Introduction to MATLAB - Cairo Universityscholar.cu.edu.eg/?q=mostafa_elshahed/files/lec_1_0.pdf · Introduction to MATLAB (MATrixLABoratory) ... Final Exam 30 Grades----- Total Grade

1

Introduction to MATLAB

(MATrix LABoratory)

Presented By:

Dr Mostafa ElshahedAsst. Prof.

1Faculty of Engineering, Cairo University

Upon completing this course, the student should be able to:

Learn a brief introduction to programming in MATLAB. Create the MATLAB Scripts (m file) and use its help. Define the different Variables and Operations. Formulate the User-Defined Function. Discriminate between different basic flow-control. Construct the line plots, surface plots, and animations. Solve equations and curve fitting using MATLAB. Use MATLAB debugger to fix the errors. Explore Probability and Statistics commands. Utilize some MATLAB toolboxes: Simulink and

SimPowerSystems.

2Faculty of Engineering, Cairo UniversityDr. Mostafa Elshahed

2

Textbooks

• A. Gilat , MATLAB: An Introduction with Applications, 4th Ed., John Wiley & Sons, Inc.,2011.

• Getting Started with MATLAB, Mathworks Inc., 2011.

• http://www.cyclismo.org/tutorial/matlab/


Assessment

• Lab Attendance: Two Labs (Two Sheets)

• Grades Policy: (For Part 4 only)

Quiz 05 Grades

Project 05 Grades

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Final Exam 30 Grades

-----------------------------------------------

Total Grade 40 Grades

Dr. Mostafa Elshahed Faculty of Engineering, Cairo University 4

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MathWorks®

MATLAB®

R2012a (7.14)

MATLAB

Is an integrated technical computingenvironment that combines numeric computation,advanced graphics and visualization, and a high-levelprogramming language.

The MathWorks, Inc.

High-level language of technical computing

Development environment for engineers, scientists

Interactive tools for design, problem solving

Mathematical function libraries

Graphics and data visualization tools

Custom GUIs

External Interfaces: C, C++, Fortran, Java, COM, Excel, .NET6Faculty of Engineering, Cairo UniversityDr. Mostafa Elshahed

4

MATLAB product family

Toolboxes: Collections of specialized Functions

Graphics

2D Graphics3D GraphicsColor & LightingAnimationImage, Audio & Video

Computations

Linear AlgebraData AnalysisPolynomialsInterpolationsSolutions of ODE

External Interfaces

CC++JAVA.netMicorosoft Excel

Parallel ComputingMath, Statistics, and OptimizationControl System Design and AnalysisSignal Processing and CommunicationsImage Processing and Computer VisionTest and Measurement

Built-in Functions

User-written Functions

MATLAB

Computational FinanceComputational Biology

Code Generation and VerificationApplication Deployment

Database Connectivity and Reporting

MATLAB Programming Language

Parallel Computing ToolboxMATLAB Distributed Computing Server

Parallel Computing Symbolic Math ToolboxPartial Differential Equation ToolboxStatistics ToolboxCurve Fitting Toolbox

Optimization ToolboxGlobal Optimization ToolboxNeural Network ToolboxModel-Based Calibration Toolbox

Math, Statistics, and OptimizationControl System ToolboxSystem Identification ToolboxFuzzy Logic Toolbox

Robust Control ToolboxModel Predictive Control ToolboxAerospace Toolbox

Control System Design and Analysis Signal Processing ToolboxDSP System ToolboxCommunications System ToolboxWavelet Toolbox

Fixed-Point ToolboxRF ToolboxPhased Array System Toolbox

Signal Processing and Communications

Image Processing ToolboxComputer Vision System ToolboxImage Acquisition ToolboxMapping Toolbox

Image Processing and Computer Vision

Data Acquisition ToolboxInstrument Control ToolboxImage Acquisition ToolboxOPC ToolboxVehicle Network Toolbox

Test and Measurement

Financial ToolboxEconometrics

ToolboxDatafeed ToolboxDatabase Toolbox

Computational FinanceSpreadsheet Link EX (for Microsoft Excel)

Fixed-Income ToolboxFinancial Derivatives Toolbox

Bioinformatics Toolbox

SimBiology

Computational BiologyMATLAB Coder

HDL CoderHDL Verifier

Filter Design HDL Coder

Code Generation and Verification

MATLAB CompilerMATLAB Builder NE (for Microsoft .NET

Framework)MATLAB Builder JA (for Java language)

MATLAB Builder EX (for Microsoft Excel)Spreadsheet Link EX (for Microsoft Excel)

Application DeploymentDatabase Toolbox

MATLAB Report Generator

Database Connectivity and Reporting


1. Simulink

2. Simpowersystems

3. Aerospace Simulation

4. Neural Network

5. Parallel Computing

6. Image Acquisition

7. Image processing

8. Genetic Algorithm

9. Fuzzy Logic

10. Database processing

11. Video and Image processing

12. Control System

13. Signal Processing

14. Statistics

15. Financial Toolbox

16. Curve fitting

.

.

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Toolboxes provided By MATLAB

Faculty of Engineering, Cairo UniversityDr. Mostafa Elshahed

5

Agenda

Introducing MATLAB – Language of technical computing

Minimal MATLAB


Agenda


Minimal MATLAB

MATLAB Desktop

Computing with MATLAB

Array – creation & working

Plotting – creating & visualizing

Automating commands – creating, saving & executing script file

Conditional control statements

Loop control statements

Functions – creating & executing a function file


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Agenda


Minimal MATLAB

MATLAB Desktop









The main window characterized by the MATLAB command prompt (>>)

Command Window

This is where you write, edit, create, and save your own script or programs in files called m-files.

Editor Window

This is where all your files from the current directory are listed.

Current Directory

All commands typed on MATLAB prompt in the command window get recorded, even across multiple session in this window.

Command History

This subwindow lists all variables that you have generated so far along with there type and size.

Workspace

MATLAB - Desktop


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MATLAB - Desktop

The main window characterized by the MATLAB command prompt (>>)

Help Window


Scripts (MATLAB m files)


Scripts are:

collection of commands executed in sequencewritten in the MATLAB editorsaved as MATLAB files (.m extension

To create an MATLAB file

from command-line »edit mostafa.mor click

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Scripts (MATLAB m files)


RUN

Agenda


Minimal MATLAB

MATLAB Desktop









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Arithmetic Operator & Their Precedence

Operations Operators Examples

AdditionSubtractionMultiplicationRight DivisionLeft DivisionExponentiation

Precedence Order

Operators

1

234

Parentheses ( ). For nested parentheses, the innermost are executed first.Exponentiation, ^Multiplication, *; Division, /,\Addition, +; Subtraction, -

help precedence


Mathematical Functions

Trigonometry

sindcosdtandcotdsecdcscd

Degree

sincostancotseccsc

sinhcoshtanhcothsechcsch

asinacosatanacotasecacsc

Basic Hyperbolic Inverse

Radian

Basic

Exponential

exploglog10log2sqrt

Complex

absconjimagrealangle

Matrix

dettracerankinvexpmsqrtm

help <type function name>


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Predefined Variables and Keywords

ans

pieps

infi,jNaN

Predefined Variables

break case catch classdef continue else elseif end forfunction global if otherwise parfor persistent returnspmd switch try while

Keywords

iskeyword

help <Predefined Variable Name>

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iskeyword(‘keyword’) 1 or 0

lookfor keyword


Useful CommandsThe two commands used most by Matlab users are:

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>>help functionname >>lookfor keyword

clc Clears the command window; Semicolon suppresses screen printing

or denotes a new row in an array, Comma or Space separates elements

in a row: Colon generates an array having

regularly spaced elements


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Agenda


Minimal MATLAB

MATLAB Desktop


Vector and Array – creation & working







• No need for types. i.e.,

• All variables are created with double precision unless specified and they are matrices.

• After these statements, the variables are 1x1 matrices with double precision.

int a;double b;float c;

>>x=5;>>x1=2;

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Variables


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Use meaningful names for variables

MATLAB variable names

– must begin with a letter

– can contain any combination of letters, numbers and underscore (_)

– must be unique in the first 31 characters

MATLAB is case sensitive: “name”, “Name” and “NAME” are considered different variables.

Never use a variable with the same name as a MATLAB command.

Naming convention: use lowercase letters

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Variables


Managing Variables

clearclear x y zclear allwhowhos

save

load

Clears the workspace, all variables are removed from memoryClears only variables x, y, and zClears all variables and functions from workspaceLists variables currently in the workspaceLists variables currently in the workspace with their sizes together with information about their bytes and classSave workspace variables to MAT-file >>save(‘MOSTAFA’) MOSTAFA.mat>>save matlab.matLoad data from MAT-file into workspace>>load(‘MOSTAFA’)

Command Outcome


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Overview

5

5745 7 4

5 10 566 4 67 78 86

Scalar of 1 X 1 Row Vector of 1 X 3 Column vector of 3 X 1

One Dimensional Matrix of 3 X 3

5 10 56 85 236 4 6 23 27 78 86 53 6

5 14 12 10 566 10 504 4 6

89 0 0

Two Dimensional Matrix of 3 X 5

3X5X2

5 10 56 85 236 4 6 23 27 78 86 53 6

5 14 12 10 5660

5 14 12 10 56890

Three Dimensional Matrix of 3 X 5

3X5X3


Creation

One Dimensional Array

variable_name = [ type vector elements ]

Two Dimensional Array

variable_name = [1st row elements; 2nd row elements; 3rd row elements; ... ; last row elements]

from a known list of numbers with constant spacing by specifying the first term, the spacing,

and the last term

Known lists of numbers


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Creation

Creating a vector with constant spacing by specifying the first term, the spacing, and the last term:

variable_name = [m:q:n]

or

variable_name = m:q:n

m = first term

q = spacing

n = last term

: (colon operator)Constant spacing

Creating a vector with linear (equal) spacing by specifying the first and last terms, and the number of terms:

variable_name = linspace(xi, xf, n)

xi = first element

xf = Last element

n = number of elements

linspaceConstant spacing


• a vector x = [1 2 5 1]

x =1 2 5 1

• a matrix X = [1 2 3; 5 1 4; 3 2 -1]

X =1 2 35 1 43 2 -1

• transpose y = x’ y =

1251

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Creation


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>> x = [1 2]; y = [4 5]; z=[ 0 0]

>> A = [ x y]

1 2 4 5

>> B = [x ; y]

1 2

4 5

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C = [x y ;z] Error:??? Error using ==> vertcat CAT arguments dimensions are not consistent.


Creation

Array Operators

+ Addition- Subtraction* Multiplication/ Division\ Left Division.* Element-by-element multiplication./ Element-by-element division.\ Element-by-element left division.^ Element-by-element power‘ Transpose

Operations Operation


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Address vector

>> ve = [35 46 78 23 5 14 81 3 55]

ve =

35 46 78 23 5 14 81 3 551 2 3 4 5 6 7 8 9

position or index of element

Data Manipulation


Addressing vector : (colon operator)

Data Manipulation

Addressing matrix : (colon operator)

A(:,n) Refers to the elements in all the rows of column n of the matrix A.

A(n,:) Refers to the elements in all the columns of row n of the matrix A.

A(:,m:n) Refers to the elements in all the rows between columns m and n of the matrix A.

A(m:n,:) Refers to the elements in all the columns between rows m and n of the matrix A.

A(m:n,p:q)Refers to the elements in rows m through n and columns p through q of the matrix A.


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Address

Data Manipulation


• The matrix indices begin from 1 (not 0 (as in C))• The matrix indices must be positive integer

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Given:

A(-2), A(0)

Error: ??? Subscript indices must either be real positive integers or logicals.

A(4,2)Error: ??? Index exceeds matrix dimensions.


Data Manipulation

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Comment used in MATLAB • “%” is the neglect sign for MATLAB (equivalent of “//”

in C). Anything after it on the same line is neglected by MATLAB compiler.

• Sometimes slowing down the execution is done deliberately for observation purposes. You can use the command “pause” for this purpose

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>>pause %wait until any key>>pause(3) %wait 3 seconds


• sort

• sortrows

• issorted 1 or 0

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For vectors, SORT(X) sorts the elements of X in ascending order.For matrices, SORT(X) sorts each column of X in ascending order.

>> x= 1:5x =

1 2 3 4 5>> sort(x)ans =

1 2 3 4 5>> sort(x,'descend')ans =

5 4 3 2 1


Built in Functions

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Limit and Integration


Differentiation


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Initializing with Built-in Functions

zeros(n)

zeros(n,m)

ones(n)

ones(n,m)

ones(size(array))

eye(n)

eye(n,m)

length(vector)

Length(array)

size(array)

zeros(size(array))


Generating Vectors from functions• zeros(M,N) MxN matrix of zeros

• ones(M,N) MxN matrix of ones

• rand(M,N) MxN matrix of uniformly distributed random

numbers on (0,1)

x = zeros(1,3)

x =

0 0 0

x = ones(1,3)

x =

1 1 1

x = rand(1,3)

x =

0.9501 0.2311 0.6068


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Matrices Operations

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Given A and B:

Addition Subtraction Product Transpose


The use of “.” – “Element” Operation

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K= x^2Error:??? Error using ==> mpower Matrix must be square.B=x*yError:??? Error using ==> mtimes Inner matrix dimensions must agree.

A = [1 2 3; 5 1 4; 3 4 -1]A =

1 2 35 1 43 4 -1

y = A(3 ,:)

y= 3 4 -1

b = x .* y

b=3 8 -3

c = x . / y

c= 0.33 0.5 -3

d = x .^2

d= 1 4 9

x = A(1,:)

x=1 2 3


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Matrix Operation(cont…)

• transpose(‘)

• tril: lower triangular matrix

• triu: upper triangular matrix

• rank: show rank of matrix

• det: determinant of matrix

• diag: returns principle diagonal

• inv: inverse of the matrix

• eig: eign value(matrix must be square matrix)


Displaying Data/Text


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Displaying Data/Text(cont…)


Thank You…


Documents

Introduction to MATLAB - Cairo Universityscholar.cu.edu.eg/?q=mostafa_elshahed/files/lec_1_0.pdf · Introduction to MATLAB (MATrixLABoratory) ... Final Exam 30 Grades----- Total Grade