分形和数据结构之迭代实现分形
迭代实现分形之一：
package 文雅0605;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
public class ring extends JFrame{
public static void main(String[] args) {
ring fl=new ring();
fl.initUI();
}
public void initUI(){
getContentPane().setBackground(Color.white);
setTitle("ring");
setSize(600,500);
setDefaultCloseOperation(3);
setLocationRelativeTo(null);
setLayout(new FlowLayout());
setVisible(true);
Graphics g = getGraphics();//注意这里一定要在窗体可见之后才能调用
((Graphics2D) g).setColor(Color.BLACK);
ringListener fl = new ringListener();
addMouseListener(fl);
fl.setGraphics(g);
}
}
package 文雅0605;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class ringListener implements MouseListener {
double x= 0, y = 0;
private Graphics g;
public Color color;
public int i;
public double x1, y1;
public void setGraphics(Graphics gra) {
g = (Graphics2D) gra;
}
public void mouseClicked(MouseEvent e) {
if(e.getClickCount()==2){//双击
double a = 1.40, b = 1.56, c = 1.40, d =-6.56;
for (int i = 0; i < 100000; i++) {
x1= d* Math.sin(a * x) - Math.sin(b * y);
y1= c* Math.cos(a * x) + Math.cos(b* y);
//int m = (int)(x1*10+200);
//int n = (int)(y1*10+200);
int m = (int) (x1* 20+300);
int n = (int) (y1* 20+300);//固定了图形的位置
//g.setColor(new Color(100, i %50 , i % 50));或者直接在窗体上((Graphics2D) g).setColor(Color.BLACK);设置颜色
g.drawLine(m,n,m,n);
//g.drawLine((int)x1*50+500,(int)y1*20+500,(int)x1*50+500,(int)y1*20+500);这种写法是错误的，图形的要求是要先算出结果再强制转型
x=x1;
y=y1;//迭代思维
}
x=0;
y=0;//能够控制绘制图形的新一轮的循环
}
else{
double a=-2,b=-2,c=-1.2,d=2;
for (int i = 0; i < 100000; i++) {
x1= (Math.sin(a * y) - Math.cos(b * x));
y1= (Math.sin(c * x) - Math.cos(d* y));
int m = (int) (x1* 50 +500);//乘数控制图形大小，加法控制图形的位置，但是范围要控制在第一象限，否则无法看到图形
int n = (int) (y1 *50 +500);
g.drawLine(m,n,m,n);
x=x1;
y=y1;
}
x=0;
y=0;
}
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public static void main(String[] args) {
}
}
输出结果：
：
迭代实现分形之二：
package 文雅0612;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
public class net extends JFrame {
public static void main(String[] args) {
net fl = new net();
fl.initUI();
}
public void initUI() {
getContentPane().setBackground(Color.black);
setTitle("net");
setSize(600, 500);
setDefaultCloseOperation(3);
setLocationRelativeTo(null);
setLayout(new FlowLayout());
setVisible(true);
Graphics g = getGraphics();
((Graphics2D) g).setColor(Color.BLUE);
netListener fl = new netListener();
addMouseListener(fl);
fl.setGraphics(g);
}
}
package 文雅0612;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class netListener implements MouseListener {
double x = 0, y = 0;
private Graphics g;
public int i;
public double x1, y1;
public void setGraphics(Graphics gra) {
g = (Graphics2D) gra;
}
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) {// 双击
for (int i = 0; i < 25000; i++) {
double a = 0.4, b = 1, c = 0;
// x1 = y - Math.signum(x) * Math.pow(Math.abs(b * x - c), 0.5);//到java目录中去寻找Math的应用，记得要在调用方法前面加上Math
x1 = y - Math.signum(x) * Math.sqrt(Math.abs(b * x - c));这两种方法都可以
y1 = a - x;
int m = (int) (x1 * 150 + 550);
int n = (int) (y1 * 150 + 550);
// System.out.println(m+" "+x); 追踪输出值，这是一个检验差错的好方法
g.drawLine(m, n, m, n);
x = x1;
y = y1;
}
x = 0;
y = 0;
} else {
for (int i = 0; i < 100000; i++) {
int a = 1, b = 4, c = 60;
// x1 = y - Math.signum(x) * Math.pow(Math.abs(b * x - c), 0.5);
x1 = y - Math.signum(x) * Math.sqrt(Math.abs(b * x - c));
y1 = a - x;
int m = (int) (x1 * 1 + 300);// 乘数控制图形大小，加法控制图形的位置
int n = (int) (y1 * 1+ 300);//该图形的乘数不能太大，最好控制在0-5之间
g.drawLine(m, n, m, n);
x = x1;
y = y1;
}
x = 0;
y = 0;
}
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public static void main(String[] args) {
}
}
输出结果：
感悟：刚开始的时候觉得很难，但是后来慢慢发现其实这种迭代分形应该是最容易的了。我们要注意的是把公式写对，用正确的方法去检验错误，问题基本上就迎刃而解了。通过这些分形的练习，我发现迭代分形的思路是这样的：首先，写完之后图形出不来一般是自己公式写错了，这个时候用System.out.println()去追踪代码输出的结果，从而找到自己出错的地方；接下来，如果图像不是自己想要的结果，则要注意你自己给图形扩大的程度了，也许是自己把图形放的太大了，也许是自己缩小了范围。
