Package weka.core.converters

Class C45Loader

java.lang.Object

weka.core.converters.AbstractLoader

weka.core.converters.AbstractFileLoader

weka.core.converters.C45Loader

All Implemented Interfaces:

Serializable, BatchConverter, FileSourcedConverter, IncrementalConverter, Loader, EnvironmentHandler, RevisionHandler

public class C45Loader
extends AbstractFileLoader
implements BatchConverter, IncrementalConverter

Reads a file that is C45 format. Can take a filestem or filestem with .names or .data appended. Assumes that path/<filestem>.names and path/<filestem>.data exist and contain the names and data respectively.

Version:

$Revision$

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Loader, Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface weka.core.converters.Loader

Loader.StructureNotReadyException

Field Summary

Fields

Modifier and Type	Field	Description
static String	FILE_EXTENSION	the file extension

Fields inherited from class weka.core.converters.AbstractFileLoader

FILE_EXTENSION_COMPRESSED

Fields inherited from interface weka.core.converters.Loader

BATCH, INCREMENTAL, NONE

Constructor Summary

Constructors

Constructor	Description
C45Loader()

Method Summary

Modifier and Type	Method	Description
Instances	getDataSet()	Return the full data set.
String	getFileDescription()	Returns a description of the file type.
String	getFileExtension()	Get the file extension used for arff files
String[]	getFileExtensions()	Gets all the file extensions used for this type of file
Instance	getNextInstance(Instances structure)	Read the data set incrementally---get the next instance in the data set or returns null if there are no more instances to get.
String	getRevision()	Returns the revision string.
Instances	getStructure()	Determines and returns (if possible) the structure (internally the header) of the data set as an empty set of instances.
String	globalInfo()	Returns a string describing this attribute evaluator
static void	main(String[] args)	Main method for testing this class.
void	reset()	Resets the Loader ready to read a new data set or the same data set again.
void	setSource(File file)	Resets the Loader object and sets the source of the data set to be the supplied File object.

Methods inherited from class weka.core.converters.AbstractFileLoader

getUseRelativePath, retrieveFile, runFileLoader, setEnvironment, setFile, setUseRelativePath, useRelativePathTipText

Methods inherited from class weka.core.converters.AbstractLoader

setRetrieval, setSource

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

FILE_EXTENSION

public static String FILE_EXTENSION

the file extension

Constructor Detail

C45Loader

public C45Loader()

Method Detail

globalInfo

public String globalInfo()

Returns a string describing this attribute evaluator

Returns:

a description of the evaluator suitable for displaying in the explorer/experimenter gui

reset

public void reset()
           throws IOException

Resets the Loader ready to read a new data set or the same data set again.

Specified by:

reset in interface Loader

Overrides:

reset in class AbstractFileLoader

Throws:

IOException - if something goes wrong

getFileExtension

public String getFileExtension()

Get the file extension used for arff files

Specified by:

getFileExtension in interface FileSourcedConverter

Returns:

the file extension

getFileExtensions

public String[] getFileExtensions()

Gets all the file extensions used for this type of file

Specified by:

getFileExtensions in interface FileSourcedConverter

Returns:

the file extensions

getFileDescription

public String getFileDescription()

Returns a description of the file type.

Specified by:

getFileDescription in interface FileSourcedConverter

Returns:

a short file description

setSource

public void setSource(File file)
               throws IOException

Resets the Loader object and sets the source of the data set to be the supplied File object.

Specified by:

setSource in interface Loader

Overrides:

setSource in class AbstractFileLoader

Parameters:

file - the source file.

Throws:

IOException - if an error occurs

getStructure

public Instances getStructure()
                       throws IOException

Determines and returns (if possible) the structure (internally the header) of the data set as an empty set of instances.

Specified by:

getStructure in interface Loader

Specified by:

getStructure in class AbstractLoader

Returns:

the structure of the data set as an empty set of Instances

Throws:

IOException - if an error occurs

getDataSet

public Instances getDataSet()
                     throws IOException

Return the full data set. If the structure hasn't yet been determined by a call to getStructure then method should do so before processing the rest of the data set.

Specified by:

getDataSet in interface Loader

Specified by:

getDataSet in class AbstractLoader

Returns:

the structure of the data set as an empty set of Instances

Throws:

IOException - if there is no source or parsing fails

getNextInstance

public Instance getNextInstance(Instances structure)
                         throws IOException

Read the data set incrementally---get the next instance in the data set or returns null if there are no more instances to get. If the structure hasn't yet been determined by a call to getStructure then method should do so before returning the next instance in the data set. If it is not possible to read the data set incrementally (ie. in cases where the data set structure cannot be fully established before all instances have been seen) then an exception should be thrown.

Specified by:

getNextInstance in interface Loader

Specified by:

getNextInstance in class AbstractLoader

Parameters:

structure - the dataset header information, will get updated in case of string or relational attributes

Returns:

the next instance in the data set as an Instance object or null if there are no more instances to be read

Throws:

IOException - if there is an error during parsing

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision

main

public static void main(String[] args)

Main method for testing this class.

Parameters:

args - should contain <filestem>[.names | data]