introduction to the p5 computing lab - university of dwm/courses/1p5_2011/1p5lec...intro to p5 mt...
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Intro to P5 MT 2011
Introduction to the P5 Computing Lab
Lab OrganizerProf David Murray
[email protected]/∼dwm/Courses/1P5
Michaelmas 2011
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Intro to P5 MT 2011
Lecture 1
The aim of the laboratory
Practical stuff about the labs
The Linux OS: your filestore
A quick word about Matlab
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I: Aims of the laboratory
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Intro to P5 MT 2011
Aims ...
To begin to equip you with computing competencies ...
that will be used throughout your four years at Oxford forproject work, and so on
that will be useful as an aide to learning when bashing outwork for tutorials
that are central to the professional engineer’s working life— nomatter which speciality you eventually pursue.
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Importance of computing in modern engineeringcannot be over-stated
Pervasive in every aspect
synthesis of complex systems (modelling)
analysis of data from experiments
product design and development
real time control of equipment from washing machines tothe space shuttle
communications, web, video, audio
Some examples ...
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Complex mechanical design: Millau viaduct
Cable-stayed, masted structureSection span 350 mOverall span 2.5 km
Tallest column 245 mMast height 90 m
Let’s build a set of Eiffel towers ...
perch a road deck across the topof each
stick 90 m masts on the top
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CFD: Weather forecasting/F1 Development
Navier-Stokes equations — no analytical solution
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Medical Imaging
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Intro to P5 MT 2011
Robotics
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Intro to P5 MT 2011
Comms, Electronic Design: Smartphones
600 MHz ARM processor1GB RAM32GB storageOpenGL graphicsLinux OSUSB, BluetoothGPS, Camera, etc≡ PC circa 2000
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Maths + Physics + Software
Being able to use a computer to solve engineering problems isa core skill
It requires mathematical analysis and physicalunderstanding of the problem at hand
but also software skills to write a program to satisfy somea-priori purpose ...
... compute heat transfer in a turbine blade ...... model blood flow in the heart ...
Both are a bit ambitious for your first day so you will start withsomething simpler
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Simulate flight of a Saturn V Rocket
Vital StatisticsHeight 110mMax Diameter 10 mInitial Mass 2900 tonnesTotal Launch Thrust 34000 kNStage 1 Burn Time 150 sStage 1 Fuel Mass 2150 tonnes
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II: About the labs
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Five × 5-hour sessions
Using the machines on Level 6
The first two lab sessions will introduce you to
the Linux operating system
Matlab — a powerful programming language andenvironment
In the later three lab sessions you
make your own design decisions
write Matlab to simulate rocket flight and controlled landing
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What is required from an academic perspective?
Read through notes the night before
Turn up with lab notes, logbook, cover sheet
Engage brain. Work steadily through the notes, try out thevarious examples AND explore for yourself
Do not worry about getting stuck. There is time to thinkhow to get unstuck, and demonstrators on hand to helpyou (but not to tell you the answer).
Complete the exercises in a timely fashion; make briefnotes in your logbook as you go.
Get assessed — present your results and code to ademonstrator
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The demonstrators’ favourite student
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What is required from a practical perspective?
Turn up on time (no later than 11.05 and 14.05).
Contact the lab organizer by email if you are unable tomake a session through some serious unavoidablecommitment.
Have fun. The labs are meant to be enjoyable ...
... for the demonstrators at least.
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What when? The 8 sets of exercises
Set Purpose Complete by end0 Basic Unix skills EOF Session 1I Basic Matlab Skills EOF Session 1II Extended Matlab Skills EOF Session 2III Simple Dynamics Simulation EOF Session 3IV Simulate Time Varying Dynamics EOF Session 3V Use of structures. Code design and form EOF Session 4VI Thinking in modules EOF Session 5VII Using simulator as a design tool EOF Session 5
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Formal assessmentsThere are three assessments
1 At the end of Exercise Set I(and no later than 11.30am of your 2nd session)
2 At the end of Exercise Set II(and no later than 4.30pm of your 2nd session)
3 At the end of Exercise Set VII(and not later than 3.00pm of your 5th session)
These are not terrifying!
The demonstrators will wish to seeyour logbook, your code (commented and working),and may ask you a few on-the-spot questions.
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III: Unix and your filestore
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The only way to learn computing is to do computing
True, but this heads-up on using Unix commands to organiseyour filestore is needed because most of you are familiar withthe Windows style of iconic file manager
Instead you areurged to talk to the operating system by typing commandsinto a terminal windowdiscouraged from drag and drop
Why? Allows much more subtle control, is much faster, and willamaze your friends.
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The terminal window
After logging in, opening a“terminal window” allows you totalk directly to the operatingsystem using Unix commands.
We will worry here about Unixcommands for organizing yourfilestore
And for this you need to picturefile structures as trees(er, upside down trees)
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Current working directory: pwdThe root directory is at the topof the diagram
Opening a terminal windowsets you “working” in yourhome directory
Find where you are workingusing%pwd ←↩/u11/abc
Actually probably says%pwd ←↩/home/ENG/u11/abc
At the moment, there are noother files or directories in it
u11
abc
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Edit and save a file using gedit
Imagine using a text editor tocreate a file called list.txt%gedit list.txt ←↩
Type anything, then save.
Your filestore now changes ...
List your files using%ls ←↩list.txt
u11
abc
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Edit and save a file using gedit
Imagine using a text editor tocreate a file called list.txt%gedit list.txt ←↩
Type anything, then save.
Your filestore now changes ...
List your files using%ls ←↩list.txt
list.txt
u11
abc
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Intro to P5 MT 2011
Edit and save a file using gedit
Imagine using a text editor tocreate a file called list.txt%gedit list.txt ←↩
Type anything, then save.
Your filestore now changes ...
List your files using%ls ←↩list.txt
list.txt
u11
abc
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Intro to P5 MT 2011
Make directories: mkdir
Make two new directoriesunder your current directory%mkdir P5lab docs ←↩
Again list using%ls ←↩docs list.txt P5lab
list.txt
u11
abc
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Make directories: mkdir
Make two new directoriesunder your current directory%mkdir P5lab docs ←↩
Again list using%ls ←↩docs list.txt P5lab
list.txtdocsP5lab
u11
abc
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Make directories: mkdir
Make two new directoriesunder your current directory%mkdir P5lab docs ←↩
Again list using%ls ←↩docs list.txt P5lab
list.txtdocsP5lab
u11
abc
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Change directory: cd
Change your working directorywith%cd P5lab ←↩
Check where you are “working”%pwd ←↩/u11/abc/P5lab
and what files are there%ls ←↩
You see nothing because thereare no files or directories underP5lab
list.txtdocsP5lab
u11
abc
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Intro to P5 MT 2011
Change directory: cd
Change your working directorywith%cd P5lab ←↩
Check where you are “working”%pwd ←↩/u11/abc/P5lab
and what files are there%ls ←↩
You see nothing because thereare no files or directories underP5lab
list.txtdocsP5lab
u11
abc
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Intro to P5 MT 2011
Change directory: cd
Change your working directorywith%cd P5lab ←↩
Check where you are “working”%pwd ←↩/u11/abc/P5lab
and what files are there%ls ←↩
You see nothing because thereare no files or directories underP5lab
list.txtdocsP5lab
u11
abc
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Intro to P5 MT 2011
Change directory: cd
Change your working directorywith%cd P5lab ←↩
Check where you are “working”%pwd ←↩/u11/abc/P5lab
and what files are there%ls ←↩
You see nothing because thereare no files or directories underP5lab
list.txtdocsP5lab
u11
abc
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Intro to P5 MT 2011
Change directory: cd
Change your working directorywith%cd P5lab ←↩
Check where you are “working”%pwd ←↩/u11/abc/P5lab
and what files are there%ls ←↩
You see nothing because thereare no files or directories underP5lab
list.txtdocsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txtdocsP5lab
u11
abc
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Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
docsP5lab
u11
abc
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Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mprog.m
docsdocsP5lab
u11
abcabc
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Intro to P5 MT 2011
Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mprog.m
docsdocsP5lab
u11
abcabc
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Intro to P5 MT 2011
Make more directories%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mprog.m
docsdocsP5lab
u11
abcabc
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Intro to P5 MT 2011
Make more directories
%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories
%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories
%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories
%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Make more directories
%mkdir sess1 sess2 ←↩
%cd sess1 ←↩
%gedit prog.m func.m ←↩
How to cd into sess2?Go up then down%cd ../sess2 ←↩
How would we copy func.m intothis directory?%cp ../sess1/func.m .←↩
How to cd to “docs” from“sess2”?
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Moving up and copying%cd ../../docs ←↩OR%cd ∼/docs ←↩
∼ is short for the path to yourhome directory∼ ≡ /u11/abc
Then edit another file%gedit a.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
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Moving up and copying
%cd ../../docs ←↩OR%cd ∼/docs ←↩
∼ is short for the path to yourhome directory∼ ≡ /u11/abc
Then edit another file%gedit a.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Moving up and copying
%cd ../../docs ←↩OR%cd ∼/docs ←↩
∼ is short for the path to yourhome directory∼ ≡ /u11/abc
Then edit another file%gedit a.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Moving up and copying
%cd ../../docs ←↩OR%cd ∼/docs ←↩
∼ is short for the path to yourhome directory∼ ≡ /u11/abc
Then edit another file%gedit a.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
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Intro to P5 MT 2011
Moving up and copying
%cd ../../docs ←↩OR%cd ∼/docs ←↩
∼ is short for the path to yourhome directory∼ ≡ /u11/abc
Then edit another file%gedit a.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
a.txt
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Typing files at the console: more
Change to your home directory%cd ∼ ←↩
Page by page listing%more list.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
a.txt
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Typing files at the console: more
Change to your home directory%cd ∼ ←↩
Page by page listing%more list.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
a.txt
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Typing files at the console: more
Change to your home directory%cd ∼ ←↩
Page by page listing%more list.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
ugrads
u10abc
a.txt
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Intro to P5 MT 2011
Typing files at the console: more
Change to your home directory%cd ∼ ←↩
Page by page listing%more list.txt ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
ugrads
u10abc
a.txt
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Intro to P5 MT 2011
DeletingDelete a file once in the homedirectory%cd ∼ ←↩%rm list.txt ←↩
Delete a directory recursively%rm -r docs ←↩Watch out!There is no waste bin
What files would this list?%ls ←↩
list.txt
sess1 sess2
func.mfunc.mprog.m
docsP5lab
ugrads
u10abc
a.txt
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Deleting
Delete a file once in the homedirectory%cd ∼ ←↩%rm list.txt ←↩
Delete a directory recursively%rm -r docs ←↩Watch out!There is no waste bin
What files would this list?%ls ←↩
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
a.txt
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Intro to P5 MT 2011
Deleting
Delete a file once in the homedirectory%cd ∼ ←↩%rm list.txt ←↩
Delete a directory recursively%rm -r docs ←↩Watch out!There is no waste bin
What files would this list?%ls ←↩
sess1 sess2
func.mfunc.mprog.m
docsP5lab
u11
abc
a.txt
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Intro to P5 MT 2011
Deleting
Delete a file once in the homedirectory%cd ∼ ←↩%rm list.txt ←↩
Delete a directory recursively%rm -r docs ←↩Watch out!There is no waste bin
What files would this list?%ls ←↩
sess1 sess2
func.mfunc.mprog.m
P5lab
u11
abc
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Intro to P5 MT 2011
Deleting
Delete a file once in the homedirectory%cd ∼ ←↩%rm list.txt ←↩
Delete a directory recursively%rm -r docs ←↩Watch out!There is no waste bin
What files would this list?%ls ←↩
sess1 sess2
func.mfunc.mprog.m
P5lab
u11
abc
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Intro to P5 MT 2011
Deleting
Delete a file once in the homedirectory%cd ∼ ←↩%rm list.txt ←↩
Delete a directory recursively%rm -r docs ←↩Watch out!There is no waste bin
What files would this list?%ls ←↩
sess1 sess2
func.mfunc.mprog.m
P5lab
u11
abc
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Intro to P5 MT 2011
IV: Some quick remarks about Matlab
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Why Matlab? I always use Java/C/C++/C#/Lisp/Z
Matlab is ideally suited for engineers for the following reasons.
It is very strong for numerical computing.Gives access to gold-standard numerical methods
It is a compact and powerful programming language withmany of the constructs of modern languages.
It provides fantastic ways to visualise data (2D/3D graphs,animation, surface meshing etc).
It allows interactive code development.
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Why Matlab? Even more reasons ...
It is very widely used in industry and universitiesinternationally. It is not a toy language.
It runs on all major operating systems —your code is always operating system neutral.
It provides a conservative programming environment.Code written today is likely still to work in 10 years time.In other environments, code can “rot” in a remarkably shorttime.
It is a very intuitive language, with almost no overheadinvolved in getting going.
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Matlab is built on vector and matrix operations
While Matlab handle scalars and strings as any language
Week = 1;Term = ’Michaelmas’;Temp = 21.5;
A key aspect is that it makes vectors and matrices easy torepresent
a = [ 3 -2 1];b = [ 2 -4 -3];c = [-1 2 2];
v = a + b + c;mag2 = sqrt( dot(v,v) );
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Another example ...
To solve an example of Mx = b, 3 2 11 2 3−1 0 2
x1x2x3
=
1014
5
code in
M = [ 3 2 1; 1 2 3; -1 0 2] % 3 by 3 matrixb = [10; 14; 5] % 3 by 1 column vector
then
x = inv(M) * b;
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Element operations are possible to
If you have a vector v and want a new vector w whoseelements are wi = v2
i , you can write for example
v = [ 1 2 3 4 5 6 7 8 ];w = v .* v; % dot times
This idea works on matrices too!
A = [1, 2; 3, 4]B = [5, 6; 7, 8]C = A * B % Mathematical multiplicationD = A .* B % Element by element!
A =
[1 23 4
]B =
[5 67 8
]A∗B =
[19 2243 50
]A.∗B =
[5 12
21 32
]
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Intro to P5 MT 2011
And finally ..
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What to do at Session I
0 Bring notes, cover sheet, logbook, & yellow form1 Find a computer (not too hard ...)
2A If you’ve never logged in via the drawing officeLog in using your single-sign-on usernamebut with password ugrad2011Change password to your single-sign-on password%passwd ←↩and follow the instructions.
2B But if you haveLog in using your s-s-o usernameand s-s-o password.
3 Carry on
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Learning outcomes ....
You willlearn key aspects of proceedural programming: variables,flow control, functions and abstraction.
acquire Matlab as a tool for engineering computation (andthe rest of this course)
be exposed to software design
have to use you code to analyse a complex system that isotherwise beyond your reach
be enthused (we hope!) about the possibilities moderncomputing offers the engineer.
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