1. Engineering 1020 Introduction to Programming Peter King peter.king@mun.ca www.engr.mun.ca/~peter Winter 2010

2. ENGI 1020: Examples • Lecture example from last class *

3. ENGI 1020: Examples • IDE • Integrated Development Environment • Eclipse • Teaching Machine • Editing, compiling and debugging all under one roof • Multiple source files open at once

4. ENGI 1020: Examples • Debugging • After you hit 'build', the real fun starts • Start at the top • 1 error tends to lead to another • Think logically • What's missing? • Typing error? • Wrong type? • Fresh eyes

5. ENGI 1020: Examples • Ex #1 • In pre-calculus physics the distance an object travels is given by the formula: • s = ut + 1/2at2 • where u is the initial speed, a is a constant acceleration and t is the time. • Create a function to compute s plus a main function to that tests it by calling it with some values.

6. ENGI 1020: Examples • #1 • What's the contract? • What data are we agreeing to return? • #returns • What data do we require? • #params • @pre • What should we call the function?

7. ENGI 1020: Examples • #2 • Create a function to compute the area of a circle given its radius (note that a value for PI is not built in to C++ so use 3.14159) plus a main function to that tests it by calling it with some values.

8. ENGI 1020: Examples • #2 • What's the contract? • What data are we agreeing to return? • #returns • What data do we require? • #param • @pre • What should we call the function?

9. ENGI 1020: Examples • #3 • Lets do a simple example, but with more utilization of variables. • Write a function that returns the square of a number. • Write a main function that calls our function once, and then again with the result of the first call • The output would look like: • The square of 2 is 4 • The square of the square of 2 is 16