import java.awt.*;import java.applet.*;import java.net.URL;import java.util.*;import graph.*;/*****************************************************************************    Applet example6**                                              Version 1.0   February 1996******************************************************************************    Copyright (C) 1996 Leigh Brookshaw****    This program is free software; you can redistribute it and/or modify**    it under the terms of the GNU General Public License as published by**    the Free Software Foundation; either version 2 of the License, or**    (at your option) any later version.****    This program is distributed in the hope that it will be useful,**    but WITHOUT ANY WARRANTY; without even the implied warranty of**    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the**    GNU General Public License for more details.****    You should have received a copy of the GNU General Public License**    along with this program; if not, write to the Free Software**    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.******************************************************************************    This applet demonstrates the the contouring cababilities**    of the Contour class***************************************************************************/public class example6 extends Applet {      LoadData dynamic;      Contour graph;      Label title;      Axis    xaxis;      Axis    yaxis;      public void init() {        int i;        int j;/***      Instantiate the Contour class and calculate the data*/        graph = new Contour();        graph.setDataBackground(new Color(0.933f,0.914f,0.749f));        graph.setContourColor(new Color(0.180f,0.545f,0.341f));        graph.setLabelledContourColor(new Color(0.5f,.0f,0.0f));        graph.setLabelPrecision(2);        graph.setLabelSignificance(2);        this.showStatus("Creating Data to Contour!");        createGrid(graph);        graph.square       = true;/***      Build the title and place it at the top of the graph*/        graph.setFont(new Font("TimesRoman",Font.PLAIN,25));        title = new Label("Contouring Example", Label.CENTER);        title.setFont(new Font("TimesRoman",Font.PLAIN,25));        setLayout( new BorderLayout() );        add("North",  title);        add("Center", graph);/***      Instantiate the xaxis and attach the dataset.*/        xaxis = graph.createXAxis();        xaxis.setTitleText("X_axis");        xaxis.setTitleColor(Color.magenta);        xaxis.setTitleFont(new Font("TimesRoman",Font.ITALIC,25));        xaxis.setLabelFont(new Font("Helvetica",Font.PLAIN,20));/***      Instantiate the yaxis and attach the dataset.*/        yaxis = graph.createYAxis();        yaxis.setTitleText("Y_axis");        yaxis.setTitleColor(Color.magenta);         yaxis.setTitleFont(new Font("TimesRoman",Font.ITALIC,25));        yaxis.setLabelFont(new Font("Helvetica",Font.PLAIN,20));      }      public void createGrid(Contour graph) {         int i,j;         int count;                  int nx = 50;         int ny = 50;         double xmin = -1.0;         double xmax =  1.0;         double ymax =  1.0;         double ymin = -1.0;         double array[] = new double[nx*ny];         double x, y, rad;         double h1, h2, h3;         h1 = 0.5*0.5;         h2 = 0.75*0.75;         h3 = 0.25*0.25;         count = 0;         for(j=0; j<ny; j++) {             y = 2.0*(double)j/(double)(ny-1) - 1.0;             for(i=0; i<nx; i++) {                x = 2.0*(double)i/(double)(nx-1) - 1.0;                rad = (x-0.5)*(x-0.5) + (y+0.5)*(y+0.5);                array[count] = Math.exp( -rad/h1 );                rad = (x+0.3)*(x+0.3) + (y-0.75)*(y-0.75);                array[count] += Math.exp( -rad/h2 );                rad = (x+0.7)*(x+0.7) + (y+0.6)*(y+0.6);                array[count] += Math.exp( -rad/h3 );                count++;  	      }	   }           graph.setGrid(array,nx,ny);           graph.setRange(xmin,xmax,ymin,ymax);           graph.setLimitsToGrid(true);           graph.setLabelLevels(3);           graph.setNLevels(20);      }}