import java.awt.*;import java.applet.*;import graph.*;public class parser extends Applet {    public static void main( String arg[] ) {        int l = arg.length;        double d;        if( l < 1 || l > 4 ) {          System.out.println(           "Usage: java parser \"function\" [x value] [y value] [z value]");          return;        }        System.out.println("Parse Function: "+arg[0]);        ParseFunction function = new ParseFunction(arg[0]);        if( l >= 2 ) {                      d = Double.valueOf(arg[1]).doubleValue();                      System.out.println("x = "+d);                      function.setX(d);        }        if( l >= 3 ) {                      d = Double.valueOf(arg[2]).doubleValue();                      System.out.println("y = "+d);                      function.setY(d);        }        if( l >= 4 ) {                      d = Double.valueOf(arg[3]).doubleValue();                      System.out.println("z = "+d);                      function.setZ(d);        }        function.debug = true;        if( !function.parse() ) {          System.out.println("Error: Failed to parse function");          return;        }        try {             System.out.println("Solution: "+function.getResult());        } catch(Exception e) {             e.printStackTrace();        }    }}