java画极坐标的库 java建立坐标系

 

import java.awt.*;
import javax.swing.*;

public class NumberAxis extends JPanel{
	JFrame frame;

	public static void main(String[] args) {
		NumberAxis numberAxis = new NumberAxis();
		numberAxis.go();
	}

	private void go() {
		frame = new JFrame();
		NumberAxis numberAxis = new NumberAxis();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setSize(500, 500);
		frame.add(numberAxis);
		frame.setTitle("刘佩伦的智障平面直角坐标系(y = " + "x * x * x" + ")");
		frame.setVisible(true);
	}

	@Override
	public void paintComponent(Graphics g) {
		g.setColor(Color.black);
		int height = this.getHeight();
		int width = this.getWidth();
		g.drawLine(0, height / 2, width, height / 2);
		g.drawLine(width / 2, 0, width / 2, height);
		//在屏幕中间构建平面直角坐标系
		double x, y;
		g.setColor(Color.blue);
		for (int i = 0; i < width; i++) {
			for (int j = 0; j < height; j++) {
				//遍历平面直角坐标系,如果一个点满足要求就绘制这个点
				x = (i - width / 2 - 1) / 100.0;
				y = (height / 2 - j - 1) / 100.0;
				if (isRight(y, x * x * x, 0.02)) {
					g.fillOval(i, j, 2, 2);
				}
			}
		}
	}
	
	boolean isRight(double num1, double num2, double error) {
		//判断两个数字是否在误差允许范围
		if (Math.abs(num1 - num2) <= error)
			return true;
			return false;
	}
}