1. Matlab Basic Dr. Imtiaz Hussain
Assistant Professor
URL :

2. Contents What is MATLAB? Basic commands Variable definition
Introduction to Matlab
Matlab system
MATLAB Product Family
Toolboxes
SIMULINK
Basic commands
Entering and quitting Matlab
MATLAB Desktop
Other basic commands
Variable definition
Defining Scalars in MATLAB
Defining Vectors in MATLAB
Defining Matrices in MATLAB
Defining character arrays

3. Introduction to MATLAB

4. Introduction to MATLAB
Integrated software environment
Math and Computation
Algorithm Development
Modeling
Simulation
Visualization
Analysis
Scientific and engineering graphics
Application Development
GUI development
Easy-to-use environment

5. The MATLAB System MATLAB System Handle graphics
MATLAB language
MATLAB working Environment
Handle graphics
MATLAB mathematical function library
MATLAB application program interface (API)

6. MATLAB Language
This is a high level matrix/array language with following features.
Control flow statements
Functions
Data structures
Input/output
Object oriented programming features

7. MATLAB working Environment
This is the set of tools and facilities that you work with as MATLAB user or programmer.
It Includes the tools and facilities of
Managing the variables
Importing and exporting data
Developing, managing and debugging M-files

8. Handle Graphics
This is the MATLAB graphic system. It includes high level commands for:
2-D data visualization
3-D data visualization
Image processing
Animations
Presentation graphics
GUI tools

9. MATLAB mathematical function Library
This is vast collection of computational algorithms like:
Sum
Sine
cosine
Complex arithmetic
Matrices and inverses
Matrix Eigen values
Bessel functions
FFT
And many others

10. Application Program Interface (API)
This is the library that allows you to write C and Fortran programs that interact with MATLAB. It includes facilities for:
Calling routines from MATLAB
Calling MATLAB as a computational engine
Reading and writing MAT files.

11. MATLAB Product Family MATLAB MATLAB Extensions MATLAB Compiler
SIMULINK Extensions
Real Time Workshop
Blocksets
DSP
Control System
Communications
e.t.c
MATLAB
SIMULINK
MATLAB Extensions
MATLAB Compiler
MATLAB C Math Library
Toolboxes
Communication
Financial
Fuzzy Logic
Image Processing
Neural Networks
Optimization
Signal Processing

12. Basic Commands

13. Entering & Quitting MATLAB
To enter MATLAB double click on the MATLAB icon.
To Leave MATLAB Simply type quit and press enter.
>> quit

14. MATLAB Desktop

15. Some Basic Commands >>ver >>clc >>home
To check the list of installed toolboxes type
>>ver
To clear the screen type
>>clc
To move the cursor to upper left corner of the command window type
>>home

16. Some Basic Commands (contd…)
To list the current variables type
>>who
To list the current variables in long form type
>>whos
To clear the workspace type
>>clear
To remove particular variable from the workspace type
>> clear ‘name of the variable’

17. Some Basic Commands (contd…)
To get list of Help topics type
>>help
To get help for any topic type
>>help ‘topic’
To get help for any command type
>>help ‘command/syntax’

18. Some Basic Commands (contd…)
To search command type
>>lookfor ‘keyword’
To list the files in a directory type
>>dir ‘directory name’
To list the Matlab files only type
>>what ‘directory name’

19. Working With MATLAB Variables

20. Types of MATLAB Variables
Scalar
1x1 array
Vector
nx1 (column vector) or 1xn (row vector)
Matrix
mxn
Character Arrays (Strings)

21. Defining Scalars >> a = 2 a = 2
Variables are assigned numerical values by typing the expression directly, for example, typing
>> a = 2
yields:
a = 2

22. Variable Definitions
We can also assign numerical values to the variables by typing the expression >> b = 1+2 yields: b = 3

23. Variable Definitions
After typing the expressions the answers are echoed back.
To suppress the echo put semicolon at the end of the expression.
>> c = 5;

24. Arithmetic Operators on Scalars
MATLAB utilizes the following arithmetic operators:  +
 Addition  -
 Subtraction  *
 Multiplication  /
 Division  ^
 Power Operator

25. Variable Definition (Contd…….)
A variable can be assigned using a formula. For example, since a was defined previously, the following expression is valid
>> d = 2*a
yields:
d = 4

26. Variables in Workspace
Type who to check the stored variables in workspace.
>> who
Your variables are:
a b c d

27. Variables in Workspace
Type whos to check the stored variables in long form.
>> whos
Name Size Bytes Class
a x double array
b x double array
c x double array
d x double array
Grand total is 4 elements using 32 bytes

28. Complex numbers
A complex number 3+2i in Matlab is entered in the following form
>> 3+2*i Or
>> 3+2*j

29. Complex numbers >> 3e-2 Yields: ans= 0.0300
An exponential number 3x10-2 in Matlab is entered in the following form
>> 3e-2
Yields:
ans=
0.0300

30. Exercise#1
Investigate the effect of following commands
(i) k= (ii) f= 2*c/ (iii) g=c*d^ (iv) h=c-d+k (v) who (vi) whos
(vii) clear (viii) who (ix) whos
(x) 3x10-5+5j

31. Defining Vectors
Row Vectors
1xn
Column Vectors
nx1

32. Defining Row Vectors To create a row vector A simply type in:
1x9 vector
A = 2 4 7 1 5 6 1 2 3 4 5 6 7 8 9
A(2)
A(5)

33. Defining Row Vectors v = [2 0 1 4 7 1 5 6 4] A = A(1:4) A(6:9) 2 4 7 1
1x9 vector
A = 2 4 7 1 5 6 1 2 3 4 5 6 7 8 9
A(1:4)
A(6:9)

34. Defining Column Vectors
To create a column vector B simply type in:
B = [3; 5; 0; 0; 1; 4; 9; -1; 1] 1 -1 9 4 5 3 2 6 7 8
B(3)
B =
9x1 vector
B(5)

35. Defining Column Vectors
B = [3; 5; 0; 0; 1; 4; 9; -1; 1] 1 -1 9 4 5 3 2 6 7 8
B(2:5)
B =
9x1 vector
B(7:9)

36. Arithmetic Operators (Arrays) +
Addition  -
Subtraction
 .*
Array multiplication
 ./
Array division
 .^
Array power operator  '
transpose

37. Exercise#2
Investigate the effect of the following commands:
V=[ ] and w=[ ]
(i) v(2) (ii) sum = v + w (iii) diff = v – w (iv) vw = [v w] (v) vw(2: 6) (vi) v’
(vii) v./w (viii) v.*w (ix) whos

38. Exercise#3 (i) z’ (ii) z*v (iii) [v; w] (iv) v*z
Investigate the effect of the following commands.
z=[1; 1; 0; 0]
(i) z’ (ii) z*v
(iii) [v; w] (iv) v*z
(v) [z; v’] (vi) z + v’

39. Defining Matrices
A Matrix is a mxn array

40. Defining Matrices The most obvious ways are to type M = [1 2; 3 4] or
To enter the matrix
The most obvious ways are to type
M = [1 2; 3 4] or
M = [ [1 3]’ [3 4]’ ]

41. Defining Matrices
N=[ ; ; ; ]
N(1,3) or N(9) 1 3 9 7 4 8 2 5 6 10 11 12 14 15 16 13
N =
N(4,3) or N(12)

42. Defining Matrices
N=[ ; ; ; ]
N(1:4) 1 3 9 7 4 8 2 5 6 10 11 12 14 15 16 13
N =
N(10:12)

43. Defining Matrices 1 3 9 7 4 8 N = N(1:2,1:2) N(3:4,3:4) 2 5 6 10 11 122 5 6 10 11 12 14 15 16 13
N =
N(3:4,3:4)

44. Defining Matrices
N(:,1:2) 1 3 9 7 4 8 2 5 6 10 11 12 14 15 16 13
N =

45. Defining Matrices 1 3 9 7 4 8 2 5 6 10 11 12 14 15 16 13
N =
N(3:4,:)

46. Exercise#4 (i) N’ (ii) M*N (iii) M/N
Investigate the effect of the following commands:
M=[1 2; ]
N=[ ; ]
(i) N’ (ii) M*N (iii) M/N
(iv) M + N (v) M*z(1:2) (vi) v(3:4)*M
(vii) M(1,1) (viii) M(1:2,1:2) (ix) M(:,1)
(x) M(2,:)

47. Exercise#5 (i) K = inv(M) (ii) I = eye(2) (iii) rank(M)
Investigate the effect of the following commands:
M=[1 2; ]
(i) K = inv(M) (ii) I = eye(2) (iii) rank(M)
(iv) Zeros(3) (v) Zeros(3,2) (vi) ones(4)
(vii) ones(4,5) (viii) tril(M) (ix) triu(M)
(x) diag(M) (xi) size(M) (xii) det(M)
(xiii) eig(M) (xiv) magic(3)

48. Exercise#6
Define a matrix A of dimension 2 x 4 whose (i,j) entry is A(i,j)=i+j
Extract two 2 x 2 matrices A1 and A2 out of the matrix A. A1 contains the first two columns of A, A2 contains the last two columns of A
Compute the matrix B to be the sum of A1 and A2
Compute the eigen values and eigen vectors of B
Compute the determinant of B
Compute the inverse of B
Compute the rank of B

49. Defining Character Arrays (Strings)
Character arrays are created using single quote delimiter
>> str = ‘MATLAB‘
Yields
str =
MATLAB
1x6 vector
str = M A L B T 1 2 3 4 5 6

50. Defining Character Arrays (Strings)
>> str = ‘MATLAB‘
str = M A L B T 1 2 3 4 5 6
str(5:6)
str(3)

51. Conversion B/W Numeric & String Arrays
To convert from numeric to string array
num2str
To convert from string array to numeric array
str2num

52. Numeric to string conversion
>> strnum=num2str(num);
>> whos
Name Size Bytes Class
strnum x char array
num x double array
Grand total is 4 elements using 14 bytes

53. String to Numeric conversion
>> num=str2num(str);
>> whos
Name Size Bytes Class
num x double array
str x char array
Grand total is 5 elements using 16 bytes

54. Thank you for your concentration
Questions