Engineering computation with MATLAB 3^rd Edition Chapter 6 Problem 4

The function rot(s, n) is a simple Caesar cipher encryption algorithm that replaces each English letter in places forward or backward along the alphabet in the strings. For example, the result of rot(Baz!,3) is Edc!. An encrypted string can be deciphered by simply performing the inverse rotation on it, i.e., rot(Edc!,3), which rotates each English letter in the strings three places to the left. Numbers, symbols, and non-letters are not transformed. Implement the following function:

function rotatedText=rot(text,n)

To assist you as you solve this problem, you could write several functions as local functions in the rot.m isUppercaseLetter(letter), getUppercaseLetter(n), getLowercaseLetter(n), and getPosition(letter). You may also wish to use the built-in MATLAB functions isletter(), find(), and mod().