?
Solved

Calling a graphing method

Posted on 2006-11-26
1
Medium Priority
?
279 Views
Last Modified: 2010-03-31
Assuming that i have the following code and it works to make just a basic graph show up without any graphing calculations yet....how do I call the graph from the MAIN METHOD to make it show up?

import java.util.Scanner;
import java.text.DecimalFormat;

public class Poly
{
     public static void main (String[] args)
          {
double c4,c3,c2,c1,c0,x,interval,xvalue;
int ptnumber,counter;
String result;

DecimalFormat fmt = new DecimalFormat ("0.##");

Scanner scan = new Scanner (System.in);

System.out.print ("Enter the coefficient of x^4(0.0 if none:");
c4 = scan.nextDouble();

System.out.print ("Enter the coefficient of x^3(0.0 if none:");
c3 = scan.nextDouble();

System.out.print ("Enter the coefficient of x^2(0.0 if none:");
c2 = scan.nextDouble();

System.out.print ("Enter the coefficient of x^1(0.0 if none:");
c1 = scan.nextDouble();

System.out.print ("Enter the constant:");
c0 = scan.nextDouble();

System.out.print ("Enter the starting value of x:");
x = scan.nextDouble();

System.out.print ("Enter the number of points to be graphed(Integer):");
ptnumber = scan.nextInt();

System.out.print ("Enter the interval between points:");
interval = scan.nextDouble();


Polynomial pn = new Polynomial(c4, c3, c2, c1, c0);

System.out.println("f(x)="+pn);

System.out.println("x     | f(x)");
System.out.println("----------");
counter = 0;
while (counter < ptnumber)
{

System.out.println(x          +"     | "+fmt.format(pn.evaluate(x)));

x = (x + interval);
counter++;
}

     }
}


POLY CLASS

import javax.swing.JPanel;
import java.awt.*;
import java.text.DecimalFormat;


import java.text.DecimalFormat;
public class Polynomial
{
   double coeff4, coeff3, coeff2, coeff1, constant;
     String sign4,sign3,sign2,sign1,sign0;
   public Polynomial(double c4, double c3, double c2, double c1, double c0)
     {
          coeff4 = c4;
          coeff3 = c3;
          coeff2 = c2;
          coeff1 = c1;
          constant = c0;
     
     }
     
     public double evaluate(double x)
     {
               
          double xsq = x*x;
         return (coeff4*xsq*xsq + coeff3*xsq*x + coeff2*xsq + coeff1*x + constant);
     
     }
     
     public String toString()

  {
        String result = "";

           if (coeff4 != 0)
        {
               result += coeff4+"x^4";
           }
          if (coeff3 != 0)
        {
            if (coeff3 > 0)
                result += "+";
             
               result += coeff3+"x^3";
           }
          if (coeff2 != 0)
        {
            if (coeff2 > 0)
                result += "+";
             
                result += coeff2+"x^2";
           }
           if (coeff1 != 0)
        {
            if (coeff1 > 0)
                result += "+";
             
               result += coeff1+"x";
           }
       if(constant!=0)
     {
      if(constant>0)
          result+="+";

         result += constant;
      }

          return result;
           
  }

     
  public void draw(Graphics page, int xPixels, int yPixels)
{
    final int NUM = 11;
    final double INTERVAL = 0.5;
    final double XSTART = 0.0;

    final int XMARGIN = 70;
    final int XUSABLEPIXELS = xPixels - 2*XMARGIN;
    final int XINTERVALPIXELS = XUSABLEPIXELS/(NUM - 1);
    final int YMARGIN =40;
    final int YUSABLEPIXELS = yPixels - 2*YMARGIN;
     
       // Label the graph
    page.drawString("Graph of f(x) = " + toString(), XMARGIN + 20, YMARGIN);

    // Draw the x axis and put in hash marks
    page.drawLine(XMARGIN, yPixels - YMARGIN, xPixels - XMARGIN, yPixels - YMARGIN);
    for ( int i = 0; i < NUM; i++ )
        page.drawLine(XMARGIN + i * XINTERVALPIXELS, yPixels - YMARGIN, XMARGIN + i * XINTERVALPIXELS, yPixels - YMARGIN + 5);
           
      DecimalFormat twoPlaces = new DecimalFormat("0.00");

    // Label the x axis
    for (int i = 0; i < NUM; i++)
    {
        page.drawString( twoPlaces.format(XSTART + i * INTERVAL), 3 * XMARGIN / 4 + i * XINTERVALPIXELS, yPixels - YMARGIN/2);
    }

    // Draw the y axis
    page.drawLine(XMARGIN, YMARGIN, XMARGIN, yPixels - YMARGIN);

    // Label the y axis and put in hash marks
    final double YMIN = 0.0;
    final double YINTERVAL = 100.0;
    final int YINTERVALPIXELS = YUSABLEPIXELS / 10;

    for (int i = 0; i < NUM; i++)
    {
        page.drawString(twoPlaces.format(YMIN + i * YINTERVAL), XMARGIN / 4, yPixels - i * YINTERVALPIXELS - YMARGIN);
        page.drawLine(XMARGIN, yPixels - YMARGIN - i * YINTERVALPIXELS, XMARGIN - 5, yPixels - YMARGIN - i * YINTERVALPIXELS);
    }

   
   }
}


           

0
Comment
Question by:lusius188
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
1 Comment
 
LVL 10

Accepted Solution

by:
ADSLMark earned 750 total points
ID: 18013935
You have to create a class which extends from JFrame. You create an instance of this class in your main method. Next you add an extension of a JPanel with the graph drawing code to the frame and voila.

sth like:

import javax.swing.*;
class MyGraphExample extends JFrame
{
    public MyGraphExample()
    {
        this.setTitle("My graph");
        this.setSize(800,600);
        this.setLayout(new BorderLayout());
        this.add(new MyGraphPanel(), BorderLayout.CENTER);
    }
    public static void main(String[] args)
    {
        MyGraphExample mge = new MyGraphExample();
        mge.setVisible(true);
    }
}

import javax.swing.*;
class MyGraphPanel extends JPanel
{
    public MyGraphPanel()
    {
    }

    public void paintComponent(Graphics g)
    {
        ... perform drawing here ...
    }
}

Good luck.
Mark
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

INTRODUCTION Working with files is a moderately common task in Java.  For most projects hard coding the file names, using parameters in configuration files, or using command-line arguments is sufficient.   However, when your application has vi…
Java Flight Recorder and Java Mission Control together create a complete tool chain to continuously collect low level and detailed runtime information enabling after-the-fact incident analysis. Java Flight Recorder is a profiling and event collectio…
This tutorial covers a step-by-step guide to install VisualVM launcher in eclipse.
This tutorial explains how to use the VisualVM tool for the Java platform application. This video goes into detail on the Threads, Sampler, and Profiler tabs.
Suggested Courses
Course of the Month10 days, 3 hours left to enroll

762 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question