com.singularsys.extensions.djep

Class PartialDerivative

java.lang.Object

java.util.Observable

com.singularsys.jep.Variable

com.singularsys.extensions.xjep.XVariable

com.singularsys.extensions.djep.DVariable

com.singularsys.extensions.djep.PartialDerivative

All Implemented Interfaces:

java.io.Serializable, java.util.Observer

public class PartialDerivative
extends DVariable
implements java.util.Observer

Contains information about a PartialDerivative of a variable.

Author:

Rich Morris Created on 29-Oct-2003

See Also:

Serialized Form

Field Summary

Fields inherited from class com.singularsys.extensions.djep.DVariable

derivatives

Fields inherited from class com.singularsys.jep.Variable

keys, keyVals, name

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PartialDerivative(DVariable var, java.lang.String[] derivnames) Protected constructor, should only be constructed through the findDerivative method in DVariable.
protected	PartialDerivative(DVariable var, java.lang.String[] derivnames, Node deriv)

Method Summary

Modifier and Type	Method and Description
boolean	derivativeIsTrivallyZero()
PartialDerivative	findDerivative(java.lang.String dname, DJep jep)
java.lang.String[]	getDnames()
java.lang.String	getName() Returns the variable name.
DVariable	getRoot() Every partial derivative has a root variable for instance the root variable of dy/dx is y.
java.lang.String	toString() Returns a string rep of variable with its equation and value.
void	update(java.util.Observable arg0, java.lang.Object arg1) When the value of the root object is changed makes the value of this partial derivative invalid.

Methods inherited from class com.singularsys.extensions.djep.DVariable

allDerivatives, calculateDerivative, createDerivative, invalidateAll, makeDerivString, setEquation, toString

Methods inherited from class com.singularsys.extensions.xjep.XVariable

calcValue, getEquation, hasEquation

Methods inherited from class com.singularsys.jep.Variable

getHook, getValue, hasValidValue, hookKeys, isConstant, removeHook, setHook, setIsConstant, setValidValue, setValue, setValue, setValueRaw

Methods inherited from class java.util.Observable

addObserver, clearChanged, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers, setChanged

Methods inherited from class java.lang.Object

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

Constructor Detail

PartialDerivative

protected PartialDerivative(DVariable var,
                            java.lang.String[] derivnames)

Protected constructor, should only be constructed through the findDerivative method in DVariable.

PartialDerivative

protected PartialDerivative(DVariable var,
                            java.lang.String[] derivnames,
                            Node deriv)

Method Detail

getName

public java.lang.String getName()

Description copied from class: Variable

Returns the variable name.

Overrides:

getName in class Variable

Returns:

the variable name.

getRoot

public DVariable getRoot()

Every partial derivative has a root variable for instance the root variable of dy/dx is y. This method returns than variable.

getDnames

public java.lang.String[] getDnames()

toString

public java.lang.String toString()

Description copied from class: XVariable

Returns a string rep of variable with its equation and value.

Overrides:

toString in class XVariable

Returns:

A string with the variable name and value.

findDerivative

public PartialDerivative findDerivative(java.lang.String dname,
                                        DJep jep)
                                 throws ParseException

Throws:

ParseException

update

public void update(java.util.Observable arg0,
                   java.lang.Object arg1)

When the value of the root object is changed makes the value of this partial derivative invalid.

Specified by:

update in interface java.util.Observer

See Also:

Observer.update(java.util.Observable, java.lang.Object)

derivativeIsTrivallyZero

public boolean derivativeIsTrivallyZero()

Overrides:

derivativeIsTrivallyZero in class DVariable