weka.filters
Class StringToNominalFilter

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

All Implemented Interfaces:

OptionHandler, java.io.Serializable

public class StringToNominalFilter

extends Filter

implements OptionHandler

Converts a string attribute (i.e. unspecified number of values) to nominal (i.e. set number of values). You should ensure that all string values that will appear are represented in the dataset.

Valid filter-specific options are:

-C col
Index of the attribute to be changed. (default last)

Author:

Len Trigg (len@intelligenesis.net)

See Also:

Serialized Form

Fields inherited from class weka.filters.Filter

m_NewBatch

Constructor Summary

StringToNominalFilter()

Method Summary

boolean	batchFinished() Signifies that this batch of input to the filter is finished.
int	getAttributeIndex() Get the index of the attribute used.
java.lang.String[]	getOptions() Gets the current settings of the filter.
boolean	input(Instance instance) Input an instance for filtering.
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	setAttributeIndex(int attIndex) Sets index of the attribute used.
boolean	setInputFormat(Instances instanceInfo) Sets the format of the input instances.
void	setOptions(java.lang.String[] options) Parses the options for this object.

Methods inherited from class weka.filters.Filter

batchFilterFile, 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

Constructor Detail

StringToNominalFilter

public StringToNominalFilter()

Method Detail

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:

UnsupportedAttributeTypeException - if the selected attribute a string attribute.

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

input

public boolean input(Instance instance)

Input an instance for filtering. The instance is processed and made available for output immediately.

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.

batchFinished

public boolean batchFinished()

Signifies that this batch of input to the filter is finished. If the filter requires all instances prior to filtering, output() may now be called to retrieve the filtered instances.

Overrides:

batchFinished in class Filter

Returns:

true if there are instances pending output.

Throws:

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

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 the options for this object. Valid options are:

-C col
The column containing the values to be merged. (default last)

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

getAttributeIndex

public int getAttributeIndex()

Get the index of the attribute used.

Returns:

the index of the attribute

setAttributeIndex

public void setAttributeIndex(int attIndex)

Sets index of the attribute used.

Parameters:

index - the index of the attribute

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