weka.filters.unsupervised.attribute
Class MathExpression

java.lang.Object
  extended by weka.filters.Filter
      extended by weka.filters.unsupervised.attribute.PotentialClassIgnorer
          extended by weka.filters.unsupervised.attribute.MathExpression
All Implemented Interfaces:
java.io.Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler, UnsupervisedFilter

public class MathExpression
extends PotentialClassIgnorer
implements UnsupervisedFilter

Modify numeric attributes according to a given expression

Valid options are:

 -unset-class-temporarily
  Unsets the class index temporarily before the filter is
  applied to the data.
  (default: no)
 -E <expression>
  Specify the expression to apply. Eg. pow(A,6)/(MEAN+MAX)
  Supported operators are +, -, *, /, pow, log,
  abs, cos, exp, sqrt, tan, sin, ceil, floor, rint, (, ), 
  MEAN, MAX, MIN, SD, COUNT, SUM, SUMSQUARED, ifelse
 -R <index1,index2-index4,...>
  Specify list of columns to ignore. First and last are valid
  indexes. (default none)
 -V
  Invert matching sense (i.e. only modify specified columns)

Version:
$Revision: 5543 $
Author:
Eibe Frank (eibe@cs.waikato.ac.nz), Prados Julien (julien.prados@cui.unige.ch)
See Also:
MathematicalExpression, Serialized Form

Field Summary
static java.lang.String m_defaultExpression
          The default modification expression
 
Constructor Summary
MathExpression()
          Constructor
 
Method Summary
 boolean batchFinished()
          Signify that this batch of input to the filter is finished.
 java.lang.String expressionTipText()
          Returns the tip text for this property
 Capabilities getCapabilities()
          Returns the Capabilities of this filter.
 java.lang.String getExpression()
          Get the expression
 java.lang.String getIgnoreRange()
          Get the current range selection.
 boolean getInvertSelection()
          Get whether the supplied columns are to be select or unselect
 java.lang.String[] getOptions()
          Gets the current settings of the filter.
 java.lang.String getRevision()
          Returns the revision string.
 java.lang.String globalInfo()
          Returns a string describing this filter
 java.lang.String ignoreRangeTipText()
          Returns the tip text for this property
 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 setExpression(java.lang.String expr)
          Set the expression to apply
 void setIgnoreRange(java.lang.String rangeList)
          Set which attributes are to be ignored
 boolean setInputFormat(Instances instanceInfo)
          Sets the format of the input instances.
 void setInvertSelection(boolean invert)
          Set whether selected columns should be select or unselect.
 void setOptions(java.lang.String[] options)
          Parses a given list of options.
 
Methods inherited from class weka.filters.unsupervised.attribute.PotentialClassIgnorer
getIgnoreClass, getOutputFormat, ignoreClassTipText, setIgnoreClass
 
Methods inherited from class weka.filters.Filter
batchFilterFile, filterFile, getCapabilities, isFirstBatchDone, isNewBatch, isOutputFormatDefined, makeCopies, makeCopy, numPendingOutput, output, outputPeek, toString, useFilter, wekaStaticWrapper
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

m_defaultExpression

public static final java.lang.String m_defaultExpression
The default modification expression

See Also:
Constant Field Values
Constructor Detail

MathExpression

public MathExpression()
Constructor

Method Detail

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

getCapabilities

public Capabilities getCapabilities()
Returns the Capabilities of this filter.

Specified by:
getCapabilities in interface CapabilitiesHandler
Overrides:
getCapabilities in class Filter
Returns:
the capabilities of this object
See Also:
Capabilities

setInputFormat

public boolean setInputFormat(Instances instanceInfo)
                       throws java.lang.Exception
Sets the format of the input instances.

Overrides:
setInputFormat in class PotentialClassIgnorer
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 input format can't be set successfully

input

public boolean input(Instance instance)
              throws java.lang.Exception
Input an instance for filtering. Filter requires all training 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 format has been set.
java.lang.NullPointerException - if the input format has not been defined.
java.lang.Exception - if the input instance was not of the correct format or if there was a problem with the filtering.

batchFinished

public boolean batchFinished()
                      throws java.lang.Exception
Signify 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
java.lang.NullPointerException - if no input structure has been defined,
java.lang.Exception - if there was a problem finishing the batch.

setOptions

public void setOptions(java.lang.String[] options)
                throws java.lang.Exception
Parses a given list of options.

Valid options are:

 -unset-class-temporarily
  Unsets the class index temporarily before the filter is
  applied to the data.
  (default: no)
 -E <expression>
  Specify the expression to apply. Eg. pow(A,6)/(MEAN+MAX)
  Supported operators are +, -, *, /, pow, log,
  abs, cos, exp, sqrt, tan, sin, ceil, floor, rint, (, ), 
  MEAN, MAX, MIN, SD, COUNT, SUM, SUMSQUARED, ifelse
 -R <index1,index2-index4,...>
  Specify list of columns to ignore. First and last are valid
  indexes. (default none)
 -V
  Invert matching sense (i.e. only modify specified columns)

Specified by:
setOptions in interface OptionHandler
Overrides:
setOptions in class PotentialClassIgnorer
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
Overrides:
getOptions in class PotentialClassIgnorer
Returns:
an array of strings suitable for passing to setOptions

listOptions

public java.util.Enumeration listOptions()
Returns an enumeration describing the available options.

Specified by:
listOptions in interface OptionHandler
Overrides:
listOptions in class PotentialClassIgnorer
Returns:
an enumeration of all the available options.

expressionTipText

public java.lang.String expressionTipText()
Returns the tip text for this property

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

setExpression

public void setExpression(java.lang.String expr)
Set the expression to apply

Parameters:
expr - a mathematical expression to apply

getExpression

public java.lang.String getExpression()
Get the expression

Returns:
the expression

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 select or unselect

Returns:
true if the supplied columns will be kept

setInvertSelection

public void setInvertSelection(boolean invert)
Set whether selected columns should be select or unselect. If true the selected columns are modified. If false the selected columns are not modified.

Parameters:
invert - the new invert setting

ignoreRangeTipText

public java.lang.String ignoreRangeTipText()
Returns the tip text for this property

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

getIgnoreRange

public java.lang.String getIgnoreRange()
Get the current range selection.

Returns:
a string containing a comma separated list of ranges

setIgnoreRange

public void setIgnoreRange(java.lang.String rangeList)
Set which attributes are to be ignored

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

getRevision

public java.lang.String getRevision()
Returns the revision string.

Specified by:
getRevision in interface RevisionHandler
Overrides:
getRevision in class Filter
Returns:
the revision

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