Looping help needed for math calculation
The monthly payment only returns "NaN" and the amortization does not display at all. I'm pretty sure my problem lies in my looping but i'm lost and unable to find it. HELP!!!!!
Code Java:
import java.awt.*;
import java.awt.event.*;
import java.math.*;
import java.text.*;
import java.lang.*;
import java.util.Locale;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
import javax.swing.JOptionPane;
public class Mortgage3 extends JFrame implements ActionListener {
double principal = 0; //principal
int length = 0; //years
int months = 0; //months
double interestRate = 0; //interest rate
double monthlyInterest = 0; //monthly interest rate
double monthlyPayment = 0; //monthly payment
double premium = 0; //premium
double interestPaid = 0; //interest paid
double balance = principal; //balance
DecimalFormat money = new DecimalFormat("$0.00"); //formats to 2 decimal places
JPanel row1 = new JPanel();
JLabel mortgage_label = new JLabel("Pam's Mortgage Calculator", JLabel.CENTER);
JPanel row2 = new JPanel(new GridLayout(1, 2));
JLabel principal_label = new JLabel("Enter Mortgage Amount (do not enter $ or cents):",JLabel.LEFT);
JTextField principal_txt = new JTextField(10);
JPanel row3 = new JPanel(new GridLayout(1, 2));
JLabel button_label = new JLabel("Please select one of the following options:", JLabel.CENTER);
JPanel row4 = new JPanel(new GridLayout(1, 3));
JRadioButton oneButton = new JRadioButton("7 years at 5.35%",true); //creates buttons
JRadioButton twoButton = new JRadioButton("15 years at 5.5%");
JRadioButton threeButton = new JRadioButton("30 years at 5.75%");
JPanel row5 = new JPanel(new GridLayout(1, 2));
JLabel monthlyPayment_label = new JLabel("Your monthly payment will be:", JLabel.LEFT);
JTextField monthlyPayment_txt = new JTextField(10);
JPanel row6 = new JPanel(new GridLayout(1, 2));
JButton resetButton = new JButton("Reset");
JButton exitButton = new JButton("Exit");
JButton calculateButton = new JButton("Calculate Monthly Payment");
JButton amortizationButton = new JButton("Show Amortization");
JTextArea displayArea = new JTextArea(10, 45); //for amortization display
JTextField number_txt = new JTextField(4);
JTextField balance_txt = new JTextField(12);
JTextField interestPaid_txt = new JTextField(12);
JScrollPane scroll = new JScrollPane(displayArea);
public Mortgage3() {
super ("Pam's Mortgage Calculator");
setSize(750, 600); //sets overall GUI size
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container pane = getContentPane();
Border rowborder = new EmptyBorder( 10, 15, 5, 15 ); //sets spacing inside frame
pane.add(row1);
row1.setMaximumSize( new Dimension( 10000, row1.getMinimumSize().height));
row1.setBorder( rowborder);
pane.add(row2);
row2.add(principal_label);
row2.add(principal_txt);
row2.setMaximumSize( new Dimension( 10000, row2.getMinimumSize().height));
row2.setBorder( rowborder);
pane.add(row3);
row3.add(button_label);
row3.setMaximumSize( new Dimension( 10000, row3.getMinimumSize().height));
row3.setBorder( rowborder);
pane.add(row4);
ButtonGroup pickOneGroup = new ButtonGroup(); //creates group for buttons
pickOneGroup.add(oneButton);
pickOneGroup.add(twoButton);
pickOneGroup.add(threeButton);
row4.add(oneButton);
row4.add(twoButton);
row4.add(threeButton);
row4.setMaximumSize( new Dimension( 10000, row4.getMinimumSize().height));
row4.setBorder( rowborder);
pane.add(row5);
row5.add(monthlyPayment_label);
row5.add(monthlyPayment_txt);
monthlyPayment_txt.setEditable(false); //user cannot alter this text
row5.setMaximumSize( new Dimension( 10000, row5.getMinimumSize().height));
row5.setBorder( rowborder);
pane.add(row6);
row6.add(resetButton);
row6.add(exitButton);
row6.add(calculateButton);
row6.add(amortizationButton);
row6.setMaximumSize( new Dimension( 10000, row6.getMinimumSize().height));
row6.setBorder( rowborder);
scroll.setBorder(BorderFactory.createEmptyBorder(10,10,10,10)); //for amortization display
pane.add(scroll);
pane.setLayout(new BoxLayout( pane, BoxLayout.Y_AXIS));
setVisible(true);
setContentPane(pane);
oneButton.addActionListener(this); //button one listener
twoButton.addActionListener(this); //button two listener
threeButton.addActionListener(this); //button three listener
resetButton.addActionListener(this); //reset listener
exitButton.addActionListener(this); //exit listener
calculateButton.addActionListener(this); //calculate listener
amortizationButton.addActionListener(this); //amortization listener
}
public void actionPerformed(ActionEvent event) {
Object command = event.getSource();
//begins error message checking
if(command == calculateButton) {
try {
principal = Double.parseDouble(principal_txt.getText());
}
catch(NumberFormatException e) {
//error message for principal amount
JOptionPane.showMessageDialog(null, "Dollar amounts only please! (ex. 300000)", "ERROR", JOptionPane.ERROR_MESSAGE);
}
}
//resets all amounts to blank
if(command == resetButton) {
principal_txt.setText(null);
monthlyPayment_txt.setText(null);
displayArea.setText(null);
}
//exits the program
if(command == exitButton) {
System.exit(0);
}
if(command == calculateButton) {
double principal=Double.parseDouble(principal_txt.getText()); //retrieving the users input
if (event.getSource() == oneButton) {
length = 7;
interestRate = 5.35;
}
if (event.getSource() == twoButton) {
length = 15;
interestRate = 5.5;
}
if (event.getSource() == threeButton) {
length = 30;
interestRate = 5.75;
}
monthlyInterest = (interestRate/12)/100; //Determines monthly interest rate
months = length * 12; //Changes years to months
monthlyPayment = .005+(principal*monthlyInterest/(1-(Math.pow((1+monthlyInterest),(-months))))); //Determines monthlyPayment
String s = Double.toString(monthlyPayment);
monthlyPayment_txt.setText(s);
}
if(command == amortizationButton) {
double principal=Double.parseDouble(principal_txt.getText()); //retrieving the users input
for(int number = 0; number <= length - 1; number++) {
if (event.getSource() == oneButton) {
length = 7;
interestRate = 5.35;
}
if (event.getSource() == twoButton) {
length = 15;
interestRate = 5.5;
}
if (event.getSource() == threeButton) {
length = 30;
interestRate = 5.75;
}
monthlyInterest = (interestRate/12)/100;
months = length * 12; //Changes years to months
monthlyPayment = .005+(principal*monthlyInterest/(1-(Math.pow((1+monthlyInterest),(-months))))); //Determines monthlyPayment
interestPaid = balance * monthlyInterest + .005; //Determines interest paid amount
premium = monthlyPayment - interestPaid; //Determines premium paid
balance = balance - premium; //Determines loan balance
String titles = "Payment # \t MonthlyPayment \tLoan Balance \t Interest Paid";
displayArea.setText(titles);
displayArea.setText(number+"\t\t"+money.format(balance)+"\t\t"+money.format(interestPaid));
String s = Double.toString(number);
number_txt.setText(s);
balance_txt.setText(s);
interestPaid_txt.setText(s);
}
}
}
public static void main(String[] args) {
Frame f = new Mortgage3();
f.show();
}
}
Re: Looping help needed for math calculation
If you can't troubleshoot and debug a "looping problem" you have no business dabbling in GUIs. May seem harsh to you, but it's true.
Start again from scratch, and create a console app that either prompts for input or uses hard-coded data, which you can edit and change from run to run to make sures the results are consistently correct. When you have that working, go back to your GUI.
And if you can't even get a console app working the way you need it to, you will have a shorter, mor analyzable program to post here and ask for help. I for one have no intention of going through reams of deeply (and poorly) indented GUI code to discover a logic problem. Maybe you'll get lucky and someone else will, but you can greatly improve your chances of getting help by showing the effort to simplify the problem.
db
Re: Looping help needed for math calculation
Also, were you taught to import every Java package you have ever heard of? java.lang.* is imported by default, and I'm sure your code doesn't use half the imports at the top of the code, not to mention the redundant import of individual classes in addition to the star import.
I suspect you copied most of that code from somewhere without understanding any of it. I'll be happy if you prove me wrong.
db
Re: Looping help needed for math calculation
Thank you for your poor response. I thought this was a HELP forum but i guess i was mistaken. I guess this is only a forum for BASHING newbies. Shame on you!
Re: Looping help needed for math calculation
Seeing as how you got told off on forums.devshed.com, you could help yourself to get better help by going through these two links
How To Ask Questions The Smart Way
SSCCE : Java Glossary
db
Re: Looping help needed for math calculation
Quote:
Originally Posted by
pcornacchione
Thank you for your poor response. I thought this was a HELP forum but i guess i was mistaken. I guess this is only a forum for BASHING newbies. Shame on you!
So, you think you have the right to demand help without exerting the effort you could, to make your question more easily answered. Better get a paid tutor, public forums aren't for the likes of you.
Ask yourself why hundreds or even thousands of other members seeking help on various problems do indeed get the help they seek, whereas all you have 'achieved' is being rude to some stranger on the internet at (at least) two forums.
Then decide who should be ashamed.
db
Re: Looping help needed for math calculation
Quote:
Originally Posted by
Darryl.Burke
So, you think you have the right to demand help without exerting the effort you could, to make your question more easily answered. Better get a paid tutor, public forums aren't for the likes of you.
Ask yourself why hundreds or even thousands of other members seeking help on various problems do indeed get the help they seek, whereas all you have 'achieved' is being rude to some stranger on the internet at (at least) two forums.
Then decide who should be ashamed.
db
Owned lmao
Re: Looping help needed for math calculation
Further, on reviewing every word I have posted here, I fail to find any unhelpful post nor any That suggests you are trying to garner sympathy in the hope that some poor sod will hand you the code on a golden platter. I certainly hope that doesn't happen, as it will deny you the opportunity to learn and grow.
db
Re: Looping help needed for math calculation
Re: Looping help needed for math calculation
Too bad, someone just handed him the answer on dream.in.code
Re: Looping help needed for math calculation
Quote:
Originally Posted by
Brt93yoda
Too bad, someone just handed him the answer on dream.in.code
Unfortunately I had some problems logging in there :( And it's her, not him. Use Google ;)
Now she'll never bother to learn. And the questions will get less and less directed till even dream.in.code will give up on her.
db
Re: Looping help needed for math calculation
Come on guys, we are the friendly java community after all!
Yeah the OP may not have not approached this thread in the best possible way but as a new member we should be doing our best to help and hope that they learn from our advice. We don't have to help complete code or do all the work but a gentle nudge in the right direction is all it takes..
Everyone has to start somewhere and everyone has the right to learn from their mistakes.
I appreciate your help guys but found the instant dismissal slightly inappropriate. Please don't take my comments the wrong way.
Re: Looping help needed for math calculation
Quote:
I ... found the instant dismissal slightly inappropriate.
I'd like to know which post you regard as an "instant dismissal"
db
Re: Looping help needed for math calculation
Quote:
Originally Posted by
Darryl.Burke
If you can't troubleshoot and debug a "looping problem" you have no business dabbling in GUIs. May seem harsh to you, but it's true.
Start again from scratch, and create a console app that either prompts for input or uses hard-coded data, which you can edit and change from run to run to make sures the results are consistently correct. When you have that working, go back to your GUI.
And if you can't even get a console app working the way you need it to, you will have a shorter, mor analyzable program to post here and ask for help. I for one have no intention of going through reams of deeply (and poorly) indented GUI code to discover a logic problem. Maybe you'll get lucky and someone else will, but you can greatly improve your chances of getting help by showing the effort to simplify the problem.
db
This first post seemed very dismissive rather than helpful.
But like I say, don't take my comments in the wrong way. People post similar threads to the OP all the time. The only reason I got involved is because it was flagged by a few users.
I appreciate the help you do here on a daily basis.
Re: Looping help needed for math calculation
Quote:
Originally Posted by
JavaPF
This first post seemed very dismissive rather than helpful.
When I wrote it, I thought so too, which is why I added the line
Quote:
May seem harsh, but it's true
before I posted it.
The OP's response was totally uncalled-for
Quote:
Originally Posted by
pcornacchione
Thank you for your poor response. I thought this was a HELP forum but i guess i was mistaken. I guess this is only a forum for BASHING newbies. Shame on you!
I don't believe spoonfeeding helps anyone. Also, I don't believe in encouraging someone new to Java and/or programming to bite off more than they can chew. The question posted here and on at least two other forums is very obviously a homework question; its' also painfully obvious that the student who posted the question has neglected more fundamental aspects of Java that must have been taught along the way and was simply looking for code to submit as her own, aka cheating.
And that's the last I have to say on this topic, regardless of any reactions to what I have already said. No more clarifications, no confrontations. Take it or leave it.
db
