Java Newbie Needs Help

[lonlonmalon]

Hi there, I am fairly new to Java and am doing my best to work with it, but I am having a major problem with one of my programs.

What the program does is, the user will enter an initial balance and a rate of interest to be compounded annually. The program then returns the balance the user will have at the end of each year until it reaches ten years.

However, according to my adventures in grade 12 math, the results are seriously wrong. Here is my code:

import java.io.*;

public class CompoundInt {
    
    public static void main(String[] args) throws IOException 
    	{
		
			BufferedReader myInput = new BufferedReader (new InputStreamReader (System.in));    	
		
			System.out.print("What is the initial balance?" + '\t');
			String initialBalance = myInput.readLine();
			double inBalance = Double.parseDouble(initialBalance);
			
			System.out.print("What is the rate of interest(annually compounded)?" + '\t');
			String stringRateOfInterest = myInput.readLine();
			double rateOfInterest = Double.parseDouble(initialBalance);	
    	
    		System.out.println(" ");
    		
    		compound(inBalance, rateOfInterest);
    	}
    static public void compound (double deposit, double rate) 
    {
    		double endDeposit;
    		int loopNumber = 0;
    		System.out.println("Year" + '\t' + '\t' + "Final Balance");
    		rate = 1 + (rate / 100);
    		
    		while (loopNumber < 10)
    		{
    			loopNumber++;
    			endDeposit = (deposit * (Math.pow(rate, loopNumber)));
    			System.out.println("Year " + loopNumber + ":" + '\t' + endDeposit);		
    		}
    }    
}

EDIT: I don't know how clear it may be in the code, but the output is totally wrong. For example, say that the initial balance is 100 and the rate of interest is 5%. According to my EXTENSIVE calculations, at the end of year 1, the user should have $105. The next year they should have $110, etc. However, according to this program, the user will have 200 the first year, 400 the next, 800 the third year, etc.

[CornedBee]

Your extensive calculations are wrong. (That doesn't make your program right - just saying.) After one year, the deposit is 105. But the next year, the 5% are calculated from that, so the third year should show 110.25.

I don't see an obvious error in the program, though. Perhaps store the result of Math.pow() in a temporary and write it out, so you can check what your program does.

[lonlonmalon]

I admit I was a little lazy after doing the first year's calculation. Thanks for the correction. :P

But I will try out your idea ASAP.

[TBeck]

I was checking the math and it seems to be alright, then I noticed this part:

double rateOfInterest = Double.parseDouble(initialBalance);

the bold should be replaced with stringRateOfInterest

[CornedBee]

Whoa, good catch! The dreaded copy&paste.

That's why I always use one variable for all temporary strings. I call it "t" or "temp" or something like that.

[lonlonmalon]

Ahhh, I see. Thanks a lot!

That's what I get for programming late at night :P