CS173: Intro to Computer Science - Introduction to Iteration (3 Points)

Developed by Professor Tralie and Professor Mongan.

Exercise Goals

The goals of this exercise are:
  1. To use iteration to compute a discrete value
Modify the Driver.java file to compute compound interest using a loop to compute the overall interest rate.

Enter your Ursinus netid before clicking run. This is not your ID number or your email. For example, my netid is wmongan (non Ursinus students can simply enter their name to get this to run, but they won't get an e-mail record or any form of credit).

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public class Driver { public static void main(String[] args) { // balance = principal * totalInterestRate // totalInterestRate = totalInterestRate * compoundFactor, computed n*t times // ... where compoundFactor = (1 + (rate / n)) // ... where t = periods (years), n = compoundTimesPerPeriod (times per year), // ... and rate = annual interest rate (2% == 0.02) int principal = 1; // 1 dollar invested double interest = 1; // at 100% interest int years = 1; // for 1 year /* TODO: Change this to compound daily */ int compoundTimesPerYear = 12; // compounded monthly double compoundFactor = 1 + (interest / compoundTimesPerYear); double totalInterestRate = compoundFactor; // iterate one fewer time because we initialized the variable above, which counts as one multiplication for(/* TODO: Fill this in */) { totalInterestRate = totalInterestRate * compoundFactor; } double finalBalance = principal * totalInterestRate; System.out.println(finalBalance); System.out.println(totalInterestRate); } }


Fun With Limits

As your compoundTimesPerYear variable increases, your total balance approaches a certain famous constant: what is it?