="label", outputCol="indexed") >>> si_model = stringIndexer.fit(df) >>> td = si_model.transform(df) >>> rf = RandomForestClassifier(numTrees=3, maxDepth=2, labelCol="indexed", seed=42, ... leafCol="leafId") >>> rf.getMinWeightFractionPerNode() 0.0 >>> model = rf.fit(td) >>> model.getLabelCol() 'indexed' >>> model.setFeaturesCol("features") RandomForestClassificationModel... >>> model.setRawPredictionCol("newRawPrediction") RandomForestClassificationModel... >>> model.getBootstrap() True >>> model.getRawPredictionCol() 'newRawPrediction' >>> model.featureImportances SparseVector(1, {0: 1.0}) >>> allclose(model.treeWeights, [1.0, 1.0, 1.0]) True >>> test0 = spark.createDataFrame([(Vectors.dense(-1.0),)], ["features"]) >>> model.predict(test0.head().features) 0.0 >>> model.predictRaw(test0.head().features) DenseVector([2.0, 0.0]) >>> model.predictProbability(test0.head().features) DenseVector([1.0, 0.0]) >>> result = model.transform(test0).head() >>> result.prediction 0.0 >>> numpy.argmax(result.probability) 0 >>> numpy.argmax(result.newRawPrediction) 0 >>> result.leafId DenseVector([0.0, 0.0, 0.0]) >>> test1 = spark.createDataFrame([(Vectors.sparse(1, [0], [1.0]),)], ["features"]) >>> model.transform(test1).head().prediction 1.0 >>> model.trees [DecisionTreeClassificationModel...depth=..., DecisionTreeClassificationModel...] >>> rfc_path = temp_path + "/rfc" >>> rf.save(rfc_path) >>> rf2 = RandomForestClassifier.load(rfc_path) >>> rf2.getNumTrees() 3 >>> model_path = temp_path + "/rfc_model" >>> model.save(model_path) >>> model2 = RandomForestClassificationModel.load(model_path) >>> model.featureImportances == model2.featureImportances True >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", numTrees=20, featureSubsetStrategy="auto", seed=None, subsamplingRate=1.0, leafCol="", minWeightFractionPerNode=0.0, weightCol=None, bootstrap=True): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", \ maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, \ maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, impurity="gini", \ numTrees=20, featureSubsetStrategy="auto", seed=None, subsamplingRate=1.0, \ leafCol="", minWeightFractionPerNode=0.0, weightCol=None, bootstrap=True) """ super(RandomForestClassifier, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.RandomForestClassifier", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("1.4.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, seed=None, impurity="gini", numTrees=20, featureSubsetStrategy="auto", subsamplingRate=1.0, leafCol="", minWeightFractionPerNode=0.0, weightCol=None, bootstrap=True): """ setParams(self, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", \ maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, \ maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, seed=None, \ impurity="gini", numTrees=20, featureSubsetStrategy="auto", subsamplingRate=1.0, \ leafCol="", minWeightFractionPerNode=0.0, weightCol=None, bootstrap=True) Sets params for linear classification. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return RandomForestClassificationModel(java_model)
[docs] def setMaxDepth(self, value): """ Sets the value of :py:attr:`maxDepth`. """ return self._set(maxDepth=value)
[docs] def setMaxBins(self, value): """ Sets the value of :py:attr:`maxBins`. """ return self._set(maxBins=value)
[docs] def setMinInstancesPerNode(self, value): """ Sets the value of :py:attr:`minInstancesPerNode`. """ return self._set(minInstancesPerNode=value)
[docs] def setMinInfoGain(self, value): """ Sets the value of :py:attr:`minInfoGain`. """ return self._set(minInfoGain=value)
[docs] def setMaxMemoryInMB(self, value): """ Sets the value of :py:attr:`maxMemoryInMB`. """ return self._set(maxMemoryInMB=value)
[docs] def setCacheNodeIds(self, value): """ Sets the value of :py:attr:`cacheNodeIds`. """ return self._set(cacheNodeIds=value)
[docs] @since("1.4.0") def setImpurity(self, value): """ Sets the value of :py:attr:`impurity`. """ return self._set(impurity=value)
[docs] @since("1.4.0") def setNumTrees(self, value): """ Sets the value of :py:attr:`numTrees`. """ return self._set(numTrees=value)
[docs] @since("3.0.0") def setBootstrap(self, value): """ Sets the value of :py:attr:`bootstrap`. """ return self._set(bootstrap=value)
[docs] @since("1.4.0") def setSubsamplingRate(self, value): """ Sets the value of :py:attr:`subsamplingRate`. """ return self._set(subsamplingRate=value)
[docs] @since("2.4.0") def setFeatureSubsetStrategy(self, value): """ Sets the value of :py:attr:`featureSubsetStrategy`. """ return self._set(featureSubsetStrategy=value)
[docs] def setSeed(self, value): """ Sets the value of :py:attr:`seed`. """ return self._set(seed=value)
[docs] def setCheckpointInterval(self, value): """ Sets the value of :py:attr:`checkpointInterval`. """ return self._set(checkpointInterval=value)
[docs] @since("3.0.0") def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs] @since("3.0.0") def setMinWeightFractionPerNode(self, value): """ Sets the value of :py:attr:`minWeightFractionPerNode`. """ return self._set(minWeightFractionPerNode=value)
[docs]class RandomForestClassificationModel(_TreeEnsembleModel, _JavaProbabilisticClassificationModel, _RandomForestClassifierParams, JavaMLWritable, JavaMLReadable, HasTrainingSummary): """ Model fitted by RandomForestClassifier. .. versionadded:: 1.4.0 """ @property def featureImportances(self): """ Estimate of the importance of each feature. Each feature's importance is the average of its importance across all trees in the ensemble The importance vector is normalized to sum to 1. This method is suggested by Hastie et al. (Hastie, Tibshirani, Friedman. "The Elements of Statistical Learning, 2nd Edition." 2001.) and follows the implementation from scikit-learn. .. versionadded:: 2.0.0 See Also -------- DecisionTreeClassificationModel.featureImportances """ return self._call_java("featureImportances") @property @since("2.0.0") def trees(self): """Trees in this ensemble. Warning: These have null parent Estimators.""" return [DecisionTreeClassificationModel(m) for m in list(self._call_java("trees"))] @property @since("3.1.0") def summary(self): """ Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model trained on the training set. An exception is thrown if `trainingSummary is None`. """ if self.hasSummary: if self.numClasses <= 2: return BinaryRandomForestClassificationTrainingSummary( super(RandomForestClassificationModel, self).summary) else: return RandomForestClassificationTrainingSummary( super(RandomForestClassificationModel, self).summary) else: raise RuntimeError("No training summary available for this %s" % self.__class__.__name__)
[docs] def evaluate(self, dataset): """ Evaluates the model on a test dataset. .. versionadded:: 3.1.0 Parameters ---------- dataset : :py:class:`pyspark.sql.DataFrame` Test dataset to evaluate model on. """ if not isinstance(dataset, DataFrame): raise ValueError("dataset must be a DataFrame but got %s." % type(dataset)) java_rf_summary = self._call_java("evaluate", dataset) if self.numClasses <= 2: return BinaryRandomForestClassificationSummary(java_rf_summary) else: return RandomForestClassificationSummary(java_rf_summary)
[docs]class RandomForestClassificationSummary(_ClassificationSummary): """ Abstraction for RandomForestClassification Results for a given model. .. versionadded:: 3.1.0 """ pass
[docs]@inherit_doc class RandomForestClassificationTrainingSummary(RandomForestClassificationSummary, _TrainingSummary): """ Abstraction for RandomForestClassificationTraining Training results. .. versionadded:: 3.1.0 """ pass
[docs]@inherit_doc class BinaryRandomForestClassificationSummary(_BinaryClassificationSummary): """ BinaryRandomForestClassification results for a given model. .. versionadded:: 3.1.0 """ pass
[docs]@inherit_doc class BinaryRandomForestClassificationTrainingSummary(BinaryRandomForestClassificationSummary, RandomForestClassificationTrainingSummary): """ BinaryRandomForestClassification training results for a given model. .. versionadded:: 3.1.0 """ pass
class _GBTClassifierParams(_GBTParams, _HasVarianceImpurity): """ Params for :py:class:`GBTClassifier` and :py:class:`GBTClassifierModel`. .. versionadded:: 3.0.0 """ supportedLossTypes = ["logistic"] lossType = Param(Params._dummy(), "lossType", "Loss function which GBT tries to minimize (case-insensitive). " + "Supported options: " + ", ".join(supportedLossTypes), typeConverter=TypeConverters.toString) def __init__(self, *args): super(_GBTClassifierParams, self).__init__(*args) self._setDefault(maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, lossType="logistic", maxIter=20, stepSize=0.1, subsamplingRate=1.0, impurity="variance", featureSubsetStrategy="all", validationTol=0.01, leafCol="", minWeightFractionPerNode=0.0) @since("1.4.0") def getLossType(self): """ Gets the value of lossType or its default value. """ return self.getOrDefault(self.lossType)
[docs]@inherit_doc class GBTClassifier(_JavaProbabilisticClassifier, _GBTClassifierParams, JavaMLWritable, JavaMLReadable): """ `Gradient-Boosted Trees (GBTs) <http://en.wikipedia.org/wiki/Gradient_boosting>`_ learning algorithm for classification. It supports binary labels, as well as both continuous and categorical features. .. versionadded:: 1.4.0 Notes ----- Multiclass labels are not currently supported. The implementation is based upon: J.H. Friedman. "Stochastic Gradient Boosting." 1999. Gradient Boosting vs. TreeBoost: - This implementation is for Stochastic Gradient Boosting, not for TreeBoost. - Both algorithms learn tree ensembles by minimizing loss functions. - TreeBoost (Friedman, 1999) additionally modifies the outputs at tree leaf nodes based on the loss function, whereas the original gradient boosting method does not. - We expect to implement TreeBoost in the future: `SPARK-4240 <https://issues.apache.org/jira/browse/SPARK-4240>`_ Examples -------- >>> from numpy import allclose >>> from pyspark.ml.linalg import Vectors >>> from pyspark.ml.feature import StringIndexer >>> df = spark.createDataFrame([ ... (1.0, Vectors.dense(1.0)), ... (0.0, Vectors.sparse(1, [], []))], ["label", "features"]) >>> stringIndexer = StringIndexer(inputCol="label", outputCol="indexed") >>> si_model = stringIndexer.fit(df) >>> td = si_model.transform(df) >>> gbt = GBTClassifier(maxIter=5, maxDepth=2, labelCol="indexed", seed=42, ... leafCol="leafId") >>> gbt.setMaxIter(5) GBTClassifier... >>> gbt.setMinWeightFractionPerNode(0.049) GBTClassifier... >>> gbt.getMaxIter() 5 >>> gbt.getFeatureSubsetStrategy() 'all' >>> model = gbt.fit(td) >>> model.getLabelCol() 'indexed' >>> model.setFeaturesCol("features") GBTClassificationModel... >>> model.setThresholds([0.3, 0.7]) GBTClassificationModel... >>> model.getThresholds() [0.3, 0.7] >>> model.featureImportances SparseVector(1, {0: 1.0}) >>> allclose(model.treeWeights, [1.0, 0.1, 0.1, 0.1, 0.1]) True >>> test0 = spark.createDataFrame([(Vectors.dense(-1.0),)], ["features"]) >>> model.predict(test0.head().features) 0.0 >>> model.predictRaw(test0.head().features) DenseVector([1.1697, -1.1697]) >>> model.predictProbability(test0.head().features) DenseVector([0.9121, 0.0879]) >>> result = model.transform(test0).head() >>> result.prediction 0.0 >>> result.leafId DenseVector([0.0, 0.0, 0.0, 0.0, 0.0]) >>> test1 = spark.createDataFrame([(Vectors.sparse(1, [0], [1.0]),)], ["features"]) >>> model.transform(test1).head().prediction 1.0 >>> model.totalNumNodes 15 >>> print(model.toDebugString) GBTClassificationModel...numTrees=5... >>> gbtc_path = temp_path + "gbtc" >>> gbt.save(gbtc_path) >>> gbt2 = GBTClassifier.load(gbtc_path) >>> gbt2.getMaxDepth() 2 >>> model_path = temp_path + "gbtc_model" >>> model.save(model_path) >>> model2 = GBTClassificationModel.load(model_path) >>> model.featureImportances == model2.featureImportances True >>> model.treeWeights == model2.treeWeights True >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True >>> model.trees [DecisionTreeRegressionModel...depth=..., DecisionTreeRegressionModel...] >>> validation = spark.createDataFrame([(0.0, Vectors.dense(-1.0),)], ... ["indexed", "features"]) >>> model.evaluateEachIteration(validation) [0.25..., 0.23..., 0.21..., 0.19..., 0.18...] >>> model.numClasses 2 >>> gbt = gbt.setValidationIndicatorCol("validationIndicator") >>> gbt.getValidationIndicatorCol() 'validationIndicator' >>> gbt.getValidationTol() 0.01 """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, lossType="logistic", maxIter=20, stepSize=0.1, seed=None, subsamplingRate=1.0, impurity="variance", featureSubsetStrategy="all", validationTol=0.01, validationIndicatorCol=None, leafCol="", minWeightFractionPerNode=0.0, weightCol=None): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, \ maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, \ lossType="logistic", maxIter=20, stepSize=0.1, seed=None, subsamplingRate=1.0, \ impurity="variance", featureSubsetStrategy="all", validationTol=0.01, \ validationIndicatorCol=None, leafCol="", minWeightFractionPerNode=0.0, \ weightCol=None) """ super(GBTClassifier, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.GBTClassifier", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("1.4.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, lossType="logistic", maxIter=20, stepSize=0.1, seed=None, subsamplingRate=1.0, impurity="variance", featureSubsetStrategy="all", validationTol=0.01, validationIndicatorCol=None, leafCol="", minWeightFractionPerNode=0.0, weightCol=None): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxDepth=5, maxBins=32, minInstancesPerNode=1, minInfoGain=0.0, \ maxMemoryInMB=256, cacheNodeIds=False, checkpointInterval=10, \ lossType="logistic", maxIter=20, stepSize=0.1, seed=None, subsamplingRate=1.0, \ impurity="variance", featureSubsetStrategy="all", validationTol=0.01, \ validationIndicatorCol=None, leafCol="", minWeightFractionPerNode=0.0, \ weightCol=None) Sets params for Gradient Boosted Tree Classification. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return GBTClassificationModel(java_model)
[docs] def setMaxDepth(self, value): """ Sets the value of :py:attr:`maxDepth`. """ return self._set(maxDepth=value)
[docs] def setMaxBins(self, value): """ Sets the value of :py:attr:`maxBins`. """ return self._set(maxBins=value)
[docs] def setMinInstancesPerNode(self, value): """ Sets the value of :py:attr:`minInstancesPerNode`. """ return self._set(minInstancesPerNode=value)
[docs] def setMinInfoGain(self, value): """ Sets the value of :py:attr:`minInfoGain`. """ return self._set(minInfoGain=value)
[docs] def setMaxMemoryInMB(self, value): """ Sets the value of :py:attr:`maxMemoryInMB`. """ return self._set(maxMemoryInMB=value)
[docs] def setCacheNodeIds(self, value): """ Sets the value of :py:attr:`cacheNodeIds`. """ return self._set(cacheNodeIds=value)
[docs] @since("1.4.0") def setImpurity(self, value): """ Sets the value of :py:attr:`impurity`. """ return self._set(impurity=value)
[docs] @since("1.4.0") def setLossType(self, value): """ Sets the value of :py:attr:`lossType`. """ return self._set(lossType=value)
[docs] @since("1.4.0") def setSubsamplingRate(self, value): """ Sets the value of :py:attr:`subsamplingRate`. """ return self._set(subsamplingRate=value)
[docs] @since("2.4.0") def setFeatureSubsetStrategy(self, value): """ Sets the value of :py:attr:`featureSubsetStrategy`. """ return self._set(featureSubsetStrategy=value)
[docs] @since("3.0.0") def setValidationIndicatorCol(self, value): """ Sets the value of :py:attr:`validationIndicatorCol`. """ return self._set(validationIndicatorCol=value)
[docs] @since("1.4.0") def setMaxIter(self, value): """ Sets the value of :py:attr:`maxIter`. """ return self._set(maxIter=value)
[docs] @since("1.4.0") def setCheckpointInterval(self, value): """ Sets the value of :py:attr:`checkpointInterval`. """ return self._set(checkpointInterval=value)
[docs] @since("1.4.0") def setSeed(self, value): """ Sets the value of :py:attr:`seed`. """ return self._set(seed=value)
[docs] @since("1.4.0") def setStepSize(self, value): """ Sets the value of :py:attr:`stepSize`. """ return self._set(stepSize=value)
[docs] @since("3.0.0") def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs] @since("3.0.0") def setMinWeightFractionPerNode(self, value): """ Sets the value of :py:attr:`minWeightFractionPerNode`. """ return self._set(minWeightFractionPerNode=value)
[docs]class GBTClassificationModel(_TreeEnsembleModel, _JavaProbabilisticClassificationModel, _GBTClassifierParams, JavaMLWritable, JavaMLReadable): """ Model fitted by GBTClassifier. .. versionadded:: 1.4.0 """ @property def featureImportances(self): """ Estimate of the importance of each feature. Each feature's importance is the average of its importance across all trees in the ensemble The importance vector is normalized to sum to 1. This method is suggested by Hastie et al. (Hastie, Tibshirani, Friedman. "The Elements of Statistical Learning, 2nd Edition." 2001.) and follows the implementation from scikit-learn. .. versionadded:: 2.0.0 See Also -------- DecisionTreeClassificationModel.featureImportances """ return self._call_java("featureImportances") @property @since("2.0.0") def trees(self): """Trees in this ensemble. Warning: These have null parent Estimators.""" return [DecisionTreeRegressionModel(m) for m in list(self._call_java("trees"))]
[docs] def evaluateEachIteration(self, dataset): """ Method to compute error or loss for every iteration of gradient boosting. .. versionadded:: 2.4.0 Parameters ---------- dataset : :py:class:`pyspark.sql.DataFrame` Test dataset to evaluate model on. """ return self._call_java("evaluateEachIteration", dataset)
class _NaiveBayesParams(_PredictorParams, HasWeightCol): """ Params for :py:class:`NaiveBayes` and :py:class:`NaiveBayesModel`. .. versionadded:: 3.0.0 """ smoothing = Param(Params._dummy(), "smoothing", "The smoothing parameter, should be >= 0, " + "default is 1.0", typeConverter=TypeConverters.toFloat) modelType = Param(Params._dummy(), "modelType", "The model type which is a string " + "(case-sensitive). Supported options: multinomial (default), bernoulli " + "and gaussian.", typeConverter=TypeConverters.toString) def __init__(self, *args): super(_NaiveBayesParams, self).__init__(*args) self._setDefault(smoothing=1.0, modelType="multinomial") @since("1.5.0") def getSmoothing(self): """ Gets the value of smoothing or its default value. """ return self.getOrDefault(self.smoothing) @since("1.5.0") def getModelType(self): """ Gets the value of modelType or its default value. """ return self.getOrDefault(self.modelType)
[docs]@inherit_doc class NaiveBayes(_JavaProbabilisticClassifier, _NaiveBayesParams, HasThresholds, HasWeightCol, JavaMLWritable, JavaMLReadable): """ Naive Bayes Classifiers. It supports both Multinomial and Bernoulli NB. `Multinomial NB \ <http://nlp.stanford.edu/IR-book/html/htmledition/naive-bayes-text-classification-1.html>`_ can handle finitely supported discrete data. For example, by converting documents into TF-IDF vectors, it can be used for document classification. By making every vector a binary (0/1) data, it can also be used as `Bernoulli NB \ <http://nlp.stanford.edu/IR-book/html/htmledition/the-bernoulli-model-1.html>`_. The input feature values for Multinomial NB and Bernoulli NB must be nonnegative. Since 3.0.0, it supports Complement NB which is an adaptation of the Multinomial NB. Specifically, Complement NB uses statistics from the complement of each class to compute the model's coefficients. The inventors of Complement NB show empirically that the parameter estimates for CNB are more stable than those for Multinomial NB. Like Multinomial NB, the input feature values for Complement NB must be nonnegative. Since 3.0.0, it also supports `Gaussian NB \ <https://en.wikipedia.org/wiki/Naive_Bayes_classifier#Gaussian_naive_Bayes>`_. which can handle continuous data. .. versionadded:: 1.5.0 Examples -------- >>> from pyspark.sql import Row >>> from pyspark.ml.linalg import Vectors >>> df = spark.createDataFrame([ ... Row(label=0.0, weight=0.1, features=Vectors.dense([0.0, 0.0])), ... Row(label=0.0, weight=0.5, features=Vectors.dense([0.0, 1.0])), ... Row(label=1.0, weight=1.0, features=Vectors.dense([1.0, 0.0]))]) >>> nb = NaiveBayes(smoothing=1.0, modelType="multinomial", weightCol="weight") >>> model = nb.fit(df) >>> model.setFeaturesCol("features") NaiveBayesModel... >>> model.getSmoothing() 1.0 >>> model.pi DenseVector([-0.81..., -0.58...]) >>> model.theta DenseMatrix(2, 2, [-0.91..., -0.51..., -0.40..., -1.09...], 1) >>> model.sigma DenseMatrix(0, 0, [...], ...) >>> test0 = sc.parallelize([Row(features=Vectors.dense([1.0, 0.0]))]).toDF() >>> model.predict(test0.head().features) 1.0 >>> model.predictRaw(test0.head().features) DenseVector([-1.72..., -0.99...]) >>> model.predictProbability(test0.head().features) DenseVector([0.32..., 0.67...]) >>> result = model.transform(test0).head() >>> result.prediction 1.0 >>> result.probability DenseVector([0.32..., 0.67...]) >>> result.rawPrediction DenseVector([-1.72..., -0.99...]) >>> test1 = sc.parallelize([Row(features=Vectors.sparse(2, [0], [1.0]))]).toDF() >>> model.transform(test1).head().prediction 1.0 >>> nb_path = temp_path + "/nb" >>> nb.save(nb_path) >>> nb2 = NaiveBayes.load(nb_path) >>> nb2.getSmoothing() 1.0 >>> model_path = temp_path + "/nb_model" >>> model.save(model_path) >>> model2 = NaiveBayesModel.load(model_path) >>> model.pi == model2.pi True >>> model.theta == model2.theta True >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True >>> nb = nb.setThresholds([0.01, 10.00]) >>> model3 = nb.fit(df) >>> result = model3.transform(test0).head() >>> result.prediction 0.0 >>> nb3 = NaiveBayes().setModelType("gaussian") >>> model4 = nb3.fit(df) >>> model4.getModelType() 'gaussian' >>> model4.sigma DenseMatrix(2, 2, [0.0, 0.25, 0.0, 0.0], 1) >>> nb5 = NaiveBayes(smoothing=1.0, modelType="complement", weightCol="weight") >>> model5 = nb5.fit(df) >>> model5.getModelType() 'complement' >>> model5.theta DenseMatrix(2, 2, [...], 1) >>> model5.sigma DenseMatrix(0, 0, [...], ...) """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", smoothing=1.0, modelType="multinomial", thresholds=None, weightCol=None): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", smoothing=1.0, \ modelType="multinomial", thresholds=None, weightCol=None) """ super(NaiveBayes, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.NaiveBayes", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("1.5.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", smoothing=1.0, modelType="multinomial", thresholds=None, weightCol=None): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", smoothing=1.0, \ modelType="multinomial", thresholds=None, weightCol=None) Sets params for Naive Bayes. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return NaiveBayesModel(java_model)
[docs] @since("1.5.0") def setSmoothing(self, value): """ Sets the value of :py:attr:`smoothing`. """ return self._set(smoothing=value)
[docs] @since("1.5.0") def setModelType(self, value): """ Sets the value of :py:attr:`modelType`. """ return self._set(modelType=value)
[docs] def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs]class NaiveBayesModel(_JavaProbabilisticClassificationModel, _NaiveBayesParams, JavaMLWritable, JavaMLReadable): """ Model fitted by NaiveBayes. .. versionadded:: 1.5.0 """ @property @since("2.0.0") def pi(self): """ log of class priors. """ return self._call_java("pi") @property @since("2.0.0") def theta(self): """ log of class conditional probabilities. """ return self._call_java("theta") @property @since("3.0.0") def sigma(self): """ variance of each feature. """ return self._call_java("sigma")
class _MultilayerPerceptronParams(_ProbabilisticClassifierParams, HasSeed, HasMaxIter, HasTol, HasStepSize, HasSolver, HasBlockSize): """ Params for :py:class:`MultilayerPerceptronClassifier`. .. versionadded:: 3.0.0 """ layers = Param(Params._dummy(), "layers", "Sizes of layers from input layer to output layer " + "E.g., Array(780, 100, 10) means 780 inputs, one hidden layer with 100 " + "neurons and output layer of 10 neurons.", typeConverter=TypeConverters.toListInt) solver = Param(Params._dummy(), "solver", "The solver algorithm for optimization. Supported " + "options: l-bfgs, gd.", typeConverter=TypeConverters.toString) initialWeights = Param(Params._dummy(), "initialWeights", "The initial weights of the model.", typeConverter=TypeConverters.toVector) def __init__(self, *args): super(_MultilayerPerceptronParams, self).__init__(*args) self._setDefault(maxIter=100, tol=1E-6, blockSize=128, stepSize=0.03, solver="l-bfgs") @since("1.6.0") def getLayers(self): """ Gets the value of layers or its default value. """ return self.getOrDefault(self.layers) @since("2.0.0") def getInitialWeights(self): """ Gets the value of initialWeights or its default value. """ return self.getOrDefault(self.initialWeights)
[docs]@inherit_doc class MultilayerPerceptronClassifier(_JavaProbabilisticClassifier, _MultilayerPerceptronParams, JavaMLWritable, JavaMLReadable): """ Classifier trainer based on the Multilayer Perceptron. Each layer has sigmoid activation function, output layer has softmax. Number of inputs has to be equal to the size of feature vectors. Number of outputs has to be equal to the total number of labels. .. versionadded:: 1.6.0 Examples -------- >>> from pyspark.ml.linalg import Vectors >>> df = spark.createDataFrame([ ... (0.0, Vectors.dense([0.0, 0.0])), ... (1.0, Vectors.dense([0.0, 1.0])), ... (1.0, Vectors.dense([1.0, 0.0])), ... (0.0, Vectors.dense([1.0, 1.0]))], ["label", "features"]) >>> mlp = MultilayerPerceptronClassifier(layers=[2, 2, 2], seed=123) >>> mlp.setMaxIter(100) MultilayerPerceptronClassifier... >>> mlp.getMaxIter() 100 >>> mlp.getBlockSize() 128 >>> mlp.setBlockSize(1) MultilayerPerceptronClassifier... >>> mlp.getBlockSize() 1 >>> model = mlp.fit(df) >>> model.setFeaturesCol("features") MultilayerPerceptronClassificationModel... >>> model.getMaxIter() 100 >>> model.getLayers() [2, 2, 2] >>> model.weights.size 12 >>> testDF = spark.createDataFrame([ ... (Vectors.dense([1.0, 0.0]),), ... (Vectors.dense([0.0, 0.0]),)], ["features"]) >>> model.predict(testDF.head().features) 1.0 >>> model.predictRaw(testDF.head().features) DenseVector([-16.208, 16.344]) >>> model.predictProbability(testDF.head().features) DenseVector([0.0, 1.0]) >>> model.transform(testDF).select("features", "prediction").show() +---------+----------+ | features|prediction| +---------+----------+ |[1.0,0.0]| 1.0| |[0.0,0.0]| 0.0| +---------+----------+ ... >>> mlp_path = temp_path + "/mlp" >>> mlp.save(mlp_path) >>> mlp2 = MultilayerPerceptronClassifier.load(mlp_path) >>> mlp2.getBlockSize() 1 >>> model_path = temp_path + "/mlp_model" >>> model.save(model_path) >>> model2 = MultilayerPerceptronClassificationModel.load(model_path) >>> model.getLayers() == model2.getLayers() True >>> model.weights == model2.weights True >>> model.transform(testDF).take(1) == model2.transform(testDF).take(1) True >>> mlp2 = mlp2.setInitialWeights(list(range(0, 12))) >>> model3 = mlp2.fit(df) >>> model3.weights != model2.weights True >>> model3.getLayers() == model.getLayers() True """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxIter=100, tol=1e-6, seed=None, layers=None, blockSize=128, stepSize=0.03, solver="l-bfgs", initialWeights=None, probabilityCol="probability", rawPredictionCol="rawPrediction"): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxIter=100, tol=1e-6, seed=None, layers=None, blockSize=128, stepSize=0.03, \ solver="l-bfgs", initialWeights=None, probabilityCol="probability", \ rawPredictionCol="rawPrediction") """ super(MultilayerPerceptronClassifier, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.MultilayerPerceptronClassifier", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("1.6.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", maxIter=100, tol=1e-6, seed=None, layers=None, blockSize=128, stepSize=0.03, solver="l-bfgs", initialWeights=None, probabilityCol="probability", rawPredictionCol="rawPrediction"): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ maxIter=100, tol=1e-6, seed=None, layers=None, blockSize=128, stepSize=0.03, \ solver="l-bfgs", initialWeights=None, probabilityCol="probability", \ rawPredictionCol="rawPrediction"): Sets params for MultilayerPerceptronClassifier. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return MultilayerPerceptronClassificationModel(java_model)
[docs] @since("1.6.0") def setLayers(self, value): """ Sets the value of :py:attr:`layers`. """ return self._set(layers=value)
[docs] @since("1.6.0") def setBlockSize(self, value): """ Sets the value of :py:attr:`blockSize`. """ return self._set(blockSize=value)
[docs] @since("2.0.0") def setInitialWeights(self, value): """ Sets the value of :py:attr:`initialWeights`. """ return self._set(initialWeights=value)
[docs] def setMaxIter(self, value): """ Sets the value of :py:attr:`maxIter`. """ return self._set(maxIter=value)
[docs] def setSeed(self, value): """ Sets the value of :py:attr:`seed`. """ return self._set(seed=value)
[docs] def setTol(self, value): """ Sets the value of :py:attr:`tol`. """ return self._set(tol=value)
[docs] @since("2.0.0") def setStepSize(self, value): """ Sets the value of :py:attr:`stepSize`. """ return self._set(stepSize=value)
[docs] def setSolver(self, value): """ Sets the value of :py:attr:`solver`. """ return self._set(solver=value)
[docs]class MultilayerPerceptronClassificationModel(_JavaProbabilisticClassificationModel, _MultilayerPerceptronParams, JavaMLWritable, JavaMLReadable, HasTrainingSummary): """ Model fitted by MultilayerPerceptronClassifier. .. versionadded:: 1.6.0 """ @property @since("2.0.0") def weights(self): """ the weights of layers. """ return self._call_java("weights")
[docs] @since("3.1.0") def summary(self): """ Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model trained on the training set. An exception is thrown if `trainingSummary is None`. """ if self.hasSummary: return MultilayerPerceptronClassificationTrainingSummary( super(MultilayerPerceptronClassificationModel, self).summary) else: raise RuntimeError("No training summary available for this %s" % self.__class__.__name__)
[docs] def evaluate(self, dataset): """ Evaluates the model on a test dataset. .. versionadded:: 3.1.0 Parameters ---------- dataset : :py:class:`pyspark.sql.DataFrame` Test dataset to evaluate model on. """ if not isinstance(dataset, DataFrame): raise ValueError("dataset must be a DataFrame but got %s." % type(dataset)) java_mlp_summary = self._call_java("evaluate", dataset) return MultilayerPerceptronClassificationSummary(java_mlp_summary)
[docs]class MultilayerPerceptronClassificationSummary(_ClassificationSummary): """ Abstraction for MultilayerPerceptronClassifier Results for a given model. .. versionadded:: 3.1.0 """ pass
[docs]@inherit_doc class MultilayerPerceptronClassificationTrainingSummary(MultilayerPerceptronClassificationSummary, _TrainingSummary): """ Abstraction for MultilayerPerceptronClassifier Training results. .. versionadded:: 3.1.0 """ pass
class _OneVsRestParams(_ClassifierParams, HasWeightCol): """ Params for :py:class:`OneVsRest` and :py:class:`OneVsRestModelModel`. """ classifier = Param(Params._dummy(), "classifier", "base binary classifier") @since("2.0.0") def getClassifier(self): """ Gets the value of classifier or its default value. """ return self.getOrDefault(self.classifier)
[docs]@inherit_doc class OneVsRest(Estimator, _OneVsRestParams, HasParallelism, MLReadable, MLWritable): """ Reduction of Multiclass Classification to Binary Classification. Performs reduction using one against all strategy. For a multiclass classification with k classes, train k models (one per class). Each example is scored against all k models and the model with highest score is picked to label the example. .. versionadded:: 2.0.0 Examples -------- >>> from pyspark.sql import Row >>> from pyspark.ml.linalg import Vectors >>> data_path = "data/mllib/sample_multiclass_classification_data.txt" >>> df = spark.read.format("libsvm").load(data_path) >>> lr = LogisticRegression(regParam=0.01) >>> ovr = OneVsRest(classifier=lr) >>> ovr.getRawPredictionCol() 'rawPrediction' >>> ovr.setPredictionCol("newPrediction") OneVsRest... >>> model = ovr.fit(df) >>> model.models[0].coefficients DenseVector([0.5..., -1.0..., 3.4..., 4.2...]) >>> model.models[1].coefficients DenseVector([-2.1..., 3.1..., -2.6..., -2.3...]) >>> model.models[2].coefficients DenseVector([0.3..., -3.4..., 1.0..., -1.1...]) >>> [x.intercept for x in model.models] [-2.7..., -2.5..., -1.3...] >>> test0 = sc.parallelize([Row(features=Vectors.dense(-1.0, 0.0, 1.0, 1.0))]).toDF() >>> model.transform(test0).head().newPrediction 0.0 >>> test1 = sc.parallelize([Row(features=Vectors.sparse(4, [0], [1.0]))]).toDF() >>> model.transform(test1).head().newPrediction 2.0 >>> test2 = sc.parallelize([Row(features=Vectors.dense(0.5, 0.4, 0.3, 0.2))]).toDF() >>> model.transform(test2).head().newPrediction 0.0 >>> model_path = temp_path + "/ovr_model" >>> model.save(model_path) >>> model2 = OneVsRestModel.load(model_path) >>> model2.transform(test0).head().newPrediction 0.0 >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True >>> model.transform(test2).columns ['features', 'rawPrediction', 'newPrediction'] """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", rawPredictionCol="rawPrediction", classifier=None, weightCol=None, parallelism=1): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ rawPredictionCol="rawPrediction", classifier=None, weightCol=None, parallelism=1): """ super(OneVsRest, self).__init__() self._setDefault(parallelism=1) kwargs = self._input_kwargs self._set(**kwargs)
[docs] @keyword_only @since("2.0.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", rawPredictionCol="rawPrediction", classifier=None, weightCol=None, parallelism=1): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ rawPredictionCol="rawPrediction", classifier=None, weightCol=None, parallelism=1): Sets params for OneVsRest. """ kwargs = self._input_kwargs return self._set(**kwargs)
[docs] @since("2.0.0") def setClassifier(self, value): """ Sets the value of :py:attr:`classifier`. """ return self._set(classifier=value)
[docs] def setLabelCol(self, value): """ Sets the value of :py:attr:`labelCol`. """ return self._set(labelCol=value)
[docs] def setFeaturesCol(self, value): """ Sets the value of :py:attr:`featuresCol`. """ return self._set(featuresCol=value)
[docs] def setPredictionCol(self, value): """ Sets the value of :py:attr:`predictionCol`. """ return self._set(predictionCol=value)
[docs] def setRawPredictionCol(self, value): """ Sets the value of :py:attr:`rawPredictionCol`. """ return self._set(rawPredictionCol=value)
[docs] def setWeightCol(self, value): """ Sets the value of :py:attr:`weightCol`. """ return self._set(weightCol=value)
[docs] def setParallelism(self, value): """ Sets the value of :py:attr:`parallelism`. """ return self._set(parallelism=value)
def _fit(self, dataset): labelCol = self.getLabelCol() featuresCol = self.getFeaturesCol() predictionCol = self.getPredictionCol() classifier = self.getClassifier() numClasses = int(dataset.agg({labelCol: "max"}).head()["max("+labelCol+")"]) + 1 weightCol = None if (self.isDefined(self.weightCol) and self.getWeightCol()): if isinstance(classifier, HasWeightCol): weightCol = self.getWeightCol() else: warnings.warn("weightCol is ignored, " "as it is not supported by {} now.".format(classifier)) if weightCol: multiclassLabeled = dataset.select(labelCol, featuresCol, weightCol) else: multiclassLabeled = dataset.select(labelCol, featuresCol) # persist if underlying dataset is not persistent. handlePersistence = dataset.storageLevel == StorageLevel(False, False, False, False) if handlePersistence: multiclassLabeled.persist(StorageLevel.MEMORY_AND_DISK) def trainSingleClass(index): binaryLabelCol = "mc2b$" + str(index) trainingDataset = multiclassLabeled.withColumn( binaryLabelCol, when(multiclassLabeled[labelCol] == float(index), 1.0).otherwise(0.0)) paramMap = dict([(classifier.labelCol, binaryLabelCol), (classifier.featuresCol, featuresCol), (classifier.predictionCol, predictionCol)]) if weightCol: paramMap[classifier.weightCol] = weightCol return classifier.fit(trainingDataset, paramMap) pool = ThreadPool(processes=min(self.getParallelism(), numClasses)) models = pool.map(trainSingleClass, range(numClasses)) if handlePersistence: multiclassLabeled.unpersist() return self._copyValues(OneVsRestModel(models=models))
[docs] def copy(self, extra=None): """ Creates a copy of this instance with a randomly generated uid and some extra params. This creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. .. versionadded:: 2.0.0 Examples -------- extra : dict, optional Extra parameters to copy to the new instance Returns ------- :py:class:`OneVsRest` Copy of this instance """ if extra is None: extra = dict() newOvr = Params.copy(self, extra) if self.isSet(self.classifier): newOvr.setClassifier(self.getClassifier().copy(extra)) return newOvr
@classmethod def _from_java(cls, java_stage): """ Given a Java OneVsRest, create and return a Python wrapper of it. Used for ML persistence. """ featuresCol = java_stage.getFeaturesCol() labelCol = java_stage.getLabelCol() predictionCol = java_stage.getPredictionCol() rawPredictionCol = java_stage.getRawPredictionCol() classifier = JavaParams._from_java(java_stage.getClassifier()) parallelism = java_stage.getParallelism() py_stage = cls(featuresCol=featuresCol, labelCol=labelCol, predictionCol=predictionCol, rawPredictionCol=rawPredictionCol, classifier=classifier, parallelism=parallelism) if java_stage.isDefined(java_stage.getParam("weightCol")): py_stage.setWeightCol(java_stage.getWeightCol()) py_stage._resetUid(java_stage.uid()) return py_stage def _to_java(self): """ Transfer this instance to a Java OneVsRest. Used for ML persistence. Returns ------- py4j.java_gateway.JavaObject Java object equivalent to this instance. """ _java_obj = JavaParams._new_java_obj("org.apache.spark.ml.classification.OneVsRest", self.uid) _java_obj.setClassifier(self.getClassifier()._to_java()) _java_obj.setParallelism(self.getParallelism()) _java_obj.setFeaturesCol(self.getFeaturesCol()) _java_obj.setLabelCol(self.getLabelCol()) _java_obj.setPredictionCol(self.getPredictionCol()) if (self.isDefined(self.weightCol) and self.getWeightCol()): _java_obj.setWeightCol(self.getWeightCol()) _java_obj.setRawPredictionCol(self.getRawPredictionCol()) return _java_obj
[docs] @classmethod def read(cls): return OneVsRestReader(cls)
[docs] def write(self): if isinstance(self.getClassifier(), JavaMLWritable): return JavaMLWriter(self) else: return OneVsRestWriter(self)
class _OneVsRestSharedReadWrite: @staticmethod def saveImpl(instance, sc, path, extraMetadata=None): skipParams = ['classifier'] jsonParams = DefaultParamsWriter.extractJsonParams(instance, skipParams) DefaultParamsWriter.saveMetadata(instance, path, sc, paramMap=jsonParams, extraMetadata=extraMetadata) classifierPath = os.path.join(path, 'classifier') instance.getClassifier().save(classifierPath) @staticmethod def loadClassifier(path, sc): classifierPath = os.path.join(path, 'classifier') return DefaultParamsReader.loadParamsInstance(classifierPath, sc) @staticmethod def validateParams(instance): elems_to_check = [instance.getClassifier()] if isinstance(instance, OneVsRestModel): elems_to_check.extend(instance.models) for elem in elems_to_check: if not isinstance(elem, MLWritable): raise ValueError(f'OneVsRest write will fail because it contains {elem.uid} ' f'which is not writable.') @inherit_doc class OneVsRestReader(MLReader): def __init__(self, cls): super(OneVsRestReader, self).__init__() self.cls = cls def load(self, path): metadata = DefaultParamsReader.loadMetadata(path, self.sc) if not DefaultParamsReader.isPythonParamsInstance(metadata): return JavaMLReader(self.cls).load(path) else: classifier = _OneVsRestSharedReadWrite.loadClassifier(path, self.sc) ova = OneVsRest(classifier=classifier)._resetUid(metadata['uid']) DefaultParamsReader.getAndSetParams(ova, metadata, skipParams=['classifier']) return ova @inherit_doc class OneVsRestWriter(MLWriter): def __init__(self, instance): super(OneVsRestWriter, self).__init__() self.instance = instance def saveImpl(self, path): _OneVsRestSharedReadWrite.validateParams(self.instance) _OneVsRestSharedReadWrite.saveImpl(self.instance, self.sc, path)
[docs]class OneVsRestModel(Model, _OneVsRestParams, MLReadable, MLWritable): """ Model fitted by OneVsRest. This stores the models resulting from training k binary classifiers: one for each class. Each example is scored against all k models, and the model with the highest score is picked to label the example. .. versionadded:: 2.0.0 """
[docs] def setFeaturesCol(self, value): """ Sets the value of :py:attr:`featuresCol`. """ return self._set(featuresCol=value)
[docs] def setPredictionCol(self, value): """ Sets the value of :py:attr:`predictionCol`. """ return self._set(predictionCol=value)
[docs] def setRawPredictionCol(self, value): """ Sets the value of :py:attr:`rawPredictionCol`. """ return self._set(rawPredictionCol=value)
def __init__(self, models): super(OneVsRestModel, self).__init__() self.models = models if not isinstance(models[0], JavaMLWritable): return # set java instance java_models = [model._to_java() for model in self.models] sc = SparkContext._active_spark_context java_models_array = JavaWrapper._new_java_array(java_models, sc._gateway.jvm.org.apache.spark.ml .classification.ClassificationModel) # TODO: need to set metadata metadata = JavaParams._new_java_obj("org.apache.spark.sql.types.Metadata") self._java_obj = \ JavaParams._new_java_obj("org.apache.spark.ml.classification.OneVsRestModel", self.uid, metadata.empty(), java_models_array) def _transform(self, dataset): # determine the input columns: these need to be passed through origCols = dataset.columns # add an accumulator column to store predictions of all the models accColName = "mbc$acc" + str(uuid.uuid4()) initUDF = udf(lambda _: [], ArrayType(DoubleType())) newDataset = dataset.withColumn(accColName, initUDF(dataset[origCols[0]])) # persist if underlying dataset is not persistent. handlePersistence = dataset.storageLevel == StorageLevel(False, False, False, False) if handlePersistence: newDataset.persist(StorageLevel.MEMORY_AND_DISK) # update the accumulator column with the result of prediction of models aggregatedDataset = newDataset for index, model in enumerate(self.models): rawPredictionCol = self.getRawPredictionCol() columns = origCols + [rawPredictionCol, accColName] # add temporary column to store intermediate scores and update tmpColName = "mbc$tmp" + str(uuid.uuid4()) updateUDF = udf( lambda predictions, prediction: predictions + [prediction.tolist()[1]], ArrayType(DoubleType())) transformedDataset = model.transform(aggregatedDataset).select(*columns) updatedDataset = transformedDataset.withColumn( tmpColName, updateUDF(transformedDataset[accColName], transformedDataset[rawPredictionCol])) newColumns = origCols + [tmpColName] # switch out the intermediate column with the accumulator column aggregatedDataset = updatedDataset\ .select(*newColumns).withColumnRenamed(tmpColName, accColName) if handlePersistence: newDataset.unpersist() if self.getRawPredictionCol(): def func(predictions): predArray = [] for x in predictions: predArray.append(x) return Vectors.dense(predArray) rawPredictionUDF = udf(func) aggregatedDataset = aggregatedDataset.withColumn( self.getRawPredictionCol(), rawPredictionUDF(aggregatedDataset[accColName])) if self.getPredictionCol(): # output the index of the classifier with highest confidence as prediction labelUDF = udf(lambda predictions: float(max(enumerate(predictions), key=operator.itemgetter(1))[0]), DoubleType()) aggregatedDataset = aggregatedDataset.withColumn( self.getPredictionCol(), labelUDF(aggregatedDataset[accColName])) return aggregatedDataset.drop(accColName)
[docs] def copy(self, extra=None): """ Creates a copy of this instance with a randomly generated uid and some extra params. This creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. .. versionadded:: 2.0.0 Parameters ---------- extra : dict, optional Extra parameters to copy to the new instance Returns ------- :py:class:`OneVsRestModel` Copy of this instance """ if extra is None: extra = dict() newModel = Params.copy(self, extra) newModel.models = [model.copy(extra) for model in self.models] return newModel
@classmethod def _from_java(cls, java_stage): """ Given a Java OneVsRestModel, create and return a Python wrapper of it. Used for ML persistence. """ featuresCol = java_stage.getFeaturesCol() labelCol = java_stage.getLabelCol() predictionCol = java_stage.getPredictionCol() classifier = JavaParams._from_java(java_stage.getClassifier()) models = [JavaParams._from_java(model) for model in java_stage.models()] py_stage = cls(models=models).setPredictionCol(predictionCol)\ .setFeaturesCol(featuresCol) py_stage._set(labelCol=labelCol) if java_stage.isDefined(java_stage.getParam("weightCol")): py_stage._set(weightCol=java_stage.getWeightCol()) py_stage._set(classifier=classifier) py_stage._resetUid(java_stage.uid()) return py_stage def _to_java(self): """ Transfer this instance to a Java OneVsRestModel. Used for ML persistence. Returns ------- py4j.java_gateway.JavaObject Java object equivalent to this instance. """ sc = SparkContext._active_spark_context java_models = [model._to_java() for model in self.models] java_models_array = JavaWrapper._new_java_array( java_models, sc._gateway.jvm.org.apache.spark.ml.classification.ClassificationModel) metadata = JavaParams._new_java_obj("org.apache.spark.sql.types.Metadata") _java_obj = JavaParams._new_java_obj("org.apache.spark.ml.classification.OneVsRestModel", self.uid, metadata.empty(), java_models_array) _java_obj.set("classifier", self.getClassifier()._to_java()) _java_obj.set("featuresCol", self.getFeaturesCol()) _java_obj.set("labelCol", self.getLabelCol()) _java_obj.set("predictionCol", self.getPredictionCol()) if (self.isDefined(self.weightCol) and self.getWeightCol()): _java_obj.set("weightCol", self.getWeightCol()) return _java_obj
[docs] @classmethod def read(cls): return OneVsRestModelReader(cls)
[docs] def write(self): if all(map(lambda elem: isinstance(elem, JavaMLWritable), [self.getClassifier()] + self.models)): return JavaMLWriter(self) else: return OneVsRestModelWriter(self)
@inherit_doc class OneVsRestModelReader(MLReader): def __init__(self, cls): super(OneVsRestModelReader, self).__init__() self.cls = cls def load(self, path): metadata = DefaultParamsReader.loadMetadata(path, self.sc) if not DefaultParamsReader.isPythonParamsInstance(metadata): return JavaMLReader(self.cls).load(path) else: classifier = _OneVsRestSharedReadWrite.loadClassifier(path, self.sc) numClasses = metadata['numClasses'] subModels = [None] * numClasses for idx in range(numClasses): subModelPath = os.path.join(path, f'model_{idx}') subModels[idx] = DefaultParamsReader.loadParamsInstance(subModelPath, self.sc) ovaModel = OneVsRestModel(subModels)._resetUid(metadata['uid']) ovaModel.set(ovaModel.classifier, classifier) DefaultParamsReader.getAndSetParams(ovaModel, metadata, skipParams=['classifier']) return ovaModel @inherit_doc class OneVsRestModelWriter(MLWriter): def __init__(self, instance): super(OneVsRestModelWriter, self).__init__() self.instance = instance def saveImpl(self, path): _OneVsRestSharedReadWrite.validateParams(self.instance) instance = self.instance numClasses = len(instance.models) extraMetadata = {'numClasses': numClasses} _OneVsRestSharedReadWrite.saveImpl(instance, self.sc, path, extraMetadata=extraMetadata) for idx in range(numClasses): subModelPath = os.path.join(path, f'model_{idx}') instance.models[idx].save(subModelPath)
[docs]@inherit_doc class FMClassifier(_JavaProbabilisticClassifier, _FactorizationMachinesParams, JavaMLWritable, JavaMLReadable): """ Factorization Machines learning algorithm for classification. Solver supports: * gd (normal mini-batch gradient descent) * adamW (default) .. versionadded:: 3.0.0 Examples -------- >>> from pyspark.ml.linalg import Vectors >>> from pyspark.ml.classification import FMClassifier >>> df = spark.createDataFrame([ ... (1.0, Vectors.dense(1.0)), ... (0.0, Vectors.sparse(1, [], []))], ["label", "features"]) >>> fm = FMClassifier(factorSize=2) >>> fm.setSeed(11) FMClassifier... >>> model = fm.fit(df) >>> model.getMaxIter() 100 >>> test0 = spark.createDataFrame([ ... (Vectors.dense(-1.0),), ... (Vectors.dense(0.5),), ... (Vectors.dense(1.0),), ... (Vectors.dense(2.0),)], ["features"]) >>> model.predictRaw(test0.head().features) DenseVector([22.13..., -22.13...]) >>> model.predictProbability(test0.head().features) DenseVector([1.0, 0.0]) >>> model.transform(test0).select("features", "probability").show(10, False) +--------+------------------------------------------+ |features|probability | +--------+------------------------------------------+ |[-1.0] |[0.9999999997574736,2.425264676902229E-10]| |[0.5] |[0.47627851732981163,0.5237214826701884] | |[1.0] |[5.491554426243495E-4,0.9994508445573757] | |[2.0] |[2.005766663870645E-10,0.9999999997994233]| +--------+------------------------------------------+ ... >>> model.intercept -7.316665276826291 >>> model.linear DenseVector([14.8232]) >>> model.factors DenseMatrix(1, 2, [0.0163, -0.0051], 1) >>> model_path = temp_path + "/fm_model" >>> model.save(model_path) >>> model2 = FMClassificationModel.load(model_path) >>> model2.intercept -7.316665276826291 >>> model2.linear DenseVector([14.8232]) >>> model2.factors DenseMatrix(1, 2, [0.0163, -0.0051], 1) >>> model.transform(test0).take(1) == model2.transform(test0).take(1) True """ @keyword_only def __init__(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", factorSize=8, fitIntercept=True, fitLinear=True, regParam=0.0, miniBatchFraction=1.0, initStd=0.01, maxIter=100, stepSize=1.0, tol=1e-6, solver="adamW", thresholds=None, seed=None): """ __init__(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", \ factorSize=8, fitIntercept=True, fitLinear=True, regParam=0.0, \ miniBatchFraction=1.0, initStd=0.01, maxIter=100, stepSize=1.0, \ tol=1e-6, solver="adamW", thresholds=None, seed=None) """ super(FMClassifier, self).__init__() self._java_obj = self._new_java_obj( "org.apache.spark.ml.classification.FMClassifier", self.uid) kwargs = self._input_kwargs self.setParams(**kwargs)
[docs] @keyword_only @since("3.0.0") def setParams(self, *, featuresCol="features", labelCol="label", predictionCol="prediction", probabilityCol="probability", rawPredictionCol="rawPrediction", factorSize=8, fitIntercept=True, fitLinear=True, regParam=0.0, miniBatchFraction=1.0, initStd=0.01, maxIter=100, stepSize=1.0, tol=1e-6, solver="adamW", thresholds=None, seed=None): """ setParams(self, \\*, featuresCol="features", labelCol="label", predictionCol="prediction", \ probabilityCol="probability", rawPredictionCol="rawPrediction", \ factorSize=8, fitIntercept=True, fitLinear=True, regParam=0.0, \ miniBatchFraction=1.0, initStd=0.01, maxIter=100, stepSize=1.0, \ tol=1e-6, solver="adamW", thresholds=None, seed=None) Sets Params for FMClassifier. """ kwargs = self._input_kwargs return self._set(**kwargs)
def _create_model(self, java_model): return FMClassificationModel(java_model)
[docs] @since("3.0.0") def setFactorSize(self, value): """ Sets the value of :py:attr:`factorSize`. """ return self._set(factorSize=value)
[docs] @since("3.0.0") def setFitLinear(self, value): """ Sets the value of :py:attr:`fitLinear`. """ return self._set(fitLinear=value)
[docs] @since("3.0.0") def setMiniBatchFraction(self, value): """ Sets the value of :py:attr:`miniBatchFraction`. """ return self._set(miniBatchFraction=value)
[docs] @since("3.0.0") def setInitStd(self, value): """ Sets the value of :py:attr:`initStd`. """ return self._set(initStd=value)
[docs] @since("3.0.0") def setMaxIter(self, value): """ Sets the value of :py:attr:`maxIter`. """ return self._set(maxIter=value)
[docs] @since("3.0.0") def setStepSize(self, value): """ Sets the value of :py:attr:`stepSize`. """ return self._set(stepSize=value)
[docs] @since("3.0.0") def setTol(self, value): """ Sets the value of :py:attr:`tol`. """ return self._set(tol=value)
[docs] @since("3.0.0") def setSolver(self, value): """ Sets the value of :py:attr:`solver`. """ return self._set(solver=value)
[docs] @since("3.0.0") def setSeed(self, value): """ Sets the value of :py:attr:`seed`. """ return self._set(seed=value)
[docs] @since("3.0.0") def setFitIntercept(self, value): """ Sets the value of :py:attr:`fitIntercept`. """ return self._set(fitIntercept=value)
[docs] @since("3.0.0") def setRegParam(self, value): """ Sets the value of :py:attr:`regParam`. """ return self._set(regParam=value)
[docs]class FMClassificationModel(_JavaProbabilisticClassificationModel, _FactorizationMachinesParams, JavaMLWritable, JavaMLReadable, HasTrainingSummary): """ Model fitted by :class:`FMClassifier`. .. versionadded:: 3.0.0 """ @property @since("3.0.0") def intercept(self): """ Model intercept. """ return self._call_java("intercept") @property @since("3.0.0") def linear(self): """ Model linear term. """ return self._call_java("linear") @property @since("3.0.0") def factors(self): """ Model factor term. """ return self._call_java("factors")
[docs] @since("3.1.0") def summary(self): """ Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model trained on the training set. An exception is thrown if `trainingSummary is None`. """ if self.hasSummary: return FMClassificationTrainingSummary(super(FMClassificationModel, self).summary) else: raise RuntimeError("No training summary available for this %s" % self.__class__.__name__)
[docs] def evaluate(self, dataset): """ Evaluates the model on a test dataset. .. versionadded:: 3.1.0 Parameters ---------- dataset : :py:class:`pyspark.sql.DataFrame` Test dataset to evaluate model on. """ if not isinstance(dataset, DataFrame): raise ValueError("dataset must be a DataFrame but got %s." % type(dataset)) java_fm_summary = self._call_java("evaluate", dataset) return FMClassificationSummary(java_fm_summary)
[docs]class FMClassificationSummary(_BinaryClassificationSummary): """ Abstraction for FMClassifier Results for a given model. .. versionadded:: 3.1.0 """ pass
[docs]@inherit_doc class FMClassificationTrainingSummary(FMClassificationSummary, _TrainingSummary): """ Abstraction for FMClassifier Training results. .. versionadded:: 3.1.0 """ pass
if __name__ == "__main__": import doctest import pyspark.ml.classification from pyspark.sql import SparkSession globs = pyspark.ml.classification.__dict__.copy() # The small batch size here ensures that we see multiple batches, # even in these small test examples: spark = SparkSession.builder\ .master("local[2]")\ .appName("ml.classification tests")\ .getOrCreate() sc = spark.sparkContext globs['sc'] = sc globs['spark'] = spark import tempfile temp_path = tempfile.mkdtemp() globs['temp_path'] = temp_path try: (failure_count, test_count) = doctest.testmod(globs=globs, optionflags=doctest.ELLIPSIS) spark.stop() finally: from shutil import rmtree try: rmtree(temp_path) except OSError: pass if failure_count: sys.exit(-1)