applet1.java

阿基米德螺线 一种数学曲线

import java.awt.*;
import java.applet.*;
import java.awt.event.*;

public class Applet1 extends Applet implements ActionListener
	
{
	Label prompt;
	TextField inputx,inputy,inputa;
	Button OK;
	
	public void init()
	{
		prompt=new Label("请输入中心坐标及参数(x=400,y=200,a=3.4)a：");
		inputx=new TextField(5);
		inputy=new TextField(5);
		inputa=new TextField(5);
		OK=new Button("完成");
		
		add(prompt);
		add(inputx);
		add(inputy);
		add(inputa);
		add(OK);
		
		OK.addActionListener(this);

		
		
		
	}
	public void paint(Graphics g)
	{
		int x=Integer.parseInt(inputx.getText());
		int y=Integer.parseInt(inputy.getText());
		double a=Double.valueOf(inputa.getText()).doubleValue();
		
		for(double u=0;u<850;u+=0.005)
		{
			g.drawString(".",x,(int)u); 
			g.drawString(".",(int)u,y);
		}
		for(double i=0.1;i<9*6.28;i+=0.00005)
		{
			g.drawString(".",(int)(x+(a*i)*Math.cos(i)),(int)(y+(a*i)*Math.sin(i)));
		   
		}

		
		
	}
	public void actionPerformed(ActionEvent e)
	{

		repaint();
	}
}