300027

Engineering Computing
 Engineering Computing 300027
• Unit Coordinators
– Dr. Upul Gunawardana, PS-ED.G.122, Tue 11-12
Email: u.gunawardana@westernsydney.edu.au
– Dr Mark Wang, KWD-XB.2.43, Wed 11-1
Email: m.wang@westernsydney.edu.au

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 Lecture
• Parramatta & Kingswood Campuses
Mazin Aouf, Email: m.aouf@westernsydney.edu.au

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 What is Engineering?
• To ‘engineer’ means to make things happen
• Engineering involves application of scientific knowledge to the
design, build and control of machines, buildings, roads, bridges,
electrical equipment, etc.
• Analyse, model and solve complex technical problems that require
integrated, interdisciplinary view of problem solving
• Conceptualize complex systems as a collection of smaller, simpler
components
• Development and use of mathematical simulation models.
• Synthesis and design by taking into account factors such as
reliability, safety, flexibility, economy and sustainability

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 Why Engineering Computing?
• Engineers use all forms of mathematical simulation models
and tools
• During the B Eng degree (vary from key area to key area)
– MATLAB, Simulink
– SolidWorks, Autocad
– NI LabView, Multisim, Ultiboard, Altium Designer
– Ansys models
– Abaqus, Microstrain
– Programming Languages such as C++, C#, C, Visual Basic, Python
– Spreadsheet applications such as Excel

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 WHS & SCEM
• Work Health and Safety (WHS) Induction
– Login to vUWS and select 2019 Work Health and Safety
vUWS site
– Go through learning material
– Take the test – you need to get at least 23 of 25 correct
– Need to complete WHS induction before attending lab
classes
• SCEM Accounts
– Need SCEM account to access Engineering computer labs
– Different to Western Sydney account (which is all numbers)
– Login to a SCEM computer using username as ‘register’ and
password as ‘register’ and follow the process
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 Engineering Computing: Learning
Outcomes
At the conclusion of this unit, students will be able to:

1. Utilise a typical software development environment.

2. Develop solutions to problems using an algorithmic approach.
3. Apply data structures of a common programming language, such as C++,
to translate an algorithm into a coded program. These programming
structures should include the following as a minimum:
• Selection and Repetition statements
• Functions
• 1 & 2 dimensional Arrays
• File processing
4. Implement basic features of data manipulation and graphing using a
spread sheet program, such as EXCEL.

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 Textbook and Software
• MATLAB
• Textbook: Essential MATLAB (6th edition) by Hahn and
Valentine, Elsevier
• Software: MATLAB (information for downloading
MATLAB available on vUWS)
• C++
• Software: Microsoft Visual Studio (or access to a similar
C++ development environment) / Xcode / Dev C++
• Excel
• Software: Microsoft Office

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 Additional Resources
• MATLAB
– Textbook: Gilate, A, (2014), “MATLAB: An Introduction
with Applications”, 5th Ed., Wiley
• C++
– Textbook: Gaddis, T, (2012), "Starting Out with C++ from
control structures through objects," 7th Ed., Addison-
Wesley
– Website: C++ Tutorial & Forum
http://www.cplusplus.com/doc/tutorial/
• Excel
– Textbook: Larsen, Ronald W., (2013) "Engineering with
Excel", 4rd Ed., Pearson
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 What is useful?
• Lectures
– Lecture notes
– Textbook (hardcopy or softcopy)
– If you have a laptop with MATLAB installed you may
bring that to lecture and lab classes
• Lab Classes
– WHS Induction must be completed with a Pass Grade
– Must be wearing covered shoes
– A USB drive to save your work
– Complete previous lab questions
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Teaching and Learning Activities

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 Academic Misconduct
• Read definitions of collusion and plagiarism as
explained in Western Sydney University Academic
Misconduct Policy
• All quizzes and exams will be individual work

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 Assessment Details
MATLAB MATLAB program to be submitted in
Programming 20% the practical session, open book, 4
Quiz 1 questions (Week 5)

MATLAB MATLAB program to be submitted in

Programming 30% the practical session, open book, 4
Quiz 2 questions (Week 10)

C++ C++ program to be submitted in the

Programming 10% practical session, open book, 2
Quiz 3 questions (Week 14)

Multiple choice, closed book, 50

Final Exam 40% questions: 35 MATLAB, 13 C++, 2
Excel (TBA)
Introduction to MATLAB

Content based on the text:

Essential MATLAB
for Engineers and Scientists, 6th Edition
By
Brian H. Hahn & Daniel T. Valentine
 Outline
• What is MATLAB?
• How is MATLAB used in industry?
• Problem Solving in Engineering and Science
• Introduction to MATLAB
– How to get started with MATLAB
– Learn how to do technical computing with
MATLAB

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 What is MATLAB?
• MATLAB is one of a number of commercially
available, sophisticated mathematical
computation tools
• Others include
– Maple
– Mathematica
– MathCad
– Octave

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 MATLAB excels at:
• Numerical calculations
– Especially involving matrices
• Graphics
• MATLAB stands for
Matrix Laboratory

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 Why MATLAB

• Easy to use
• Versatile
• Built in programming language
• Not a general purpose language like C++ or Java
MATLAB was originally written in Fortran,
then later rewritten in C

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 MATLAB
• The Mathworks packages their software in groups,
called releases
• New releases are issued twice a year in the spring
and in the fall (2016a, 2016b, etc.)
• MATLAB Releases include the base MATLAB,
Simulink and a set of specialized “toolboxes”
• MATLAB is updated regularly

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 How is MATLAB used in Industry?
• Widespread, especially in the signal processing field
• Tool of choice in Academia for most engineering fields
• MATLAB is used in Industry in a number of fields such
as Biomedical Engineering, Electrical Engineering, Fluid
Dynamics, Financial industry, Biological Sciences, etc.

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 Problem Solving in Engineering and Science
1. State the Problem
– If you don’t have a clear understanding of the problem, it’s
unlikely that you’ll be able to solve it
– Drawing a picture often helps you understand the system better
2. Describe the input and output
– Be careful to include units and identify constants
3. Develop an algorithm
– Identify any equations relating the knowns and unknowns
– Work through a simplified version of the problem by hand or with
a calculator
4. Solve the problem
– Create a MATLAB solution
– Be generous with comments, so that others can follow your work
5. Test the solution
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 Test the Solution
• Compare to the hand solution
• Do your answers make sense physically?
• Is your answer really what was asked for?
• Graphs are often useful ways to check your
calculations for reasonableness

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MATLAB desktop

Command Window
Workspace Window
Command History
Window

Current Directory
Window

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 Command Window
• The Command Window in the center is the main
panel where you interact with MATLAB.
• You key (or type) and <Enter> commands after the
prompt >>; MATLAB executes the commands and
displays results (if requested).
• Some commonly used tools and commands:
–  (up arrow) returns last command input, can be repeated
– clc – clears the screen
– whos – shows list of variables
– clear – clears variables

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 Evaluation of MATLAB
• HANDS-ON with MATLAB
– Type
>> 2+3 <Enter>
into the Command Window
>> clc <Enter>
>> whos <Enter>
Throughout the lecture, yellow text indicates what you
should type into MATLAB.

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 Command History Window
• The Command History Window logs all of the
commands you enter in MATLAB.
• It should have logged 2+3.
Use the Command History Window to reenter 2+3 in
the command window (use copy-and- paste or
double click on 2+3).
• This is useful to retrieve past commands.
• Use “Shift” key to select multiple lines.

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 Arithmetic with MATLAB
• Let us explore by doing exercises:

>> 3–2 <Enter>

>> 3*2 <Enter>
>> 3/2 <Enter>
>> 3\2 <Enter>
>> 3^2 <Enter>
>> 2/0 <Enter>
>> 0/2 <Enter>
>> 3*Inf <Enter>
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 Algebraic-numeric computations
• Let us explore by doing exercises:
>> a = 3 <Enter>
>> b = 2 <Enter>
>> a – b <Enter>
>> a / b <Enter>
>> a^2 <Enter>
>> c = a * b <Enter>
>> d = c^(b+1) <Enter>
>> who

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 Hiding Output with ;
• Let us explore by doing exercises:
>> clear; clc <Enter>
>> whos <Enter>
>> a = 3; <Enter>
>> b = 2; <Enter>
>> c = a * b; <Enter>
>> d = c^(b+1); <Enter>
>> who <Enter>
>> % a, b, c, d are in workspace<Enter>
>> a, b, c, d <Enter>

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 Plot y versus x
• Introduction to plotting & displaying data:
>> clear; clc <Enter>
>> x = 0:0.1:1; <Enter>
>> y = x.^2; <Enter>
>> whos <Enter>
>> plot(x,y,’-o’) <Enter>
>> disp(' '),disp('...... x ........ y .....'),disp([x‘ y']) <Enter>
>> x <Enter>
>> y <Enter>
>> % x and y are 1-by-11 arrays of numbers!

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 Write a Simple Program
• Consider computing the volume of a cone:
Volume = (pi.*r.^2.*h)./3
radius = 6 cm
height = 12 cm

• In the command window key in:

>> clear; clc <Enter>
>> r = 6 <Enter>
>> h = 12 <Enter>
>> v = (pi.*r.^2.*h)./3 <Enter>
>> whos <Enter>

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 Editor & M-Files
• An M-file in MATLAB is analogous to a txt-file
in Microsoft Notepad.
• An M-file is created in MATLAB text editor.
• M-files:
– You can save your programs (i.e., list of
executable commands) as M-files.
– You can reopen and modify your program.
– They are useful for “debugging” (correcting errors)
as you develop your programs (your technical
computing tools).
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 Comments in programs
• Every time you write a program to be saved, it is
helpful for you to comment (i.e., describe) it well.
• To insert a comment on a line in the editor or in the
Command Window, use the comment operator %,
then type your comment.
• MATLAB:
– will not run lines that begin with the comment operator (in
the editor comments appear in green).
• Comments
– Comments allow you (and others) to more easily read and
understand your program.
– When your lines of code are easy to understand, your code
will be easier to use later.
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 Art of well-written code
• A well-written program contains comments
explaining:
– what your program requires as input.
– what the variables in the program represent.
– what your program computes and displays.
• It is useful for you to add a set of header
comments that include the name of the
program, your name (as the programmer), and
the date the program was created or modified.

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 Saving code in an M-File
• Open the editor by:
– Entering the command edit in the command window.
– Or click the New Script icon located at the left most side of
the toolbar.
• Now enter the lines of code to find the volume of a cone:
rr = 4
h = 12
v = (pi.*r.^2.*h)./3
REMARK: If you save it, add header comments and comments
explaining what the program does.
• After you have typed in the code, save it as cone.m.

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This is cone.m in the editor

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 Execute an M-file as a Command
• Now execute (or run) the program by pushing F5, or
by typing on the command line
>> cone <Enter>
– or by clicking the run button. (Note that the run button looks like a
green arrowhead pointing to the right in the Editor toolbar.)
• If you entered the code as written on the previous
slide you will get an error!
• What went wrong?
• Repair your program (Change rr = 4 to r = 4.), save it, and
run it again.
• Now change the height to 24, save and run your
program again (clicking the run button saves and
executes your code).
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 Summary
• MATLAB can be used like a hand calculator to do
arithmetic.
• You can define (or assign) variables with numbers
and expressions to do calculations as illustrated by
the volume-of-cone example.
• The advantage of saving programs as M-files is that
you open it, make changes and/or execute it again
without having to type it all over again.
• This concludes our overview of MATLAB and a taste
of things to come!

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