Other variations

Other variations

The interest example showed us incrementing on each loop, but we didn't start at 0 or 1.

Other variations are possible. We could count down instead of up:

    for (int countdown = 10; countdown >= 1; countdown--) {
        System.out.println(countdown);
    }
    System.out.println ("Blast off!");

We could increment by a value other than 1. For example, we could have kept our interest rate as a double and then incremented by .01.

    private double amount = startInvestment;  // value of investment

    private static final double START_RATE = .02;   // interest rates
    private static final double END_RATE = .12;
    private static final double RATE_INCREMENT = .01;

    private static final int YEARS = 10;      // number of years for investment

    for (double rate = START_RATE; rate <= END_RATE; 
                       rate = rate + RATE_INCREMENT) {
        amount = startInvestment;
        for (int yearNum = 1; yearNum <= YEARS; yearNum++)
        {
            amount = amount + amount * rate;
        }
        System.out.println("At "+ (rate * 100) +"%, the amount is: "+amount);
    }

Warning: Note that you need to be very careful when testing for equality of floating point numbers. Due to roundoff errors, your numbers might not be what you expect.

Other variations