用java语言绘制正弦曲线

用java语言绘制正弦曲线

很简单，程序写给你，给分：
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import java.awt.*;
import javax.swing.JFrame;
import java.util.Random;
import java.text.DecimalFormat;
public class SinDemo extends JFrame {
        private double cx = 1, cy = 1;
        private double toCx = 1, toCy = 1;
        private Random rnd = new Random();
        private DecimalFormat df = new DecimalFormat("0.00");
        private SinDemo () {
                super("Sin-Demo");
                setSize(600, 600);
                setLocationRelativeTo(null);
                setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                setVisible(true);
                run();
        }
        private int translateX (double x) {
                return (int)(x*getWidth()/Math.PI/4 + getWidth()/2);
        }
        private int translateY (double y) {
                return (int)(getHeight()/2 - y*getWidth()/Math.PI/4);
        }
        private double sin (double x) {
                return (cy * Math.sin(cx * x));
        }
        @Override
        public void paint (Graphics g) {
                super.paint(g);
                g.setColor(Color.BLUE);
                g.drawString("y = " + df.format(cx) + " * sin( " + df.format(cy) + " * x)", 50, 50);
                g.setColor(Color.LIGHT_GRAY);
                g.drawLine(0, getHeight()/2, getWidth(), getHeight()/2);
                g.drawLine(getWidth()/2, 0, getWidth()/2, getHeight());
                g.setColor(Color.BLACK);
                for (double i=-Math.PI/cx; i                        g.drawLine(translateX(i), translateY(sin(i)),
                                translateX(i+0.1), translateY(sin(i+0.1)));
        }
        public void run () {
                while (true) {
                        if (Math.abs(cx - toCx) < 0.1) {
                                toCx = rnd.nextDouble()*2;
                                toCy = rnd.nextDouble()*2;
                        }
                        cx += (toCx - cx)/50;
                        cy += (toCy - cy)/50;
                        paint(getGraphics());
                        try {
                                Thread.sleep(80);
                        } catch (InterruptedException ie) {}
                }
        }
        public static void main (String args[]) {
                new SinDemo();
        }
} 
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再给你一个截图：

你去找找thinking in java第四版
gui部分有一个话正弦曲线的，
而且可以有slider控制曲线变换