Package weka.filters.unsupervised.attribute

Class FirstOrder

java.lang.Object
weka.filters.Filter
weka.filters.unsupervised.attribute.FirstOrder
All Implemented Interfaces:
Serializable, CapabilitiesHandler, CapabilitiesIgnorer, CommandlineRunnable, OptionHandler, RevisionHandler, WeightedInstancesHandler, StreamableFilter, UnsupervisedFilter
public class FirstOrder extends Filter implements UnsupervisedFilter, StreamableFilter, OptionHandler, WeightedInstancesHandler
This instance filter takes a range of N numeric attributes and replaces them with N-1 numeric attributes, the values of which are the difference between consecutive attribute values from the original instance. eg:

Original attribute values

0.1, 0.2, 0.3, 0.1, 0.3

New attribute values

0.1, 0.1, -0.2, 0.2

The range of attributes used is taken in numeric order. That is, a range spec of 7-11,3-5 will use the attribute ordering 3,4,5,7,8,9,10,11 for the differences, NOT 7,8,9,10,11,3,4,5.

Valid options are: 

 -R <index1,index2-index4,...>
  Specify list of columns to take the differences between.
  First and last are valid indexes.
  (default none)
Version:
$Revision: 14508 $
Author:
Len Trigg (trigg@cs.waikato.ac.nz)
See Also:

  • Constructor Details

    • FirstOrder

      public FirstOrder()

  • 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

    • listOptions

      public Enumeration<Option> listOptions()
      Returns an enumeration describing the available options.
      Specified by:
      listOptions in interface OptionHandler
      Overrides:
      listOptions in class Filter
      Returns:
      an enumeration of all the available options.

    • setOptions

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

      Valid options are: 

       -R <index1,index2-index4,...>
  Specify list of columns to take the differences between.
  First and last are valid indexes.
  (default none)
      Specified by:
      setOptions in interface OptionHandler
      Overrides:
      setOptions in class Filter
      Parameters:
      options - the list of options as an array of strings
      Throws:
      Exception - if an option is not supported

    • getOptions

      public String[] getOptions()
      Gets the current settings of the filter.
      Specified by:
      getOptions in interface OptionHandler
      Overrides:
      getOptions in class Filter
      Returns:
      an array of strings suitable for passing to setOptions

    • 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 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 any of the selected attributes are not numeric
      Exception - if only one attribute has been selected.

    • 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:
      IllegalStateException - if no input format has been defined.

    • attributeIndicesTipText

      public 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 String getAttributeIndices()
      Get the current range selection
      Returns:
      a string containing a comma separated list of ranges

    • setAttributeIndices

      public void setAttributeIndices(String rangeList) throws Exception
      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
      Throws:
      Exception - if an invalid range list is supplied

    • setAttributeIndicesArray

      public void setAttributeIndicesArray(int[] attributes) throws Exception
      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.
      Throws:
      Exception - if an invalid set of ranges is supplied

    • 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