math.objects
Class Expression

java.lang.Object
  |
  +--math.objects.Expression

Direct Known Subclasses:

BinaryExpression, Constant, UnaryExpression, Variable

public abstract class Expression

extends java.lang.Object

The Expr class defines a binary node that contains a data element and a left child and right child each pointing to a expr class object

Since:

JDK1.1

Version:

1.0

Author:

Peter Staab

, Pete Fox , both for the Mathematical Visualization Project for the Department of Applied Mathematics, University of Colorado at Boulder

Constructor Summary

Expression()

Method Summary

abstract Expression	differentiate(Variable var) An abstract method that returns a Expression representation of the derivative of the current Expression.
double	evaluate() An abstract method used to evaluate a symbolic object given a nothing
double	evaluate(Variable var, double value) An abstract method used to evaulate a symbolic object given a one variable name and one value
double	evaluate(Variable var1, double value0, Variable var2, double value1) An abstract method used to evaluate a symbolic object given two variable names and two values
double	evaluate(Variable var1, double value0, Variable var2, double value1, Variable var3, double value2) A method used to evaluate a symbolic object given three variable names and three values
double	evaluate(Variable var1, double value1, Variable var2, double value2, Variable var3, double value3, Variable var4, double value4) A method used to evaluate a symbolic object given 4 variable names and 4 values
abstract double	evaluate(VariableSet variables, double[] values) A new abstract method used to evaulate a symbolic object given an ordered variable vector and a corresponding array of constant values
abstract Expression	evaluateVariables(VariableSet variables, double[] values) An abstract method used to evaluate a symbolic object containing multiple variables given only one variable name and one value
abstract Expression	simplify() An abstract method that returns a Expression representation of the the current Expression but in a simplified form with redundant terms eliminated.

Methods inherited from class java.lang.Object

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

Constructor Detail

Expression

public Expression()

Method Detail

evaluate

public double evaluate()
                throws java.lang.ArithmeticException,
                       VariableUndefinedException

An abstract method used to evaluate a symbolic object given a nothing

Returns:

a double representing the value of the Expression.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

VariableUndefinedException - for Variables not defined

Since:

JDK1.1

evaluate

public double evaluate(Variable var,
                       double value)
                throws java.lang.ArithmeticException,
                       VariableUndefinedException

An abstract method used to evaulate a symbolic object given a one variable name and one value

Parameters:

var - the name of the Variable associated with the function

value - the value of the Variable

Returns:

a double representing the value of the Expression for the entered value.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

VariableUndefinedException - for Variables not defined

Since:

JDK1.1

evaluate

public double evaluate(Variable var1,
                       double value0,
                       Variable var2,
                       double value1)
                throws java.lang.ArithmeticException,
                       VariableUndefinedException

An abstract method used to evaluate a symbolic object given two variable names and two values

Parameters:

var1 - the name of the first Variable associated with the function

value0 - a double value

var2 - the name of the second Variable associated with the function

value1 - the value of the first Variable

Returns:

a double representing the value of the Expression for the entered values.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

VariableUndefinedException - for Variables not defined

Since:

JDK1.1

evaluate

public double evaluate(Variable var1,
                       double value0,
                       Variable var2,
                       double value1,
                       Variable var3,
                       double value2)
                throws java.lang.ArithmeticException,
                       VariableUndefinedException

A method used to evaluate a symbolic object given three variable names and three values

Parameters:

var1 - the name of the first Variable associated with the function

value0 - a double value

var2 - the name of the second Variable associated with the function

value1 - the value of the first Variable

var3 - the name of the second Variable associated with the function

value2 - the value of the second Variable

Returns:

a double representing the value of the Expression for the entered values.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

VariableUndefinedException - for Variables not defined

Since:

JDK1.1

evaluate

public double evaluate(Variable var1,
                       double value1,
                       Variable var2,
                       double value2,
                       Variable var3,
                       double value3,
                       Variable var4,
                       double value4)
                throws java.lang.ArithmeticException,
                       VariableUndefinedException

A method used to evaluate a symbolic object given 4 variable names and 4 values

Parameters:

var1 - the name of the first Variable associated with the function

value1 - the value of the first Variable

var2 - the name of the second Variable associated with the function

value2 - the value of the second Variable

var3 - the name of the second Variable associated with the function

value3 - the value of the third Variable

Returns:

a double representing the value of the Expression for the entered values.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

VariableUndefinedException - for Variables not defined

evaluate

public abstract double evaluate(VariableSet variables,
                                double[] values)
                         throws java.lang.ArithmeticException,
                                IllegalEvaluationException,
                                VariableUndefinedException

A new abstract method used to evaulate a symbolic object given an ordered variable vector and a corresponding array of constant values

Parameters:

variables - a VariableSet value

Returns:

a double representing the value of the Expression for the entered value.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

IllegalEvaluationException - if an error occurs

VariableUndefinedException - for Variables not defined

Since:

JDK1.1

differentiate

public abstract Expression differentiate(Variable var)

An abstract method that returns a Expression representation of the derivative of the current Expression.

Parameters:

var - the variable of differentiation

Returns:

an Expression object representing the derivative of the current object

simplify

public abstract Expression simplify()

An abstract method that returns a Expression representation of the the current Expression but in a simplified form with redundant terms eliminated.

Returns:

an Expression object in a simplified form

evaluateVariables

public abstract Expression evaluateVariables(VariableSet variables,
                                             double[] values)
                                      throws java.lang.ArithmeticException,
                                             IllegalEvaluationException

An abstract method used to evaluate a symbolic object containing multiple variables given only one variable name and one value

Parameters:

variables - a VariableSet value

values - a double[] value

Returns:

a Expression object representing the given Expression with one of it's variables evaluated for the given value.

Throws:

java.lang.ArithmeticException - for NaN and Divide by Zero

IllegalEvaluationException - if an error occurs