# Package weka.core

- Interface Summary
  Interface | Description
  --- | ---
  AdditionalMeasureProducer | Interface to something that can produce measures other than those calculated by evaluation modules.
  Aggregateable<E> | Interface to something that can aggregate an object of the same type with itself.
  BatchPredictor | Interface to something that can produce predictions in a batch manner when presented with a set of Instances.
  CapabilitiesHandler | Classes implementing this interface return their capabilities in regards to datasets.
  CapabilitiesIgnorer | Classes implementing this interface make it possible to turn off capabilities checking.
  CommandlineRunnable | Interface to something that can be run from the command line.
  Copyable | Interface implemented by classes that can produce "shallow" copies of their objects.
  CustomDisplayStringProvider | For classes that do not implement the OptionHandler interface and want to provide a custom display string in the GenericObjectEditor, which is more descriptive than the class name.
  DistanceFunction | Interface for any class that can compute and return distances between two instances.
  Drawable | Interface to something that can be drawn as a graph.
  EnvironmentHandler | Interface for something that can utilize environment variables.
  Instance | Interface representing an instance.
  LogHandler | Interface to something that can output messages to a log
  Matchable | Interface to something that can be matched with tree matching algorithms.
  MultiInstanceCapabilitiesHandler | Multi-Instance classifiers can specify an additional Capabilities object for the data in the relational attribute, since the format of multi-instance data is fixed to "bag/NOMINAL,data/RELATIONAL,class".
  OptionHandler | Interface to something that understands options.
  PartitionGenerator | This interface can be implemented by algorithms that generate a partition of the instance space (e.g., decision trees).
  Randomizable | Interface to something that has random behaviour that is able to be seeded with an integer.
  RevisionHandler | For classes that should return their source control revision.
  Summarizable | Interface to something that provides a short textual summary (as opposed to toString() which is usually a fairly complete description) of itself.
  TechnicalInformationHandler | For classes that are based on some kind of publications.
  ThreadSafe | Interface to something that is thread safe
  Undoable | Interface implemented by classes that support undo.
  WeightedInstancesHandler | Interface to something that makes use of the information provided by instance weights.

- Class Summary
  Class | Description
  --- | ---
  AbstractInstance | Abstract class providing common functionality for the original instance implementations.
  AlgVector | Class for performing operations on an algebraic vector of floating-point values.
  AllJavadoc | Applies all known Javadoc-derived classes to a source file.
  Attribute | Class for handling an attribute.
  AttributeExpression | A general purpose class for parsing mathematical expressions involving attribute values.
  AttributeLocator | This class locates and records the indices of a certain type of attributes, recursively in case of Relational attributes.
  AttributeMetaInfo |
  AttributeStats | A Utility class that contains summary information on an the values that appear in a dataset for a particular attribute.
  BinarySparseInstance | Class for storing a binary-data-only instance as a sparse vector.
  Capabilities | A class that describes the capabilites (e.g., handling certain types of attributes, missing values, types of classes, etc.) of a specific classifier.
  ChebyshevDistance | Implements the Chebyshev distance.
  Check | Abstract general class for testing in Weka.
  CheckGOE | Simple command line checking of classes that are editable in the GOE.
  CheckOptionHandler | Simple command line checking of classes that implement OptionHandler.
  CheckScheme | Abstract general class for testing schemes in Weka.
  CheckScheme.PostProcessor | a class for postprocessing the test-data
  ClassCache | A singleton that stores all classes on the classpath.
  ClassCache.ClassFileFilter | For filtering classes.
  ClassCache.DirectoryFilter | For filtering classes.
  ClassDiscovery | This class is used for discovering classes that implement a certain interface or a derived from a certain class.
  ClassDiscovery.StringCompare | compares two strings.
  ClassloaderUtil | Utility class that can add jar files to the classpath dynamically.
  ConjugateGradientOptimization | This subclass of Optimization.java implements conjugate gradient descent rather than BFGS updates, by overriding findArgmin(), with the same tests for convergence, and applies the same line search code.
  ContingencyTables | Class implementing some statistical routines for contingency tables.
  Copyright | A class for providing centralized Copyright information.
  DateAttributeInfo | Stores information for date attributes.
  Debug | A helper class for debug output, logging, clocking, etc.
  Debug.Clock | A little helper class for clocking and outputting times.
  Debug.DBO | contains debug methods
  Debug.Log | A helper class for logging stuff.
  Debug.Random | This extended Random class enables one to print the generated random numbers etc., before they are returned.
  Debug.SimpleLog | A little, simple helper class for logging stuff.
  Debug.Timestamp | A class that can be used for timestamps in files, The toString() method simply returns the associated Date object in a timestamp format.
  DenseInstance | Class for handling an instance.
  Environment | This class encapsulates a map of all environment and java system properties.
  EuclideanDistance | Implementing Euclidean distance (or similarity) function. One object defines not one distance but the data model in which the distances between objects of that data model can be computed. Attention: For efficiency reasons the use of consistency checks (like are the data models of the two instances exactly the same), is low. For more information, see: Wikipedia.
  FastVector<E> | Deprecated
  FilteredDistance | Applies the given filter before calling the given distance function.
  FindWithCapabilities | Locates all classes with certain capabilities.
  GlobalInfoJavadoc | Generates Javadoc comments from the class's globalInfo method.
  InstanceComparator | A comparator for the Instance class.
  Instances | Class for handling an ordered set of weighted instances.
  Javadoc | Abstract superclass for classes that generate Javadoc comments and replace the content between certain comment tags.
  ListOptions | Lists the options of an OptionHandler
  ManhattanDistance | Implements the Manhattan distance (or Taxicab geometry).
  MathematicalExpression | Class for evaluating a string adhering the following grammar:
  Matrix | Deprecated Use `weka.core.matrix.Matrix` instead - only for backwards compatibility.
  Memory | A little helper class for Memory management.
  MinkowskiDistance | Implementing Minkowski distance (or similarity) function. One object defines not one distance but the data model in which the distances between objects of that data model can be computed. Attention: For efficiency reasons the use of consistency checks (like are the data models of the two instances exactly the same), is low. For more information, see: Wikipedia.
  NominalAttributeInfo | Stores information for nominal and string attributes.
  NormalizableDistance | Represents the abstract ancestor for normalizable distance functions, like Euclidean or Manhattan distance.
  Optimization | Implementation of Active-sets method with BFGS update to solve optimization problem with only bounds constraints in multi-dimensions.
  Option | Class to store information about an option.
  OptionHandlerJavadoc | Generates Javadoc comments from the OptionHandler's options.
  PropertyPath | A helper class for accessing properties in nested objects, e.g., accessing the "getRidge" method of a LinearRegression classifier part of MultipleClassifierCombiner, e.g., Vote.
  PropertyPath.Path | Contains a (property) path structure
  PropertyPath.PathElement | Represents a single element of a property path
  ProtectedProperties | Simple class that extends the Properties class so that the properties are unable to be modified.
  Queue | Class representing a FIFO queue.
  RandomVariates | Class implementing some simple random variates generator.
  Range | Class representing a range of cardinal numbers.
  RelationalAttributeInfo | Stores information for relational attributes.
  RelationalLocator | This class locates and records the indices of relational attributes,
  RepositoryIndexGenerator | Class for generating html index files and supporting text files for a Weka package meta data repository.
  RevisionUtils | Contains utility functions for handling revisions.
  SelectedTag | Represents a selected value from a finite set of values, where each value is a Tag (i.e.
  SerializationHelper | A helper class for determining serialVersionUIDs and checking whether classes contain one and/or need one.
  SerializedObject | Class for storing an object in serialized form in memory.
  SingleIndex | Class representing a single cardinal number.
  SparseInstance | Class for storing an instance as a sparse vector.
  SpecialFunctions | Class implementing some mathematical functions.
  Statistics | Class implementing some distributions, tests, etc.
  Stopwords | Class that can test whether a given string is a stop word.
  StringLocator | This class locates and records the indices of String attributes, recursively in case of Relational attributes.
  SystemInfo | This class prints some information about the system setup, like Java version, JVM settings etc.
  Tag | A `Tag` simply associates a numeric ID with a String description.
  TechnicalInformation | Used for paper references in the Javadoc and for BibTex generation.
  TechnicalInformationHandlerJavadoc | Generates Javadoc comments from the TechnicalInformationHandler's data.
  Tee | This class pipelines print/println's to several PrintStreams.
  TestInstances | Generates artificial datasets for testing.
  Trie | A class representing a Trie data structure for strings.
  Trie.TrieIterator | Represents an iterator over a trie
  Trie.TrieNode | Represents a node in the trie.
  Utils | Class implementing some simple utility methods.
  Version | This class contains the version number of the current WEKA release and some methods for comparing another version string.
  WekaEnumeration<E> | Class for enumerating an array list's elements.
  WekaPackageManager | Class providing package management and manipulation routines.

- Enum Summary
  Enum | Description
  --- | ---
  Capabilities.Capability | enumeration of all capabilities
  RevisionUtils.Type | Enumeration of source control types.
  TechnicalInformation.Field | the possible fields
  TechnicalInformation.Type | the different types of information

- Exception Summary
  Exception | Description
  --- | ---
  NoSupportForMissingValuesException | Exception that is raised by an object that is unable to process data with missing values.
  UnassignedClassException | Exception that is raised when trying to use some data that has no class assigned to it, but a class is needed to perform the operation.
  UnassignedDatasetException | Exception that is raised when trying to use something that has no reference to a dataset, when one is required.
  UnsupportedAttributeTypeException | Exception that is raised by an object that is unable to process some of the attribute types it has been passed.
  UnsupportedClassTypeException | Exception that is raised by an object that is unable to process the class type of the data it has been passed.
  WekaException | Class for Weka-specific exceptions.