com.rapidminer.operator.features.construction
Class AttributeConstruction

java.lang.Object
  com.rapidminer.operator.Operator
      com.rapidminer.operator.AbstractExampleSetProcessing
          com.rapidminer.operator.features.AbstractFeatureProcessing
              com.rapidminer.operator.features.construction.AbstractFeatureConstruction
                  com.rapidminer.operator.features.construction.AttributeConstruction

All Implemented Interfaces:

ConfigurationListener, PreviewListener, ParameterHandler, LoggingHandler

public class AttributeConstruction
extends AbstractFeatureConstruction

This operator constructs new attributes from the attributes of the input example set. The names of the new attributes and their construction description are defined in the parameter list "functions".

The following operators are supported:

• Addition: +
• Subtraction: -
• Multiplication: *
• Division: /
• Power: ^
• Modulus: %
• Less Than: <
• Greater Than: >
• Less or Equal: <=
• More or Equal: >=
• Equal: ==
• Not Equal: !=
• Boolean Not: !
• Boolean And: two ampers and
• Boolean Or: ||

The following log and exponential functions are supported:

• Natural Logarithm: ln(x)
• Logarithm Base 10: log(x)
• Logarithm Dualis (Base 2): ld(x)
• Exponential (e^x): exp(x)
• Power: pow(x,y)

The following trigonometric functions are supported:

• Sine: sin(x)
• Cosine: cos(x)
• Tangent: tan(x)
• Arc Sine: asin(x)
• Arc Cosine: acos(x)
• Arc Tangent: atan(x)
• Arc Tangent (with 2 parameters): atan2(x,y)
• Hyperbolic Sine: sinh(x)
• Hyperbolic Cosine: cosh(x)
• Hyperbolic Tangent: tanh(x)
• Inverse Hyperbolic Sine: asinh(x)
• Inverse Hyperbolic Cosine: acosh(x)
• Inverse Hyperbolic Tangent: atanh(x)

The following statistical functions are supported:

• Round: round(x)
• Round to p decimals: round(x,p)
• Floor: floor(x)
• Ceiling: ceil(x)
• Average: avg(x,y,z...)
• Minimum: min(x,y,z...)
• Maximum: max(x,y,z...)

The following miscellaneous functions are supported:

• If-Then-Else: if(cond,true-evaluation, false-evaluation)
• Absolute: abs(x)
• Square Root: sqrt(x)
• Signum (delivers the sign of a number): sgn(x)
• Random Number (between 0 and 1): rand()
• Modulus (x % y): mod(x,y)
• Sum of k Numbers: sum(x,y,z...)
• Binomial Coefficients: binom(n, i)
• Number to String: str(x)
• String to Number: parse(x)
• Substring: cut(x, start, len)

The following process related functions are supported:

• Retrieving a parameter value: param("operator", "parameter")

Beside those operations and functions, this operator also supports the constants pi and e if this is indicated by the corresponding parameter (default: true). You can also use strings in formulas (for example in a conditioned if-formula) but the string values have to be enclosed in double quotes.

Please note that there are some restrictions for the attribute names in order to let this operator work properly:

• If the standard constants are usable, attribute names with names like "e" or "pi" are not allowed.
• Attribute names with function or operator names are also not allowed.
• Attribute names containing parentheses are not allowed.

If these conditions are not fulfilled, the names must be changed beforehand, for example with the ChangeAttributeName operator.

Examples:
a1+sin(a2*a3)
if (att1>5, att2*att3, -abs(att1))

Author:

Ingo Mierswa

Field Summary

static java.lang.String	PARAMETER_FUNCTIONS The parameter name for "List of functions to generate.
static java.lang.String	PARAMETER_KEEP_ALL The parameter name for "If set to true, all the original attributes are kept, otherwise they are removed from the example set.
static java.lang.String	PARAMETER_USE_STANDARD_CONSTANTS Indicates if standard constants like e or pi should be available.

Constructor Summary

AttributeConstruction(OperatorDescription description)

Method Summary

ExampleSet	apply(ExampleSet exampleSet) Delegate for the apply method.
java.util.List<ParameterType>	getParameterTypes() Returns a list of ParameterTypes describing the parameters of this operator.

Methods inherited from class com.rapidminer.operator.AbstractExampleSetProcessing

apply, getInputClasses, getOutputClasses

Methods inherited from class com.rapidminer.operator.Operator

addError, addValue, addWarning, apply, checkDeprecations, checkForStop, checkIO, checkProperties, clearErrorList, cloneOperator, createExperimentTree, createExperimentTree, createFromXML, createMarkedExperimentTree, createMarkedProcessTree, createProcessTree, createProcessTree, getAddOnlyAdditionalOutput, getApplyCount, getDeliveredOutputClasses, getDeprecationInfo, getDesiredInputClasses, getEncoding, getErrorList, getExperiment, getInnerOperatorsXML, getInput, getInput, getInput, getInputDescription, getIOContainerForInApplyLoopBreakpoint, getIODescription, getLog, getName, getOperatorClassName, getOperatorDescription, getParameter, getParameterAsBoolean, getParameterAsColor, getParameterAsDouble, getParameterAsFile, getParameterAsFile, getParameterAsInputStream, getParameterAsInt, getParameterAsMatrix, getParameterAsString, getParameterList, getParameters, getParameterType, getParent, getProcess, getStartTime, getStatus, getUserDescription, getValue, getValues, getXML, hasBreakpoint, hasBreakpoint, hasInput, inApplyLoop, isDebugMode, isEnabled, isExpanded, isParallel, isParameterSet, log, logError, logNote, logWarning, performAdditionalChecks, processFinished, processStarts, register, registerOperator, remove, rename, resume, setApplyCount, setBreakpoint, setEnabled, setExpanded, setInput, setListParameter, setOperatorParameters, setParameter, setParameters, setParent, setUserDescription, toString, unregisterOperator, writeXML

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

PARAMETER_FUNCTIONS

public static final java.lang.String PARAMETER_FUNCTIONS

The parameter name for "List of functions to generate."

See Also:

Constant Field Values

PARAMETER_USE_STANDARD_CONSTANTS

public static final java.lang.String PARAMETER_USE_STANDARD_CONSTANTS

Indicates if standard constants like e or pi should be available.

See Also:

Constant Field Values

PARAMETER_KEEP_ALL

public static final java.lang.String PARAMETER_KEEP_ALL

The parameter name for "If set to true, all the original attributes are kept, otherwise they are removed from the example set."

See Also:

Constant Field Values

Constructor Detail

AttributeConstruction

public AttributeConstruction(OperatorDescription description)

Method Detail

apply

public ExampleSet apply(ExampleSet exampleSet)
                 throws OperatorException

Description copied from class: AbstractExampleSetProcessing

Delegate for the apply method. In most cases, the returned example set will be the same as the example set or a modified clone.

Specified by:

apply in class AbstractExampleSetProcessing

Throws:

OperatorException

getParameterTypes

public java.util.List<ParameterType> getParameterTypes()

Description copied from class: Operator

Returns a list of ParameterTypes describing the parameters of this operator. The default implementation returns an empty list if no input objects can be retained and special parameters for those input objects which can be prevented from being consumed.

Specified by:

getParameterTypes in interface ParameterHandler

Overrides:

getParameterTypes in class Operator