Packages

Definition Classes: root

Definition Classes: root

Definition Classes: org

Core Spark functionality.

Core Spark functionality. org.apache.spark.SparkContext serves as the main entry point to Spark, while org.apache.spark.rdd.RDD is the data type representing a distributed collection, and provides most parallel operations.

In addition, org.apache.spark.rdd.PairRDDFunctions contains operations available only on RDDs of key-value pairs, such as groupByKey and join; org.apache.spark.rdd.DoubleRDDFunctions contains operations available only on RDDs of Doubles; and org.apache.spark.rdd.SequenceFileRDDFunctions contains operations available on RDDs that can be saved as SequenceFiles. These operations are automatically available on any RDD of the right type (e.g. RDD[(Int, Int)] through implicit conversions.

Java programmers should reference the org.apache.spark.api.java package for Spark programming APIs in Java.

Classes and methods marked with Experimental are user-facing features which have not been officially adopted by the Spark project. These are subject to change or removal in minor releases.

Classes and methods marked with Developer API are intended for advanced users want to extend Spark through lower level interfaces. These are subject to changes or removal in minor releases.

Definition Classes: apache

package api

Definition Classes: spark

package broadcast

Spark's broadcast variables, used to broadcast immutable datasets to all nodes.

Definition Classes: spark

package graphx

ALPHA COMPONENT GraphX is a graph processing framework built on top of Spark.

Definition Classes: spark

package input

Definition Classes: spark

package io

IO codecs used for compression.

IO codecs used for compression. See org.apache.spark.io.CompressionCodec.

Definition Classes: spark

package launcher

Definition Classes: spark

package mapred

Definition Classes: spark

package metrics

Definition Classes: spark

package ml

DataFrame-based machine learning APIs to let users quickly assemble and configure practical machine learning pipelines.

Definition Classes: spark

package attribute

The ML pipeline API uses DataFrames as ML datasets.

ML attributes

The ML pipeline API uses DataFrames as ML datasets. Each dataset consists of typed columns, e.g., string, double, vector, etc. However, knowing only the column type may not be sufficient to handle the data properly. For instance, a double column with values 0.0, 1.0, 2.0, ... may represent some label indices, which cannot be treated as numeric values in ML algorithms, and, for another instance, we may want to know the names and types of features stored in a vector column. ML attributes are used to provide additional information to describe columns in a dataset.

ML columns

A column with ML attributes attached is called an ML column. The data in ML columns are stored as double values, i.e., an ML column is either a scalar column of double values or a vector column. Columns of other types must be encoded into ML columns using transformers. We use Attribute to describe a scalar ML column, and AttributeGroup to describe a vector ML column. ML attributes are stored in the metadata field of the column schema.

package classification

package clustering

package evaluation

package feature

The ml.feature package provides common feature transformers that help convert raw data or features into more suitable forms for model fitting.

Feature transformers

The ml.feature package provides common feature transformers that help convert raw data or features into more suitable forms for model fitting. Most feature transformers are implemented as Transformers, which transform one DataFrame into another, e.g., HashingTF. Some feature transformers are implemented as Estimators, because the transformation requires some aggregated information of the dataset, e.g., document frequencies in IDF. For those feature transformers, calling Estimator.fit is required to obtain the model first, e.g., IDFModel, in order to apply transformation. The transformation is usually done by appending new columns to the input DataFrame, so all input columns are carried over.

We try to make each transformer minimal, so it becomes flexible to assemble feature transformation pipelines. Pipeline can be used to chain feature transformers, and VectorAssembler can be used to combine multiple feature transformations, for example:

import org.apache.spark.ml.feature._
import org.apache.spark.ml.Pipeline

// a DataFrame with three columns: id (integer), text (string), and rating (double).
val df = spark.createDataFrame(Seq(
  (0, "Hi I heard about Spark", 3.0),
  (1, "I wish Java could use case classes", 4.0),
  (2, "Logistic regression models are neat", 4.0)
)).toDF("id", "text", "rating")

// define feature transformers
val tok = new RegexTokenizer()
  .setInputCol("text")
  .setOutputCol("words")
val sw = new StopWordsRemover()
  .setInputCol("words")
  .setOutputCol("filtered_words")
val tf = new HashingTF()
  .setInputCol("filtered_words")
  .setOutputCol("tf")
  .setNumFeatures(10000)
val idf = new IDF()
  .setInputCol("tf")
  .setOutputCol("tf_idf")
val assembler = new VectorAssembler()
  .setInputCols(Array("tf_idf", "rating"))
  .setOutputCol("features")

// assemble and fit the feature transformation pipeline
val pipeline = new Pipeline()
  .setStages(Array(tok, sw, tf, idf, assembler))
val model = pipeline.fit(df)

// save transformed features with raw data
model.transform(df)
  .select("id", "text", "rating", "features")
  .write.format("parquet").save("/output/path")

Some feature transformers implemented in MLlib are inspired by those implemented in scikit-learn. The major difference is that most scikit-learn feature transformers operate eagerly on the entire input dataset, while MLlib's feature transformers operate lazily on individual columns, which is more efficient and flexible to handle large and complex datasets.

See also: scikit-learn.preprocessing

package fpm

package image

package linalg

package param

package recommendation

package regression

package source

package stat

package tree

package tuning

package util

package mllib

RDD-based machine learning APIs (in maintenance mode).

The spark.mllib package is in maintenance mode as of the Spark 2.0.0 release to encourage migration to the DataFrame-based APIs under the org.apache.spark.ml package. While in maintenance mode,

no new features in the RDD-based spark.mllib package will be accepted, unless they block implementing new features in the DataFrame-based spark.ml package;
bug fixes in the RDD-based APIs will still be accepted.

The developers will continue adding more features to the DataFrame-based APIs in the 2.x series to reach feature parity with the RDD-based APIs. And once we reach feature parity, this package will be deprecated.

Definition Classes: spark
See also: SPARK-4591 to track the progress of feature parity

package partial

Support for approximate results.

Support for approximate results. This provides convenient api and also implementation for approximate calculation.

Definition Classes: spark
See also: org.apache.spark.rdd.RDD.countApprox

package paths

Definition Classes: spark

package rdd

Provides several RDD implementations.

Provides several RDD implementations. See org.apache.spark.rdd.RDD.

Definition Classes: spark

package resource

Definition Classes: spark

package scheduler

Spark's scheduling components.

Spark's scheduling components. This includes the org.apache.spark.scheduler.DAGScheduler and lower level org.apache.spark.scheduler.TaskScheduler.

Definition Classes: spark

package security

Definition Classes: spark

package serializer

Pluggable serializers for RDD and shuffle data.

Definition Classes: spark
See also: org.apache.spark.serializer.Serializer

package shuffle

Definition Classes: spark

package sql

Allows the execution of relational queries, including those expressed in SQL using Spark.

Definition Classes: spark

package status

Definition Classes: spark

package storage

Definition Classes: spark

package streaming

Spark Streaming functionality.

Spark Streaming functionality. org.apache.spark.streaming.StreamingContext serves as the main entry point to Spark Streaming, while org.apache.spark.streaming.dstream.DStream is the data type representing a continuous sequence of RDDs, representing a continuous stream of data.

In addition, org.apache.spark.streaming.dstream.PairDStreamFunctions contains operations available only on DStreams of key-value pairs, such as groupByKey and reduceByKey. These operations are automatically available on any DStream of the right type (e.g. DStream[(Int, Int)] through implicit conversions.

For the Java API of Spark Streaming, take a look at the org.apache.spark.streaming.api.java.JavaStreamingContext which serves as the entry point, and the org.apache.spark.streaming.api.java.JavaDStream and the org.apache.spark.streaming.api.java.JavaPairDStream which have the DStream functionality.

Definition Classes: spark

package types

Definition Classes: spark

package ui

Definition Classes: spark

package unsafe

Definition Classes: spark

package util

Spark utilities.

Definition Classes: spark

org.apache.spark

ml

package ml

DataFrame-based machine learning APIs to let users quickly assemble and configure practical machine learning pipelines.

Source: package.scala

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package attribute
The ML pipeline API uses DataFrames as ML datasets.
ML attributes
The ML pipeline API uses DataFrames as ML datasets. Each dataset consists of typed columns, e.g., string, double, vector, etc. However, knowing only the column type may not be sufficient to handle the data properly. For instance, a double column with values 0.0, 1.0, 2.0, ... may represent some label indices, which cannot be treated as numeric values in ML algorithms, and, for another instance, we may want to know the names and types of features stored in a vector column. ML attributes are used to provide additional information to describe columns in a dataset.
ML columns
A column with ML attributes attached is called an ML column. The data in ML columns are stored as double values, i.e., an ML column is either a scalar column of double values or a vector column. Columns of other types must be encoded into ML columns using transformers. We use Attribute to describe a scalar ML column, and AttributeGroup to describe a vector ML column. ML attributes are stored in the metadata field of the column schema.
package classification
package clustering
package evaluation
package feature
The ml.feature package provides common feature transformers that help convert raw data or features into more suitable forms for model fitting.
Feature transformers
The ml.feature package provides common feature transformers that help convert raw data or features into more suitable forms for model fitting. Most feature transformers are implemented as Transformers, which transform one DataFrame into another, e.g., HashingTF. Some feature transformers are implemented as Estimators, because the transformation requires some aggregated information of the dataset, e.g., document frequencies in IDF. For those feature transformers, calling Estimator.fit is required to obtain the model first, e.g., IDFModel, in order to apply transformation. The transformation is usually done by appending new columns to the input DataFrame, so all input columns are carried over.
We try to make each transformer minimal, so it becomes flexible to assemble feature transformation pipelines. Pipeline can be used to chain feature transformers, and VectorAssembler can be used to combine multiple feature transformations, for example:
```
import org.apache.spark.ml.feature._
import org.apache.spark.ml.Pipeline

// a DataFrame with three columns: id (integer), text (string), and rating (double).
val df = spark.createDataFrame(Seq(
  (0, "Hi I heard about Spark", 3.0),
  (1, "I wish Java could use case classes", 4.0),
  (2, "Logistic regression models are neat", 4.0)
)).toDF("id", "text", "rating")

// define feature transformers
val tok = new RegexTokenizer()
  .setInputCol("text")
  .setOutputCol("words")
val sw = new StopWordsRemover()
  .setInputCol("words")
  .setOutputCol("filtered_words")
val tf = new HashingTF()
  .setInputCol("filtered_words")
  .setOutputCol("tf")
  .setNumFeatures(10000)
val idf = new IDF()
  .setInputCol("tf")
  .setOutputCol("tf_idf")
val assembler = new VectorAssembler()
  .setInputCols(Array("tf_idf", "rating"))
  .setOutputCol("features")

// assemble and fit the feature transformation pipeline
val pipeline = new Pipeline()
  .setStages(Array(tok, sw, tf, idf, assembler))
val model = pipeline.fit(df)

// save transformed features with raw data
model.transform(df)
  .select("id", "text", "rating", "features")
  .write.format("parquet").save("/output/path")
```
Some feature transformers implemented in MLlib are inspired by those implemented in scikit-learn. The major difference is that most scikit-learn feature transformers operate eagerly on the entire input dataset, while MLlib's feature transformers operate lazily on individual columns, which is more efficient and flexible to handle large and complex datasets.
See also
scikit-learn.preprocessing
package fpm
package image
package linalg
package param
package recommendation
package regression
package source
package stat
package tree
package tuning
package util

Type Members

abstract class Estimator[M <: Model[M]] extends PipelineStage
Abstract class for estimators that fit models to data.
case class FitEnd[M <: Model[M]]() extends MLEvent with Product with Serializable
Event fired after Estimator.fit.
Event fired after Estimator.fit.
Annotations
@Evolving()
case class FitStart[M <: Model[M]]() extends MLEvent with Product with Serializable
Event fired before Estimator.fit.
Event fired before Estimator.fit.
Annotations
@Evolving()
case class LoadInstanceEnd[T]() extends MLEvent with Product with Serializable
Event fired after MLReader.load.
Event fired after MLReader.load.
Annotations
@Evolving()
case class LoadInstanceStart[T](path: String) extends MLEvent with Product with Serializable
Event fired before MLReader.load.
Event fired before MLReader.load.
Annotations
@Evolving()
sealed trait MLEvent extends SparkListenerEvent
Event emitted by ML operations.
Event emitted by ML operations. Events are either fired before and/or after each operation (the event should document this).
Annotations
@Evolving()
Note
This is supported via Pipeline and PipelineModel.
abstract class Model[M <: Model[M]] extends Transformer
A fitted model, i.e., a Transformer produced by an Estimator.
A fitted model, i.e., a Transformer produced by an Estimator.
M
model type
class Pipeline extends Estimator[PipelineModel] with MLWritable
A simple pipeline, which acts as an estimator.
A simple pipeline, which acts as an estimator. A Pipeline consists of a sequence of stages, each of which is either an Estimator or a Transformer. When Pipeline.fit is called, the stages are executed in order. If a stage is an Estimator, its Estimator.fit method will be called on the input dataset to fit a model. Then the model, which is a transformer, will be used to transform the dataset as the input to the next stage. If a stage is a Transformer, its Transformer.transform method will be called to produce the dataset for the next stage. The fitted model from a Pipeline is a PipelineModel, which consists of fitted models and transformers, corresponding to the pipeline stages. If there are no stages, the pipeline acts as an identity transformer.
Annotations
@Since("1.2.0")
class PipelineModel extends Model[PipelineModel] with MLWritable with Logging
Represents a fitted pipeline.
Represents a fitted pipeline.
Annotations
@Since("1.2.0")
abstract class PipelineStage extends Params with Logging
A stage in a pipeline, either an Estimator or a Transformer.
abstract class PredictionModel[FeaturesType, M <: PredictionModel[FeaturesType, M]] extends Model[M] with PredictorParams
Abstraction for a model for prediction tasks (regression and classification).
Abstraction for a model for prediction tasks (regression and classification).
FeaturesType
Type of features. E.g., VectorUDT for vector features.
M
Specialization of PredictionModel. If you subclass this type, use this type parameter to specify the concrete type for the corresponding model.
abstract class Predictor[FeaturesType, Learner <: Predictor[FeaturesType, Learner, M], M <: PredictionModel[FeaturesType, M]] extends Estimator[M] with PredictorParams
Abstraction for prediction problems (regression and classification).
Abstraction for prediction problems (regression and classification). It accepts all NumericType labels and will automatically cast it to DoubleType in fit(). If this predictor supports weights, it accepts all NumericType weights, which will be automatically casted to DoubleType in fit().
FeaturesType
Type of features. E.g., VectorUDT for vector features.
Learner
Specialization of this class. If you subclass this type, use this type parameter to specify the concrete type.
M
Specialization of PredictionModel. If you subclass this type, use this type parameter to specify the concrete type for the corresponding model.
case class SaveInstanceEnd(path: String) extends MLEvent with Product with Serializable
Event fired after MLWriter.save.
Event fired after MLWriter.save.
Annotations
@Evolving()
case class SaveInstanceStart(path: String) extends MLEvent with Product with Serializable
Event fired before MLWriter.save.
Event fired before MLWriter.save.
Annotations
@Evolving()
case class TransformEnd() extends MLEvent with Product with Serializable
Event fired after Transformer.transform.
Event fired after Transformer.transform.
Annotations
@Evolving()
case class TransformStart() extends MLEvent with Product with Serializable
Event fired before Transformer.transform.
Event fired before Transformer.transform.
Annotations
@Evolving()
abstract class Transformer extends PipelineStage
Abstract class for transformers that transform one dataset into another.
abstract class UnaryTransformer[IN, OUT, T <: UnaryTransformer[IN, OUT, T]] extends Transformer with HasInputCol with HasOutputCol with Logging
Abstract class for transformers that take one input column, apply transformation, and output the result as a new column.

Value Members

object Pipeline extends MLReadable[Pipeline] with Serializable
Annotations
@Since("1.6.0")
object PipelineModel extends MLReadable[PipelineModel] with Serializable
Annotations
@Since("1.6.0")
object functions
Annotations
@Since("3.0.0")

Packages

ML attributes

ML columns

Feature transformers

ml

package ml

Package Members

ML attributes

ML columns

Feature transformers

Type Members

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Packages

ML attributes

ML columns

Feature transformers

ml

package ml

Package Members

ML attributes

ML columns

Feature transformers

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ml