org.lsmp.djep.xjep

Class CommandVisitor

java.lang.Object

org.lsmp.djep.xjep.DoNothingVisitor

org.lsmp.djep.xjep.CommandVisitor

All Implemented Interfaces:

ParserVisitor

public class CommandVisitor
extends DoNothingVisitor

Executes commands like diff and eval embedded in expression trees. For example you could do

eval(diff(x^3,x),x,2)

to differentiate x^3 and then substitute x=2 to get the value 12. To use do

 JEP j = ...; Node in = ...;
 TreeUtils tu = new TreeUtils(j);
 CommandVisitor cv = new CommandVisitor(tu);
 Node out = cv.process(in);
 

Commands to be executed must implement CommandVisitorI and PostfixMathCommandI. See Eval for an example of this. See ParserVisitor for details on the VisitorPattern.

Author:

R Morris Created on 19-Jun-2003

Constructor Summary

Constructors

Constructor and Description
CommandVisitor() private default constructor to prevent init without a tree utils

Method Summary

Methods

Modifier and Type	Method and Description
Node	process(Node node, XJep xj) Descends the tree processing all diff, eval and simplify options
java.lang.Object	visit(ASTFunNode node, java.lang.Object data)

Methods inherited from class org.lsmp.djep.xjep.DoNothingVisitor

acceptChildrenAsArray, visit, visit, visit, visit

Methods inherited from class java.lang.Object

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

Constructor Detail

CommandVisitor

public CommandVisitor()

private default constructor to prevent init without a tree utils

Method Detail

process

public Node process(Node node,
           XJep xj)
             throws ParseException

Descends the tree processing all diff, eval and simplify options

Throws:

ParseException

visit

public java.lang.Object visit(ASTFunNode node,
                     java.lang.Object data)
                       throws ParseException

Specified by:

visit in interface ParserVisitor

Overrides:

visit in class DoNothingVisitor

Throws:

ParseException