Package weka.core

Class Capabilities

java.lang.Object
weka.core.Capabilities
All Implemented Interfaces:
Serializable, Cloneable, RevisionHandler
public class Capabilities extends Object implements Cloneable, Serializable, RevisionHandler
A class that describes the capabilites (e.g., handling certain types of attributes, missing values, types of classes, etc.) of a specific classifier. By default, the classifier is capable of nothing. This ensures that new features have to be enabled explicitly.

A common code fragment for making use of the capabilities in a classifier would be this: 

 public void buildClassifier(Instances instances) throws Exception {
   // can the classifier handle the data?
   getCapabilities().testWithFail(instances);
   ...
   // possible deletion of instances with missing class labels, etc.
For only testing a single attribute, use this: 
   ...
   Attribute att = instances.attribute(0);
   getCapabilities().testWithFail(att);
   ...
Or for testing the class attribute (uses the capabilities that are especially for the class): 
   ...
   Attribute att = instances.classAttribute();
   getCapabilities().testWithFail(att, true);
   ...
Version:
$Revision: 14512 $
Author:
FracPete (fracpete at waikato dot ac dot nz)
See Also:

  • Field Details

    • PROPERTIES_FILE

      public static final String PROPERTIES_FILE
      the properties file for managing the tests
      See Also:

  • Constructor Details

    • Capabilities

      public Capabilities(CapabilitiesHandler owner)
      initializes the capabilities for the given owner
      Parameters:
      owner - the object that produced this Capabilities instance

  • Method Details

    • doNotCheckCapabilities

      public boolean doNotCheckCapabilities()
      Does owner implement CapabilitiesIgnorer and does it not want capability checking to be performed?

    • clone

      public Object clone()
      Creates and returns a copy of this object.
      Returns:
      a clone of this object

    • assign

      public void assign(Capabilities c)
      retrieves the data from the given Capabilities object
      Parameters:
      c - the capabilities object to initialize with

    • and

      public void and(Capabilities c)
      performs an AND conjunction with the capabilities of the given Capabilities object and updates itself
      Parameters:
      c - the capabilities to AND with

    • or

      public void or(Capabilities c)
      performs an OR conjunction with the capabilities of the given Capabilities object and updates itself
      Parameters:
      c - the capabilities to OR with

    • supports

      public boolean supports(Capabilities c)
      Returns true if the currently set capabilities support at least all of the capabilities of the given Capabilities object (checks only the enum!)
      Parameters:
      c - the capabilities to support at least
      Returns:
      true if all the requested capabilities are supported

    • supportsMaybe

      public boolean supportsMaybe(Capabilities c)
      Returns true if the currently set capabilities support (or have a dependency) at least all of the capabilities of the given Capabilities object (checks only the enum!)
      Parameters:
      c - the capabilities (or dependencies) to support at least
      Returns:
      true if all the requested capabilities are supported (or at least have a dependency)

    • setOwner

      public void setOwner(CapabilitiesHandler value)
      sets the owner of this capabilities object
      Parameters:
      value - the new owner

    • getOwner

      public CapabilitiesHandler getOwner()
      returns the owner of this capabilities object
      Returns:
      the current owner of this capabilites object

    • setMinimumNumberInstances

      public void setMinimumNumberInstances(int value)
      sets the minimum number of instances that have to be in the dataset
      Parameters:
      value - the minimum number of instances

    • getMinimumNumberInstances

      public int getMinimumNumberInstances()
      returns the minimum number of instances that have to be in the dataset
      Returns:
      the minimum number of instances

    • capabilities

      public Iterator<Capabilities.Capability> capabilities()
      Returns an Iterator over the stored capabilities
      Returns:
      iterator over the current capabilities

    • dependencies

      public Iterator<Capabilities.Capability> dependencies()
      Returns an Iterator over the stored dependencies
      Returns:
      iterator over the current dependencies

    • enable

      public void enable(Capabilities.Capability c)
      enables the given capability. Enabling NOMINAL_ATTRIBUTES also enables BINARY_ATTRIBUTES, UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Enabling BINARY_ATTRIBUTES also enables UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Enabling UNARY_ATTRIBUTES also enables EMPTY_NOMINAL_ATTRIBUTES. But NOMINAL_CLASS only enables BINARY_CLASS, since normal schemes in Weka don't work with datasets that have only 1 class label (or none).
      Parameters:
      c - the capability to enable

    • enableDependency

      public void enableDependency(Capabilities.Capability c)
      enables the dependency flag for the given capability Enabling NOMINAL_ATTRIBUTES also enables BINARY_ATTRIBUTES, UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Enabling BINARY_ATTRIBUTES also enables UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Enabling UNARY_ATTRIBUTES also enables EMPTY_NOMINAL_ATTRIBUTES. But NOMINAL_CLASS only enables BINARY_CLASS, since normal schemes in Weka don't work with datasets that have only 1 class label (or none).
      Parameters:
      c - the capability to enable the dependency flag for

    • enableAllClasses

      public void enableAllClasses()
      enables all class types
      See Also:

    • enableAllClassDependencies

      public void enableAllClassDependencies()
      enables all class type dependencies
      See Also:

    • enableAllAttributes

      public void enableAllAttributes()
      enables all attribute types
      See Also:

    • enableAllAttributeDependencies

      public void enableAllAttributeDependencies()
      enables all attribute type dependencies
      See Also:

    • enableAll

      public void enableAll()
      enables all attribute and class types (including dependencies)

    • disable

      public void disable(Capabilities.Capability c)
      disables the given capability Disabling NOMINAL_ATTRIBUTES also disables BINARY_ATTRIBUTES, UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Disabling BINARY_ATTRIBUTES also disables UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Disabling UNARY_ATTRIBUTES also disables EMPTY_NOMINAL_ATTRIBUTES. The same hierarchy applies to the class capabilities.
      Parameters:
      c - the capability to disable

    • disableDependency

      public void disableDependency(Capabilities.Capability c)
      disables the dependency of the given capability Disabling NOMINAL_ATTRIBUTES also disables BINARY_ATTRIBUTES, UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Disabling BINARY_ATTRIBUTES also disables UNARY_ATTRIBUTES and EMPTY_NOMINAL_ATTRIBUTES. Disabling UNARY_ATTRIBUTES also disables EMPTY_NOMINAL_ATTRIBUTES. The same hierarchy applies to the class capabilities.
      Parameters:
      c - the capability to disable the dependency flag for

    • disableAllClasses

      public void disableAllClasses()
      disables all class types
      See Also:

    • disableAllClassDependencies

      public void disableAllClassDependencies()
      disables all class type dependencies
      See Also:

    • disableAllAttributes

      public void disableAllAttributes()
      disables all attribute types
      See Also:

    • disableAllAttributeDependencies

      public void disableAllAttributeDependencies()
      disables all attribute type dependencies
      See Also:

    • disableAll

      public void disableAll()
      disables all attribute and class types (including dependencies)

    • getClassCapabilities

      public Capabilities getClassCapabilities()
      returns all class capabilities
      Returns:
      all capabilities regarding the class
      See Also:

    • getAttributeCapabilities

      public Capabilities getAttributeCapabilities()
      returns all attribute capabilities
      Returns:
      all capabilities regarding attributes
      See Also:

    • getOtherCapabilities

      public Capabilities getOtherCapabilities()
      returns all other capabilities, besides class and attribute related ones
      Returns:
      all other capabilities, besides class and attribute related ones

    • handles

      public boolean handles(Capabilities.Capability c)
      returns true if the classifier handler has the specified capability
      Parameters:
      c - the capability to test
      Returns:
      true if the classifier handler has the capability

    • hasDependency

      public boolean hasDependency(Capabilities.Capability c)
      returns true if the classifier handler has a dependency for the specified capability
      Parameters:
      c - the capability to test
      Returns:
      true if the classifier handler has a dependency for the capability

    • hasDependencies

      public boolean hasDependencies()
      Checks whether there are any dependencies at all
      Returns:
      true if there is at least one dependency for a capability

    • getFailReason

      public Exception getFailReason()
      returns the reason why the tests failed, is null if tests succeeded
      Returns:
      the reason why the tests failed

    • test

      public boolean test(Attribute att)
      Test the given attribute, whether it can be processed by the handler, given its capabilities. The method assumes that the specified attribute is not the class attribute.
      Parameters:
      att - the attribute to test
      Returns:
      true if all the tests succeeded
      See Also:

    • test

      public boolean test(Attribute att, boolean isClass)
      Test the given attribute, whether it can be processed by the handler, given its capabilities.
      Parameters:
      att - the attribute to test
      isClass - whether this attribute is the class attribute
      Returns:
      true if all the tests succeeded
      See Also:
      • m_AttributeTest

    • test

      public boolean test(Instances data)
      Tests the given data, whether it can be processed by the handler, given its capabilities. Classifiers implementing the MultiInstanceCapabilitiesHandler interface are checked automatically for their multi-instance Capabilities (if no bags, then only the bag-structure, otherwise only the first bag).
      Parameters:
      data - the data to test
      Returns:
      true if all the tests succeeded
      See Also:

    • test

      public boolean test(Instances data, int fromIndex, int toIndex)
      Tests a certain range of attributes of the given data, whether it can be processed by the handler, given its capabilities. Classifiers implementing the MultiInstanceCapabilitiesHandler interface are checked automatically for their multi-instance Capabilities (if no bags, then only the bag-structure, otherwise only the first bag).
      Parameters:
      data - the data to test
      fromIndex - the range of attributes - start (incl.)
      toIndex - the range of attributes - end (incl.)
      Returns:
      true if all the tests succeeded
      See Also:

    • testWithFail

      public void testWithFail(Attribute att) throws Exception
      tests the given attribute by calling the test(Attribute,boolean) method and throws an exception if the test fails. The method assumes that the specified attribute is not the class attribute.
      Parameters:
      att - the attribute to test
      Throws:
      Exception - in case the attribute doesn't pass the tests
      See Also:

    • testWithFail

      public void testWithFail(Attribute att, boolean isClass) throws Exception
      tests the given attribute by calling the test(Attribute,boolean) method and throws an exception if the test fails.
      Parameters:
      att - the attribute to test
      isClass - whether this attribute is the class attribute
      Throws:
      Exception - in case the attribute doesn't pass the tests
      See Also:

    • testWithFail

      public void testWithFail(Instances data, int fromIndex, int toIndex) throws Exception
      tests the given data by calling the test(Instances,int,int) method and throws an exception if the test fails.
      Parameters:
      data - the data to test
      fromIndex - the range of attributes - start (incl.)
      toIndex - the range of attributes - end (incl.)
      Throws:
      Exception - in case the data doesn't pass the tests
      See Also:

    • testWithFail

      public void testWithFail(Instances data) throws Exception
      tests the given data by calling the test(Instances) method and throws an exception if the test fails.
      Parameters:
      data - the data to test
      Throws:
      Exception - in case the data doesn't pass the tests
      See Also:

    • listCapabilities

      public String listCapabilities()
      returns a comma-separated list of all the capabilities, excluding interface-based ones.
      Returns:
      the string describing the capabilities

    • addCapabilities

      public String addCapabilities(String title)
      generates a string from the capabilities, suitable to add to the help text.
      Parameters:
      title - the title for the capabilities
      Returns:
      a string describing the capabilities

    • toString

      public String toString()
      returns a string representation of the capabilities
      Overrides:
      toString in class Object
      Returns:
      a string representation of this object

    • toSource

      public String toSource(String objectname)
      turns the capabilities object into source code. The returned source code is a block that creates a Capabilities object named 'objectname' and enables all the capabilities of this Capabilities object.
      Parameters:
      objectname - the name of the Capabilities object being instantiated
      Returns:
      the generated source code

    • toSource

      public String toSource(String objectname, int indent)
      turns the capabilities object into source code. The returned source code is a block that creates a Capabilities object named 'objectname' and enables all the capabilities of this Capabilities object.
      Parameters:
      objectname - the name of the Capabilities object being instantiated
      indent - the number of blanks to indent
      Returns:
      the generated source code

    • forInstances

      public static Capabilities forInstances(Instances data) throws Exception
      returns a Capabilities object specific for this data. The multi-instance capability is not checked as well as the minimum number of instances is not set.
      Parameters:
      data - the data to base the capabilities on
      Returns:
      a data-specific capabilities object
      Throws:
      Exception - in case an error occurrs, e.g., an unknown attribute type

    • forInstances

      public static Capabilities forInstances(Instances data, boolean multi) throws Exception
      returns a Capabilities object specific for this data. The minimum number of instances is not set, the check for multi-instance data is optional.
      Parameters:
      data - the data to base the capabilities on
      multi - if true then the structure is checked, too
      Returns:
      a data-specific capabilities object
      Throws:
      Exception - in case an error occurrs, e.g., an unknown attribute type

    • main

      public static void main(String[] args) throws Exception
      loads the given dataset and prints the Capabilities necessary to process it.

      Valid parameters:

      -file filename
      the file to load -c index the explicit index of the class attribute (default: none)

      Parameters:
      args - the commandline arguments
      Throws:
      Exception - if something goes wrong

    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Returns:
      the revision