Package org.opensourcephysics.tools

Class UserFunction

java.lang.Object

org.opensourcephysics.tools.UserFunction

All Implemented Interfaces:

java.lang.Cloneable, Function, MultiVarFunction, KnownFunction

public class UserFunction
extends java.lang.Object
implements KnownFunction, MultiVarFunction, java.lang.Cloneable

A known function for which the expression and parameters are user-editable.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	UserFunction.Loader	A class to save and load UserFunction data in an XMLControl.

Field Summary

Fields

Modifier and Type	Field	Description
protected java.lang.String	description
protected static java.lang.String[]	dummyVars
protected java.lang.String	expression
protected ParsedMultiVarFunction	function
protected java.lang.String[]	functionNames
protected java.lang.String	inputString
protected java.lang.String	name
protected boolean	nameEditable
protected java.lang.String[]	paramDescriptions
protected java.lang.String[]	paramNames
protected double[]	paramValues
protected KnownPolynomial	polynomial
protected UserFunction[]	references
protected java.lang.String[]	vars

Constructor Summary

Constructors

Constructor	Description
UserFunction(java.lang.String name)	Constructor.
UserFunction(KnownPolynomial poly)	Constructor that copies a KnownPolynomial.

Method Summary

Modifier and Type	Method	Description
UserFunction	clone()	Returns a clone of this UserFunction.
boolean	equals(java.lang.Object f)	Determines if another KnownFunction is the same as this one.
double	evaluate(double x)	Evaluates the function for a single variable x.
double	evaluate(double[] x)	Evaluates the function for a variables array x.
boolean	evaluatedToNaN()	Determines if last evaluation resulted in NaN.
protected double[]	evaluateSupportFunctions(double x)	Evaluates the support functions for a single variable x.
protected double[]	evaluateSupportFunctions(double[] x)	Evaluates the support functions for a variables array x.
java.lang.String	getDescription()	Gets the description of this function.
java.lang.String	getExpression()	Gets the expression using the current variables.
java.lang.String	getExpression(java.lang.String indepVarName)	Gets the expression and sets the independent variable.
java.lang.String	getExpression(java.lang.String[] varNames)	Gets the expression and sets the independent variables.
java.lang.String	getFullExpression(java.lang.String[] varNames)	Gets the full expression using the current variables.
java.lang.String[]	getFunctionNames()	Returns function names.
java.lang.String	getIndependentVariable()	Gets the current independent variable.
java.lang.String[]	getIndependentVariables()	Gets the current independent variables.
java.lang.String	getInputString()	Gets the expression.
static XML.ObjectLoader	getLoader()	Returns the XML.ObjectLoader for this class.
java.lang.String	getName()	Gets the name.
int	getParameterCount()	Gets the parameter count.
java.lang.String	getParameterDescription(int i)	Gets a parameter description.
java.lang.String	getParameterName(int i)	Gets a parameter name.
double	getParameterValue(int i)	Gets a parameter value.
boolean	isNameEditable()	Returns true if the name is user-editable.
protected java.lang.String	replaceParameterNameInExpression(java.lang.String oldName, java.lang.String newName)	Replaces a parameter name with a new one in the function expression.
void	setDescription(java.lang.String desc)	Sets the description of this function.
boolean	setExpression(java.lang.String exp, java.lang.String[] varNames)	Sets the expression.
void	setName(java.lang.String name)	Sets the name.
void	setNameEditable(boolean editable)	Sets the name editable property.
void	setParameters(java.lang.String[] names, double[] values)	Sets the parameters.
void	setParameters(java.lang.String[] names, double[] values, java.lang.String[] descriptions)	Sets the parameters.
void	setParameterValue(int i, double value)	Sets a parameter value.
void	setReferences(UserFunction[] functions)	Sets the reference functions.
boolean	updatePolynomial()	Updates the associated polynomial, if any, with this functions current properties.
void	updateReferenceParameters()	Sets the parameters of reference functions to those of this function.

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

dummyVars

protected static java.lang.String[] dummyVars

name

protected java.lang.String name

paramNames

protected java.lang.String[] paramNames

paramValues

protected double[] paramValues

paramDescriptions

protected java.lang.String[] paramDescriptions

functionNames

protected java.lang.String[] functionNames

expression

protected java.lang.String expression

inputString

protected java.lang.String inputString

function

protected ParsedMultiVarFunction function

vars

protected java.lang.String[] vars

references

protected UserFunction[] references

nameEditable

protected boolean nameEditable

description

protected java.lang.String description

polynomial

protected KnownPolynomial polynomial

Constructor Detail

UserFunction

public UserFunction(java.lang.String name)

Constructor.

Parameters:

name - the function name

UserFunction

public UserFunction(KnownPolynomial poly)

Constructor that copies a KnownPolynomial.

Parameters:

poly - the KnownPolynomial

Method Detail

getName

public java.lang.String getName()

Gets the name.

Specified by:

getName in interface KnownFunction

Returns:

the name

setName

public void setName(java.lang.String name)

Sets the name.

Specified by:

setName in interface KnownFunction

Parameters:

name - the name

isNameEditable

public boolean isNameEditable()

Returns true if the name is user-editable.

Returns:

true if editable

setNameEditable

public void setNameEditable(boolean editable)

Sets the name editable property.

Parameters:

editable - true if editable

getIndependentVariable

public java.lang.String getIndependentVariable()

Gets the current independent variable.

Returns:

the variable name

getIndependentVariables

public java.lang.String[] getIndependentVariables()

Gets the current independent variables.

Returns:

the variable names

getInputString

public java.lang.String getInputString()

Gets the expression.

Returns:

the expression

getExpression

public java.lang.String getExpression()

Gets the expression using the current variables.

Returns:

the expression

getExpression

public java.lang.String getExpression(java.lang.String indepVarName)

Gets the expression and sets the independent variable.

Specified by:

getExpression in interface KnownFunction

Parameters:

indepVarName - the name of the independent variable

Returns:

the expression

getExpression

public java.lang.String getExpression(java.lang.String[] varNames)

Gets the expression and sets the independent variables.

Parameters:

varNames - the name of the independent variables

Returns:

the expression

getFullExpression

public java.lang.String getFullExpression(java.lang.String[] varNames)

Gets the full expression using the current variables.

Parameters:

varNames - the name of the independent variables

Returns:

the expression

setExpression

public boolean setExpression(java.lang.String exp,
                             java.lang.String[] varNames)

Sets the expression.

Parameters:

exp - a parsable expression of the parameters and variables

varNames - the names of the independent variables

Returns:

true if successfully parsed

getParameterCount

public int getParameterCount()

Gets the parameter count.

Specified by:

getParameterCount in interface KnownFunction

Returns:

the number of parameters

getParameterName

public java.lang.String getParameterName(int i)

Gets a parameter name.

Specified by:

getParameterName in interface KnownFunction

Parameters:

i - the parameter index

Returns:

the name of the parameter

getParameterValue

public double getParameterValue(int i)

Gets a parameter value.

Specified by:

getParameterValue in interface KnownFunction

Parameters:

i - the parameter index

Returns:

the value of the parameter

setParameterValue

public void setParameterValue(int i,
                              double value)

Sets a parameter value.

Specified by:

setParameterValue in interface KnownFunction

Parameters:

i - the parameter index

value - the value

setParameters

public void setParameters(java.lang.String[] names,
                          double[] values)

Sets the parameters.

Parameters:

names - the parameter names

values - the parameter values

setParameters

public void setParameters(java.lang.String[] names,
                          double[] values,
                          java.lang.String[] descriptions)

Sets the parameters.

Specified by:

setParameters in interface KnownFunction

Parameters:

names - the parameter names

values - the parameter values

descriptions - the parameter descriptions

updateReferenceParameters

public void updateReferenceParameters()

Sets the parameters of reference functions to those of this function.

setReferences

public void setReferences(UserFunction[] functions)

Sets the reference functions.

Parameters:

functions - the functions referenced by this one

getDescription

public java.lang.String getDescription()

Gets the description of this function. May return null.

Specified by:

getDescription in interface KnownFunction

Returns:

the description

setDescription

public void setDescription(java.lang.String desc)

Sets the description of this function.

Specified by:

setDescription in interface KnownFunction

Parameters:

desc - the description

getParameterDescription

public java.lang.String getParameterDescription(int i)

Gets a parameter description. May be null.

Specified by:

getParameterDescription in interface KnownFunction

Parameters:

i - the parameter index

Returns:

the description of the parameter (may be null)

getFunctionNames

public java.lang.String[] getFunctionNames()

Returns function names. Added by D. Brown 10 Dec 2015

Returns:

array of parser function names

evaluate

public double evaluate(double x)

Evaluates the function for a single variable x.

Specified by:

evaluate in interface Function

Parameters:

x -

Returns:

f(x)

evaluate

public double evaluate(double[] x)

Evaluates the function for a variables array x.

Specified by:

evaluate in interface MultiVarFunction

Parameters:

x -

Returns:

f(x)

evaluatedToNaN

public boolean evaluatedToNaN()

Determines if last evaluation resulted in NaN.

Returns:

true if result was converted from NaN to zero

clone

public UserFunction clone()

Returns a clone of this UserFunction.

Specified by:

clone in interface KnownFunction

Overrides:

clone in class java.lang.Object

Returns:

the clone

equals

public boolean equals(java.lang.Object f)

Determines if another KnownFunction is the same as this one.

Specified by:

equals in interface KnownFunction

Overrides:

equals in class java.lang.Object

Parameters:

f - the KnownFunction to test

Returns:

true if equal

updatePolynomial

public boolean updatePolynomial()

Updates the associated polynomial, if any, with this functions current properties.

Returns:

true if updated

replaceParameterNameInExpression

protected java.lang.String replaceParameterNameInExpression(java.lang.String oldName,
                                                            java.lang.String newName)

Replaces a parameter name with a new one in the function expression.

Parameters:

oldName - the existing parameter name

newName - the new parameter name

Returns:

the modified expression, or null if failed

evaluateSupportFunctions

protected double[] evaluateSupportFunctions(double x)

Evaluates the support functions for a single variable x.

Parameters:

x -

Returns:

double[] of values

evaluateSupportFunctions

protected double[] evaluateSupportFunctions(double[] x)

Evaluates the support functions for a variables array x.

Parameters:

x -

Returns:

double[] of values

getLoader

public static XML.ObjectLoader getLoader()

Returns the XML.ObjectLoader for this class.

Returns:

the object loader