类 AddExpression

java.lang.Object
weka.filters.Filter
weka.filters.unsupervised.attribute.AddExpression
所有已实现的接口:
Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler, StreamableFilter, UnsupervisedFilter

public class AddExpression extends Filter implements UnsupervisedFilter, StreamableFilter, OptionHandler
An instance filter that creates a new attribute by applying a mathematical expression to existing attributes. The expression can contain attribute references and numeric constants. Supported operators are :
+, -, *, /, ^, log, abs, cos, exp, sqrt, floor, ceil, rint, tan, sin, (, )
Attributes are specified by prefixing with 'a', eg. a7 is attribute number 7 (starting from 1).
Example expression : a1^2*a5/log(a7*4.0).

Valid options are:

 -E <expression>
  Specify the expression to apply. Eg a1^2*a5/log(a7*4.0).
  Supported opperators: ,+, -, *, /, ^, log, abs, cos, 
  exp, sqrt, floor, ceil, rint, tan, sin, (, )
  (default: a1^2)
 -N <name>
  Specify the name for the new attribute. (default is the expression provided with -E)
 -D
  Debug. Names attribute with the postfix parse of the expression.
版本:
$Revision: 5543 $
作者:
Mark Hall (mhall@cs.waikato.ac.nz)
另请参阅:
  • 构造器详细资料

    • AddExpression

      public AddExpression()
  • 方法详细资料

    • globalInfo

      public String globalInfo()
      Returns a string describing this filter
      返回:
      a description of the filter suitable for displaying in the explorer/experimenter gui
    • listOptions

      public Enumeration listOptions()
      Returns an enumeration describing the available options.
      指定者:
      listOptions 在接口中 OptionHandler
      返回:
      an enumeration of all the available options.
    • setOptions

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

      Valid options are:

       -E <expression>
        Specify the expression to apply. Eg a1^2*a5/log(a7*4.0).
        Supported opperators: ,+, -, *, /, ^, log, abs, cos, 
        exp, sqrt, floor, ceil, rint, tan, sin, (, )
        (default: a1^2)
       -N <name>
        Specify the name for the new attribute. (default is the expression provided with -E)
       -D
        Debug. Names attribute with the postfix parse of the expression.
      指定者:
      setOptions 在接口中 OptionHandler
      参数:
      options - the list of options as an array of strings
      抛出:
      Exception - if an option is not supported
    • getOptions

      public String[] getOptions()
      Gets the current settings of the filter.
      指定者:
      getOptions 在接口中 OptionHandler
      返回:
      an array of strings suitable for passing to setOptions
    • nameTipText

      public String nameTipText()
      Returns the tip text for this property
      返回:
      tip text for this property suitable for displaying in the explorer/experimenter gui
    • setName

      public void setName(String name)
      Set the name for the new attribute. The string "expression" can be used to make the name of the new attribute equal to the expression provided.
      参数:
      name - the name of the new attribute
    • getName

      public String getName()
      Returns the name of the new attribute
      返回:
      the name of the new attribute
    • debugTipText

      public String debugTipText()
      Returns the tip text for this property
      返回:
      tip text for this property suitable for displaying in the explorer/experimenter gui
    • setDebug

      public void setDebug(boolean d)
      Set debug mode. Causes the new attribute to be named with the postfix parse of the expression
      参数:
      d - true if debug mode is to be used
    • getDebug

      public boolean getDebug()
      Gets whether debug is set
      返回:
      true if debug is set
    • expressionTipText

      public String expressionTipText()
      Returns the tip text for this property
      返回:
      tip text for this property suitable for displaying in the explorer/experimenter gui
    • setExpression

      public void setExpression(String expr)
      Set the expression to apply
      参数:
      expr - a mathematical expression to apply
    • getExpression

      public String getExpression()
      Get the expression
      返回:
      the expression
    • getCapabilities

      public Capabilities getCapabilities()
      Returns the Capabilities of this filter.
      指定者:
      getCapabilities 在接口中 CapabilitiesHandler
      覆盖:
      getCapabilities 在类中 Filter
      返回:
      the capabilities of this object
      另请参阅:
    • setInputFormat

      public boolean setInputFormat(Instances instanceInfo) throws Exception
      Sets the format of the input instances.
      覆盖:
      setInputFormat 在类中 Filter
      参数:
      instanceInfo - an Instances object containing the input instance structure (any instances contained in the object are ignored - only the structure is required).
      返回:
      true if the outputFormat may be collected immediately
      抛出:
      Exception - if the format couldn't be set successfully
    • input

      public boolean input(Instance instance) throws Exception
      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.
      覆盖:
      input 在类中 Filter
      参数:
      instance - the input instance
      返回:
      true if the filtered instance may now be collected with output().
      抛出:
      IllegalStateException - if no input format has been defined.
      Exception - if there was a problem during the filtering.
    • getRevision

      public String getRevision()
      Returns the revision string.
      指定者:
      getRevision 在接口中 RevisionHandler
      覆盖:
      getRevision 在类中 Filter
      返回:
      the revision
    • main

      public static void main(String[] args)
      Main method for testing this class.
      参数:
      args - should contain arguments to the filter: use -h for help