weka.filters.unsupervised.attribute
Class Standardize

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

public class Standardize
extends PotentialClassIgnorer
implements UnsupervisedFilter, Sourcable

Standardizes all numeric attributes in the given dataset to have zero mean and unit variance (apart from the class attribute, if set).

Valid options are:

 -unset-class-temporarily
  Unsets the class index temporarily before the filter is
  applied to the data.
  (default: no)

Version:
$Revision: 5547 $
Author:
Eibe Frank (eibe@cs.waikato.ac.nz)
See Also:
Serialized Form

Constructor Summary
Standardize()
           
 
Method Summary
 boolean batchFinished()
          Signify that this batch of input to the filter is finished.
 Capabilities getCapabilities()
          Returns the Capabilities of this filter.
 java.lang.String getRevision()
          Returns the revision string.
 java.lang.String globalInfo()
          Returns a string describing this filter
 boolean input(Instance instance)
          Input an instance for filtering.
static void main(java.lang.String[] argv)
          Main method for testing this class.
 boolean setInputFormat(Instances instanceInfo)
          Sets the format of the input instances.
 java.lang.String toSource(java.lang.String className, Instances data)
          Returns a string that describes the filter as source.
 
Methods inherited from class weka.filters.unsupervised.attribute.PotentialClassIgnorer
getIgnoreClass, getOptions, getOutputFormat, ignoreClassTipText, listOptions, setIgnoreClass, setOptions
 
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
 

Constructor Detail

Standardize

public Standardize()
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.Exception - if an error occurs
java.lang.IllegalStateException - if no input structure has been defined

toSource

public java.lang.String toSource(java.lang.String className,
                                 Instances data)
                          throws java.lang.Exception
Returns a string that describes the filter as source. The filter will be contained in a class with the given name (there may be auxiliary classes), and will contain two methods with these signatures:

 // converts one row
 public static Object[] filter(Object[] i);
 // converts a full dataset (first dimension is row index)
 public static Object[][] filter(Object[][] i);
 
where the array i contains elements that are either Double, String, with missing values represented as null. The generated code is public domain and comes with no warranty.

Specified by:
toSource in interface Sourcable
Parameters:
className - the name that should be given to the source class.
data - the dataset used for initializing the filter
Returns:
the object source described by a string
Throws:
java.lang.Exception - if the source can't be computed

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