genopt.algorithm.util.math

Class FunctionEvaluator

java.lang.Object

genopt.algorithm.util.math.FunctionEvaluator

public class FunctionEvaluator
extends java.lang.Object

Function parser. This class parses a given String argument and computes the function value as specified by the String. To invoke the function, the class genopt.algorithm.util.math.Fun is parsed. If the function cannot be found in this class, then the class java.lang.StrictMath is parsed. A typical argment has the form add(2, subtract(sin(3), 1)).

This project was carried out at:

• Lawrence Berkeley National Laboratory (LBNL), Simulation Research Group,

and supported by

• the U.S. Department of Energy (DOE),
• the Swiss Academy of Engineering Sciences (SATW),
• the Swiss National Energy Fund (NEFF), and
• the Swiss National Science Foundation (SNSF)

GenOpt Copyright (c) 1998-2021, The Regents of the University of California, through Lawrence Berkeley National Laboratory (subject to receipt of any required approvals from the U.S. Dept. of Energy). All rights reserved.

Version:

GenOpt(R) 3.1.1 (March 24, 2016)

Author:

Michael Wetter

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private class	FunctionEvaluator.Element Internal class for an element that contains either a String, a double, or a char value.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.ArrayList<FunctionEvaluator.Element>	arrLis List with Elements that resulted from function parsing.
protected java.lang.String	Func Function to be evaluated.
private static java.lang.String	LS Line separator
protected java.lang.String	Name Function name.

Constructor Summary

Constructors

Constructor and Description
FunctionEvaluator(java.lang.String name, java.lang.String function) Creates a new FunctionEvaluator instance.

Method Summary

Modifier and Type	Method and Description
private FunctionEvaluator.Element	_evaluate(java.lang.String fun, java.util.Stack<java.lang.Double> sta) Evaluates the function fun using all elements in sta as the argument.
private java.lang.String	_getErrorMessagePrefix() Gets the prefix for the error message.
private FunctionEvaluator.Element	_parse(java.util.ArrayList<FunctionEvaluator.Element> lis, java.lang.String fun) Parses the function.
private void	_setArrayList() Sets the array list that will be used to evaluate the function
double	evaluate() Evaluates the function.
java.lang.String	getFunction()
java.lang.String	getName()

Methods inherited from class java.lang.Object

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

Field Detail

LS

private static final java.lang.String LS

Line separator

Name

protected java.lang.String Name

Function name.

Func

protected java.lang.String Func

Function to be evaluated.

arrLis

protected java.util.ArrayList<FunctionEvaluator.Element> arrLis

List with Elements that resulted from function parsing.

Constructor Detail

FunctionEvaluator

public FunctionEvaluator(java.lang.String name,
                         java.lang.String function)

Creates a new FunctionEvaluator instance.

Parameters:

name - name of the function

function - function to be evaluated

Method Detail

evaluate

public double evaluate()
                throws java.lang.NoSuchMethodException,
                       java.lang.IllegalAccessException,
                       java.lang.reflect.InvocationTargetException

Evaluates the function.

Returns:

the function value

Throws:

java.lang.NoSuchMethodException - if the method could not be found

java.lang.IllegalAccessException - if an error occurs

java.lang.reflect.InvocationTargetException - if an error occurs

java.lang.IndexOutOfBoundsException - if an error occurs

_setArrayList

private void _setArrayList()

Sets the array list that will be used to evaluate the function

_getErrorMessagePrefix

private java.lang.String _getErrorMessagePrefix()

Gets the prefix for the error message.

Returns:

the prefix for the error message

_parse

private FunctionEvaluator.Element _parse(java.util.ArrayList<FunctionEvaluator.Element> lis,
                                         java.lang.String fun)
                                  throws java.lang.NoSuchMethodException,
                                         java.lang.IllegalAccessException,
                                         java.lang.reflect.InvocationTargetException

Parses the function.

Parameters:

lis - the ArrayList with the function being evaluated. The function name must be passed in the fun argument.

fun - name of the function that has to be invoked

Returns:

an Element containing the function value

Throws:

java.lang.NoSuchMethodException - if an error occurs

java.lang.IllegalAccessException - if an error occurs

java.lang.reflect.InvocationTargetException - if an error occurs

_evaluate

private FunctionEvaluator.Element _evaluate(java.lang.String fun,
                                            java.util.Stack<java.lang.Double> sta)
                                     throws java.lang.NoSuchMethodException,
                                            java.lang.IllegalAccessException,
                                            java.lang.reflect.InvocationTargetException

Evaluates the function fun using all elements in sta as the argument.

Parameters:

fun - the name of the function that will be invoked

sta - a stack of Doubles that are the arguments of fun

Returns:

an Element that contains the function value

Throws:

java.lang.NoSuchMethodException - if an error occurs

java.lang.IllegalAccessException - if an error occurs

java.lang.reflect.InvocationTargetException - if an error occurs

getName

public java.lang.String getName()

getFunction

public java.lang.String getFunction()