PowerPoint Presentation C3I Systems 2 Lecture 1

1

Program Design II Lecture 4 Supporting
Material Dr Kathryn Merrick Thursday 12th
March, 2009
2
(No Transcript)
3
Overview

• Programming using functions
• Constants and variables
• Operators and built in functions

4
Another Problem
5
Revision From Problem to Program

• Understand the problem in English
• Develop a rough solution on paper
• Implement the solution in MATLAB
• Test your solution

6
Understanding the Meteor Problem
diameter velocity density
7
Physics of a Meteor

• The impact ratio tells us if the meteor will hit
  the earth or break up
• where
• and
• CD is the drag coefficient, assumed to be 2.0
• H is the scale height, assumed to be 8000m for
  Earth
• vi is the velocity
• ?i is the density
• L0 is the diameter
• ? is the angle

8
Example A Meteor Simulator

• The problem in English
• Id like to write a program that can tell me if a
  meteor is going to hit the earth or break up.
• The rough solution
• Im going to write some code that can
  automatically compute the impact ratio, given the
  density, diameter, velocity and angle of the
  meteor.

9
MATLAB Tools Well Need
10
Demo 1 Meteor Simulator in MATLAB
11
Summary

• After todays lecture you should be able to
• Take a problem in English and develop a rough
  solution
• Define simple functions and helper functions as
  reusable solutions to a problem
• Use operators and built in functions as part of
  your solution
• Tell the difference between a variable and a
  constant