Package weka.filters.unsupervised.attribute

Class Standardize

java.lang.Object
weka.filters.Filter
weka.filters.unsupervised.attribute.PotentialClassIgnorer
weka.filters.unsupervised.attribute.Standardize
All Implemented Interfaces:
Serializable, CapabilitiesHandler, CapabilitiesIgnorer, CommandlineRunnable, OptionHandler, RevisionHandler, WeightedAttributesHandler, WeightedInstancesHandler, Sourcable, UnsupervisedFilter
public class Standardize extends PotentialClassIgnorer implements UnsupervisedFilter, Sourcable, WeightedAttributesHandler, WeightedInstancesHandler
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: 14508 $
Author:
Eibe Frank (eibe@cs.waikato.ac.nz)
See Also:

  • Constructor Details

    • Standardize

      public Standardize()

  • Method Details

    • globalInfo

      public 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:

    • setInputFormat

      public boolean setInputFormat(Instances instanceInfo) throws 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:
      Exception - if the input format can't be set successfully

    • input

      public boolean input(Instance instance) throws 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:
      IllegalStateException - if no input format has been set.
      NullPointerException - if the input format has not been defined.
      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 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:
      Exception - if an error occurs
      IllegalStateException - if no input structure has been defined

    • toSource

      public String toSource(String className, Instances data) throws 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:
      Exception - if the source can't be computed

    • getRevision

      public 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(String[] argv)
      Main method for testing this class.
      Parameters:
      argv - should contain arguments to the filter: use -h for help