org.jscience.physics.fluids.dynamics.util
Class EvaluateExpression

java.lang.Object
  java.io.StreamTokenizer
      org.jscience.physics.fluids.dynamics.util.EvaluateExpression

public class EvaluateExpression
extends java.io.StreamTokenizer

This class is used to interprete mathematical expressions. The code is mostly from the Aray v7.0 programed by myself. The possibilities of the interpreter are infinite, you can introduce new functions and interconect them with other parts of the program.

Field Summary

java.lang.String

VERSION version of the class

Fields inherited from class java.io.StreamTokenizer

nval, sval, TT_EOF, TT_EOL, TT_NUMBER, TT_WORD, ttype

Constructor Summary

EvaluateExpression(java.lang.String expression)
Constructor of the class.

Method Summary

void	assignsVariable(java.lang.String name, double value) Introduce a new variable in the list of variables of the user.
double	result() Returns the value of the expression.
double	result(double xv, double yv) Returns the result of a expression type F(x,y).
double	result(double xv, double yv, double zv) Returns the result of a expression type F(x,y,z).

Methods inherited from class java.io.StreamTokenizer

commentChar, eolIsSignificant, lineno, lowerCaseMode, nextToken, ordinaryChar, ordinaryChars, parseNumbers, pushBack, quoteChar, resetSyntax, slashSlashComments, slashStarComments, toString, whitespaceChars, wordChars

Methods inherited from class java.lang.Object

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

Field Detail

VERSION

public final java.lang.String VERSION

version of the class

See Also:

Constant Field Values

Constructor Detail

EvaluateExpression

public EvaluateExpression(java.lang.String expression)

Constructor of the class. Takes a argument the string that contains the mathematical formula to be evaluated.

Parameters:

expression -

Method Detail

assignsVariable

public void assignsVariable(java.lang.String name,
                            double value)

Introduce a new variable in the list of variables of the user.

Parameters:

name - string with the name of the variable.

value - numerical value to be assigned.

result

public double result()

Returns the value of the expression. The mathematical formula would have been passed to the constructor and the value of the variables would be definided in the function assignsVariable.

Returns:

DOCUMENT ME!

result

public double result(double xv,
                     double yv)

Returns the result of a expression type F(x,y). It is an abreviated form of invocation, as this method calls automatically assignsVariable for the indicated values of x and y.

Parameters:

xv - DOCUMENT ME!

yv - DOCUMENT ME!

Returns:

DOCUMENT ME!

result

public double result(double xv,
                     double yv,
                     double zv)

Returns the result of a expression type F(x,y,z). It is an abreviated form of invocation, as this method calls automatically assignsVariable for the indicated values of x and yz.

Parameters:

xv -

yv -

zv -

Returns: