= MATLAB

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MATLAB
Mathematics Laboratory


MATLAB
Civil Engineering
Dan Ophir, Ph.D. Cell. 052-551359 e-Mail
comp_ophir_at_yahoo.com
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Requirements

• Tests
• Intermediate,
• Final.

75 Lectures 25 Exercises
Note Tests Exercises
Exercises in diskettes 1. .rtf format
(Office) 2. .m, .mdl, .fig (Matlab)
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Students
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Files
Users

1. .m --- Script
2. .mat --- Workspace
3. .mdl --- Block program Model (Simulink)

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Conventions

1. gt - pressing on a menu, sub-menu, button
2. blue link
3. red a reserved word.

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Mode of Interaction
Interactive Batch Script Program
Interpreter Compiler
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MATLAB - Potential
Type Demo
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Demo
MATLABgtMatricesgtgraphs and matrices MATLABgtNumeric
sgt2D-solutions MATLABgtNumericsgtCommand line
demosgtRun Command line demos gtfunction
plot MATLABgtVisualizationgt3D plots of comples
functionsgtRun 3D plots ofgt Cube root
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Demo (2-cont.)
MATLABgtLanguage/Graphicsgt3d surface plotsgt Run 3D
surface plotsgtcolor map
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Work Environment
Files
Work- Space
Desktop
Windows
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Windows

• Systems
• Commands (history)
• Variables
• Help Window
• Launch Pad
• Workspace (variables)
• Array Editor

• Users
• Script .m
• Module .mdl
• Figure .fig

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Getting Starting
MATLAB Command Window

• First commands
• helpwin list of all .m files (scripts) included
  in the path (described in a help window) gt tips
  (gtSee also, gtBack, gtForward)
• 2. help - a help in the command window.
• 3. help debug a help of special topics or
  command.
• lookfor conversion
• which fprintf

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Interactive Calculation
Command window x5 yx2 disp(y)
files .mat for workspace saving. MATLAB.mat
default file name
use save / load to treat with workspace file
who the local variables values whos the local
variables data structure
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M-File Editor/Debugger window
Input
1. Command window setpath 2. Command window
open fibonaci.m file 3. Command window fibonaci
Output
1. Command window Fibonacci series 2. Figure No.
1
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Fibonnacci
1 1 2 3 5 8 13 21
Converges to the golden ratio.
AB CB CB AC
A
B
C
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Golden Ratio
Parthenon
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Simulink window
Modeling Programming

• First step
• menufilegtnewgtmodel
• or gtopengtbrowsing .mdl
• gives the model specifications.
• 3) model - icon

• Second step
• menu filegtopen
• Browsing for .mdl

• Third step (Integral window)
• menu simulationgtstart
• Input Integration windindows

C\MATLAB_5\my_examples\mdl\MDL\Simple\INTEGRAL.MD
L
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MATLAB as a Language
Language Syntax, Semantics
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Language Components
script function f(a,b) command
xy5 variable myBook_1 operator
constant 3.27 special symbol , ( )
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Operations (operators)
operation symbol example
Addition 32
Subtraction - 54.4 25.3
Multiplication 3.15 6
Division / or \ 23.4/8
Exponentiation 34
helpwingtmatlab\opsgt
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Variables

• Naming rules
• letters, digits, _
• Case sensitive
• Starting with a letter

Reserved World List (17) for end if while
function return elseif case otherwise switch
continue else try catch global persistent break
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MATLAB specialvariables
Special Variables
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Control Flow keywords
if - Conditionally execute
statements. else - IF statement
condition. elseif - IF statement
condition. end - Terminate scope of
FOR, WHILE, SWITCH and IF statements. for
- Repeat statements a specific number of
times. while - Repeat statements an
indefinite number of times. break -
Terminate execution of WHILE or FOR loop.
helpgtmanualgtcontrol flow helpgtelse
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Functions Library
Trigonometric sin, cot Exponential log, exp,
, sqrt Complex conj, real Rounding and
remainder fix, floor, mod Coordinate
Transformation carth2sph,pol2cart Number
Theoretic factor, isprime, gcd Specialized
besselj, legendre
helpwingt matlab\elfun (topics elem. func) gt tan
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Function Syntax
function list of output arguments name
(input-arg.) commands
Example function mean avg(x,n)
mean sum(x)/n
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Command
Command collection of the following
entities variables, constants, calling
functions, keywords (reserved words) and
operators.
Examples x2310sin(0.3)
x
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Program
Program A collection of commands with some
significance.
gtgt fibonnaci - sequence gtgt b(1)1 b(2)1 gtgt
for I35, b(I)b(I-1)b(I-2)
end gtgt b gtgt who
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Example FOR, matrix
Output 2 3 4 5 3 4
5 6 4 5 6 7 5 6
7 8 6 7 8 9
Command gtgt for i15, for j14,
a(i,j)ij end
end gtgt a
basewords loop, matrix, index operators gtgt ,
()
column
row
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Simple for, if
Code
Output
for I15 I end
1 2 3 4 5
I1 J2 X5 X6 if x5 I else J end

1 2
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FAQ
Frequently Asked Questions ????? ??????

gtgt If for
Previous command
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Language Manual
MANUAL.M
MANUAL.M
help manual
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Script, Program, Function
Script, Program, Function A collection of
commands enclosed between two special commands
(module) and having a special task.
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Exercise 1(list)
Choose 8 Reserved words and explain their
function in MATLAB and give examples of their
usage. Use the help features of MATLAB and the
manual.m file.
Choose 5 operators not given in the lecture and
explain their function
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Exercise 2 (Pitagoras)
Input Two perpendicular sides a,b of a
right-angled triangle, Output The length of the
opposite side c. Do To write commands to compute
c.
c2 a2 b2
c
b
a
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Simple Script Sum_Arr
1. a1 2 3 2. n3 3. function fsum(a,n) 4.
Computing the sum of the elements of an
array 5. sum10 6. for i1n, 7.
sum1sum1a(i) 8. end 9. fsum1 10.
ssprintf('sumd',sum1) 11. disp(s)
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Fibonacci Script (recursive)
1. fibonaci.m (recusive algorithm) 2. A script
to calculate Fibonacci numbers 3. first
described by Leonardo of Pisa 4. f1 1 n1 5.
while f(n) f(n1) lt100 6. f(n2)f(n)f(n1)
7. nn1 8. end  
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Exercise 3 (primes)

1. Write a script/function myPrime to print all the
   prime numbers less than n
2. Take n100.
3. Compare the results with those received by using
   the MATLAB original function.

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Line 2D
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Exercise 4 Triangle
Draw (in the .m file) a triangle ,whose vertices
are at the points (5,5), (0,10), (10,10)
???? (???? .m) ????? ????????? ??????? ?????
(5,5),(0,10),(10,10)