weka.filters
Class AttributeFilter

java.lang.Object
  |
  +--weka.filters.Filter
        |
        +--weka.filters.AttributeFilter

All Implemented Interfaces:

OptionHandler, java.io.Serializable

public class AttributeFilter

extends Filter

implements OptionHandler

An instance filter that deletes a range of attributes from the dataset.

Valid filter-specific options are:

-R index1,index2-index4,...
Specify list of columns to delete. First and last are valid indexes. (default none)

-V
Invert matching sense (i.e. only keep specified columns)

Author:

Len Trigg (trigg@cs.waikato.ac.nz)

See Also:

Serialized Form

Field Summary

protected int[]	m_InputStringIndex Contains an index of string attributes in the input format that will survive the filtering process
protected Range	m_SelectCols Stores which columns to select as a funky range
protected int[]	m_SelectedAttributes Stores the indexes of the selected attributes in order, once the dataset is seen

Fields inherited from class weka.filters.Filter

m_NewBatch

Constructor Summary

AttributeFilter()

Method Summary

java.lang.String	attributeIndicesTipText() Returns the tip text for this property
java.lang.String	getAttributeIndices() Get the current range selection.
boolean	getInvertSelection() Get whether the supplied columns are to be removed or kept
java.lang.String[]	getOptions() Gets the current settings of the filter.
java.lang.String	globalInfo() Returns a string describing this filter
boolean	input(Instance instance) Input an instance for filtering.
java.lang.String	invertSelectionTipText() Returns the tip text for this property
java.util.Enumeration	listOptions() Returns an enumeration describing the available options
static void	main(java.lang.String[] argv) Main method for testing this class.
void	setAttributeIndices(java.lang.String rangeList) Set which attributes are to be deleted (or kept if invert is true)
void	setAttributeIndicesArray(int[] attributes) Set which attributes are to be deleted (or kept if invert is true)
boolean	setInputFormat(Instances instanceInfo) Sets the format of the input instances.
void	setInvertSelection(boolean invert) Set whether selected columns should be removed or kept.
void	setOptions(java.lang.String[] options) Parses a given list of options controlling the behaviour of this object.

Methods inherited from class weka.filters.Filter

batchFilterFile, batchFinished, bufferInput, copyStringValues, copyStringValues, filterFile, flushInput, getInputFormat, getInputStringIndex, getOutputFormat, getOutputStringIndex, getStringIndices, inputFormat, isOutputFormatDefined, numPendingOutput, output, outputFormat, outputFormatPeek, outputPeek, push, resetQueue, setOutputFormat, useFilter

Methods inherited from class java.lang.Object

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

Field Detail

m_SelectCols

protected Range m_SelectCols

Stores which columns to select as a funky range

m_SelectedAttributes

protected int[] m_SelectedAttributes

Stores the indexes of the selected attributes in order, once the dataset is seen

m_InputStringIndex

protected int[] m_InputStringIndex

Contains an index of string attributes in the input format that will survive the filtering process

Constructor Detail

AttributeFilter

public AttributeFilter()

Method Detail

listOptions

public java.util.Enumeration listOptions()

Returns an enumeration describing the available options

Specified by:

listOptions in interface OptionHandler

Returns:

an enumeration of all the available options

setOptions

public void setOptions(java.lang.String[] options)
                throws java.lang.Exception

Parses a given list of options controlling the behaviour of this object. Valid options are:

-R index1,index2-index4,...
Specify list of columns to delete. First and last are valid indexes. (default none)

-V
Invert matching sense (i.e. only keep specified columns)

Specified by:

setOptions in interface OptionHandler

Parameters:

options - the list of options as an array of strings

Throws:

java.lang.Exception - if an option is not supported

getOptions

public java.lang.String[] getOptions()

Gets the current settings of the filter.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions

setInputFormat

public boolean setInputFormat(Instances instanceInfo)
                       throws java.lang.Exception

Sets the format of the input instances.

Overrides:

setInputFormat in class Filter

Parameters:

instanceInfo - an Instances object containing the input instance structure (any instances contained in the object are ignored - only the structure is required).

Returns:

true if the outputFormat may be collected immediately

Throws:

java.lang.Exception - if the format couldn't be set successfully

input

public boolean input(Instance instance)

Input an instance for filtering. Ordinarily the instance is processed and made available for output immediately. Some filters require all instances be read before producing output.

Overrides:

input in class Filter

Parameters:

instance - the input instance

Returns:

true if the filtered instance may now be collected with output().

Throws:

java.lang.IllegalStateException - if no input structure has been defined.

globalInfo

public java.lang.String globalInfo()

Returns a string describing this filter

Returns:

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

invertSelectionTipText

public java.lang.String invertSelectionTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getInvertSelection

public boolean getInvertSelection()

Get whether the supplied columns are to be removed or kept

Returns:

true if the supplied columns will be kept

setInvertSelection

public void setInvertSelection(boolean invert)

Set whether selected columns should be removed or kept. If true the selected columns are kept and unselected columns are deleted. If false selected columns are deleted and unselected columns are kept.

Parameters:

invert - the new invert setting

attributeIndicesTipText

public java.lang.String attributeIndicesTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getAttributeIndices

public java.lang.String getAttributeIndices()

Get the current range selection.

Returns:

a string containing a comma separated list of ranges

setAttributeIndices

public void setAttributeIndices(java.lang.String rangeList)

Set which attributes are to be deleted (or kept if invert is true)

Parameters:

rangeList - a string representing the list of attributes. Since the string will typically come from a user, attributes are indexed from 1.
eg: first-3,5,6-last

setAttributeIndicesArray

public void setAttributeIndicesArray(int[] attributes)

Set which attributes are to be deleted (or kept if invert is true)

Parameters:

attributes - an array containing indexes of attributes to select. Since the array will typically come from a program, attributes are indexed from 0.

main

public static void main(java.lang.String[] argv)

Main method for testing this class.

Parameters:

argv - should contain arguments to the filter: use -h for help