What is a Pie Chart?

A pie graph (or pie chart) is a specialized graph used in statistics. The independent variable is plotted around a circle in either a clockwise direction or a counterclockwise direction. The dependent variable (usually a percentage) is rendered as an arc whose measure is proportional to the magnitude of the quantity. Each arc is depicted by constructing radial lines from its ends to the center of the circle, creating a wedge-shaped "slice." The independent variable can attain a finite number of discrete values (for example, five). The dependent variable can attain any value from zero to 100 percent. [from www.whatis.com]

The applet above creates a Pie chart based on integer inputs:

import java.applet.Applet; import java.awt.*; import java.awt.event.*; public class Pie extends Applet implements ActionListener { Label inputlabel; TextField input1, input2, input3, input4; Button b1; int number[], degrees[]; int sum, counter; public void init() { sum=0; counter=0; number=new int[4]; degrees=new int[4]; inputlabel= new Label("Enter four integers:"); input1=new TextField(5); input2=new TextField(5); input3=new TextField(5); input4=new TextField(5); b1=new Button("Draw Piechart"); add(inputlabel); add(input1); add(input2); add(input3); add(input4); add(b1); b1.addActionListener(this); } public void actionPerformed (ActionEvent e) { number[0]=Integer.parseInt (input1.getText()); number[1]=Integer.parseInt (input2.getText()); number[2]=Integer.parseInt (input3.getText()); number[3]=Integer.parseInt (input4.getText()); sum=number[0]+number[1] +number[2]+number[3]; degrees[0]=number[0]*360/sum; degrees[1]=number[1]*360/sum; degrees[2]=number[2]*360/sum; degrees[3]=360-degrees[0] -degrees[1]-degrees[2]; repaint(); } public void paint(Graphics g) { g.setColor(Color.red); g.fillArc (40,60,200,200,0,degrees[0]); g.setColor(Color.green); g.fillArc(40,60,200,200, degrees[0], degrees[1]); g.setColor(Color.blue); g.fillArc(40,60,200,200, degrees[0]+degrees[1], degrees[2]); g.setColor(Color.yellow); g.fillArc(40,60,200,200, degrees[0]+degrees[1]+degrees[2], degrees[3]); } }