Package com.singularsys.extensions.xjep

Class ExtractEqn

java.lang.Object

com.singularsys.jep.functions.PostfixMathCommand

com.singularsys.extensions.xjep.ExtractEqn

All Implemented Interfaces:

CommandVisitorI, JepComponent, PostfixMathCommandI, Serializable

public class ExtractEqn
extends PostfixMathCommand
implements JepComponent, CommandVisitorI

Extracts the equation of a symbolic variable

 y := (x - 1)^2
 expand(eqn(y))
 

Will return x*(x+1.0)*(x-1.0).

The operation depends on the EquationExtractor class, this must be defined either by supplying an XJep instance or explicitly in a constructor.

See Also:

• CommandVisitorI
• SubstitutionVisitor
• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ExtractEqn.Type

Field Summary

Fields

Modifier and Type	Field	Description
protected EquationExtractor<?>	ee

Fields inherited from class com.singularsys.jep.functions.PostfixMathCommand

curNumberOfParameters, description, name, NaN, numberOfParameters

Constructor Summary

Constructors

Constructor	Description
ExtractEqn()	Default constructor, an XJep instance must be later defined by calling jep.reinitializeComponents().
ExtractEqn(ExtractEqn.Type type)	Constructor.
ExtractEqn(XJep xjep)	Constructor with explicit XJep instance
ExtractEqn(XJep xjep, ExtractEqn.Type type)	Constructor with jep instance and type

Method Summary

Modifier and Type	Method	Description
JepComponent	getLightWeightInstance()	Gets a light-weight instance suitable for using in multiple threads.
void	init(Jep jep)	Initialize the component.
Node	process(Node node, Node[] children)	Performs the specified action on an expression tree.

Methods inherited from class com.singularsys.jep.functions.PostfixMathCommand

asArray, asBool, asDouble, asInt, asLong, asStrictInt, asString, asType, checkNumberOfParameters, getDescription, getDescription, getDescriptionWithType, getName, getNumberOfParameters, run, setCurNumberOfParameters, setDescription, setName, toString, toString

Methods inherited from class java.lang.Object

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

Field Details

ee

protected EquationExtractor<?> ee

Constructor Details

ExtractEqn

public ExtractEqn(XJep xjep)

Constructor with explicit XJep instance

Parameters:

xjep -

ExtractEqn

public ExtractEqn()

Default constructor, an XJep instance must be later defined by calling jep.reinitializeComponents().

ExtractEqn

public ExtractEqn(ExtractEqn.Type type)

Constructor.

Parameters:

type - one of ExtractEqn.Type.DEEP, ExtractEqn.Type.TOP

Since:

Jep 4.1, extensions 2.2

ExtractEqn

public ExtractEqn(XJep xjep,
 ExtractEqn.Type type)

Constructor with jep instance and type

Parameters:

xjep - jep instance

type - type of evaluation one of ExtractEqn.Type.DEEP, ExtractEqn.Type.TOP

Since:

Jep 4.1, extensions 2.2

Method Details

process

public Node process(Node node,
 Node[] children)
             throws ParseException

Description copied from interface: CommandVisitorI

Performs the specified action on an expression tree.

Specified by:

process in interface CommandVisitorI

Parameters:

node - top node of the tree

children - the children of the node after they have been preprocessed.

Returns:

top node of the results.

Throws:

ParseException

init

public void init(Jep jep)

Description copied from interface: JepComponent

Initialize the component. This method is called whenever a component is added to Jep. Hence, it allows components to keep track of the other components they may rely on.

Specified by:

init in interface JepComponent

Parameters:

jep - the current Jep instance

getLightWeightInstance

public JepComponent getLightWeightInstance()

Description copied from interface: JepComponent

Gets a light-weight instance suitable for using in multiple threads.

Specified by:

getLightWeightInstance in interface JepComponent

Returns:

either a new instance, null or 'this'.