用Java绘制散点图
我遇到了这段代码,我一直在玩它,但是我试图绘制的点似乎在错误的地方。我希望能够像图形一样绘制,所以原点(0,0)应该在左下角,点应该相对于它绘制,可以帮助我吗用Java绘制散点图,java,graphics,Java,Graphics,我遇到了这段代码,我一直在玩它,但是我试图绘制的点似乎在错误的地方。我希望能够像图形一样绘制,所以原点(0,0)应该在左下角,点应该相对于它绘制,可以帮助我吗 package graphtest; import javax.swing.*; import java.awt.geom.*; import java.awt.Graphics; import java.util.*; public class Scatterplot extends javax.swing.JFrame {
package graphtest;
import javax.swing.*;
import java.awt.geom.*;
import java.awt.Graphics;
import java.util.*;
public class Scatterplot extends javax.swing.JFrame {
private List points = new ArrayList();
public Scatterplot() {
super("Scatterplot");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
points.add(new Point2D.Float(1, 4));
points.add(new Point2D.Float(2, 10));
points.add(new Point2D.Float(3, 12));
//points.add(new Point2D.Float(3, 10));
// points.add(new Point2D.Float(4, 12));
JPanel panel = new JPanel() {
public void paintComponent(Graphics g) {
//g.translate(0, 0);
for(Iterator i=points.iterator(); i.hasNext(); ) {
Point2D.Float pt = (Point2D.Float)i.next();
g.drawString(".", (int)pt.x, (int)pt.y);
}
}
};
setContentPane(panel);
setBounds(10, 10, 200, 200);
setVisible(true);
}
public static void main(String[] args) {
new Scatterplot();
}
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 400, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 300, Short.MAX_VALUE)
);
pack();
}// </editor-fold>
// Variables declaration - do not modify
// End of variables declaration
}
包装图测试;
导入javax.swing.*;
导入java.awt.geom.*;
导入java.awt.Graphics;
导入java.util.*;
公共类散点图扩展了javax.swing.JFrame{
私有列表点=新的ArrayList();
公共散点图(){
超级(“散点图”);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
添加(新的Point2D.Float(1,4));
添加(新的Point2D.Float(2,10));
添加(新的Point2D.Float(3,12));
//添加(新的Point2D.Float(3,10));
//添加(新的Point2D.Float(4,12));
JPanel panel=newjpanel(){
公共组件(图形g){
//g、 翻译(0,0);
for(迭代器i=points.Iterator();i.hasNext();){
Point2D.Float pt=(Point2D.Float)i.next();
g、 抽绳(“.”,(int)pt.x,(int)pt.y);
}
}
};
设置内容窗格(面板);
立根(10,10,200,200);
setVisible(真);
}
公共静态void main(字符串[]args){
新散点图();
}
//
私有组件(){
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
javax.swing.GroupLayout=newjavax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(布局);
layout.setHorizontalGroup(
createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0,400,短。最大值)
);
layout.setVerticalGroup(
createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0,300,短。最大值)
);
包装();
}//
//变量声明-不修改
//变量结束声明
}
您遇到的最大问题(除了不理解代码试图做什么之外)是
super.paintComponent
抽绳
drawString
绘制
字符意味着点将显示在指定的y
位置下方,因为字符必须考虑构成字体的所有字符的总高度。字体也呈现在上升线附近,这也会使y
位置关闭
相反,您应该更好地使用Graphics2D
API,并实际绘制圆点,例如
这个示例基本上使用了一个椭圆E2D
来绘制点,我已经设置好了它,这样它可以在指定的x/y坐标处绘制点的中心
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Scatterplot extends javax.swing.JFrame {
private List points = new ArrayList();
public Scatterplot() {
super("Scatterplot");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
points.add(new Point2D.Float(1, 4));
points.add(new Point2D.Float(2, 10));
points.add(new Point2D.Float(3, 12));
//points.add(new Point2D.Float(3, 10));
// points.add(new Point2D.Float(4, 12));
JPanel panel = new JPanel() {
@Override
public void paintComponent(Graphics g) {
//g.translate(0, 0);
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
// g.setColor(Color.RED);
// g.drawRect(0, 0, getWidth() - 1, getHeight() - 1);
g.setColor(Color.BLACK);
for (Iterator i = points.iterator(); i.hasNext();) {
Point2D.Float pt = (Point2D.Float) i.next();
Ellipse2D dot = new Ellipse2D.Float(pt.x - 1, pt.y - 1, 2, 2);
g2d.fill(dot);
}
g2d.dispose();
}
};
setContentPane(panel);
setBounds(10, 10, 200, 200);
setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
new Scatterplot();
}
});
}
}
查看更多详细信息在进行任何绘图之前,请确保您正在调用
super.paintComponent
。坐标将相对于绘制它们的组件,而不是框架。。。