Matlab Basic
MATLAB Product Family
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Entering & Quitting MATLAB
• To enter MATLAB double click on the MATLAB icon.
• To Leave MATLAB Simply type quit and press enter.
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Some Basic Commands
• To check the list of installed toolboxes type
• To clear the screen type
• To move the cursor to upper left corner of the command window type
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Some Basic Commands (contd…)
• To list the current variables type
• To list the current variables in long form type
• To clear the workspace type
• To remove particular variable from the workspace type
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Some Basic Commands (contd…)
• To get list of Help topics type
• To get help for any topic type
• To get help for any command type
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Some Basic Commands (contd…)
• To search command type
• To list the files in a directory type
• To list the Matlab files only type
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Types of MATLAB Variables
• Scalar
array
• Vector
(column vector) or
•
Matrix
•
Character Arrays (Strings)
(row vector)
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Defining Scalars
Variables are assigned numerical values by
typing the expression directly, for example,
typing
yields:
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Variable Definitions
We can also assign numerical values to the variables
by typing the expression
yields:
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Variable Definitions
• After typing the expressions the answers are
echoed back.
• To suppress the echo put semicolon at the end
of the expression.
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Arithmetic Operators on Scalars
• MATLAB utilizes the following arithmetic operators:
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Variable Definition (Contd…….)
A variable can be assigned using a formula. For example,
since a was defined previously, the following expression is
valid
yields:
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Variables in Workspace
• Type who to check the stored variables in workspace.
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Variables in Workspace
• Type whos to check the stored variables in long form.
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Complex numbers
• A complex number 3+2i in Matlab is entered in the
following form
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Complex numbers
• An exponential number 3x10-2 in Matlab is entered in the
following form
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Exercise#1
Investigate the effect of following commands
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Defining Vectors
• Row Vectors
A  a1 a2 ... an 
• Column Vectors
 b1 
b 
 2
. 

B   
.
 
 . 

bn 

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Defining Row Vectors
To create a row vector A simply type in:
A = [2
1
A(2)
2
0 1
3
4
4
5
7
6
1
5
7
8
6
4]
9
A(5)
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Defining Row Vectors
v = [2
1
0 1
2
A(1:4)
3
4 7
4
5
1
6
7
5
6
8
9
4]
A(6:9)
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Defining Column Vectors
To create a column vector B simply type in:
B = [3; 5; 0; 0; 1;
4;
9; -1;
1]
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B =
B(3)
03
04
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9x1 vector
97
-1 8
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B(5)
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Defining Column Vectors
B = [3; 5; 0; 0; 1;
4;
9; -1;
1]
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B =
03
04
15
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B(2:5)
9x1 vector
97
-1
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B(7:9)
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Arithmetic Operators (Arrays)
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Exercise#2
Investigate the effect of the following commands:
V=[2 4 7 5]
and
w=[1
3
8
9]
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Exercise#3
Investigate the effect of the following commands.
z=[1; 1; 0; 0]
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Defining Matrices
A Matrix is a mxn array
 a11
a
 21
.

M 
.

 .
am1
a12
a22
.
.
.
am 2
... a1n 

... a2 n 
.
. 
.
. 

.
. 
... amn 
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Defining Matrices
To enter the matrix
1 2
M 

3 4
The most obvious ways are to type
or
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Defining Matrices
N(1,3) or N(9)
N=[1 3 9 1; 2 1 7 4; 7 4 1 8; 1 9 3 0]
1
3
N 
7

1
3 9 1

1 7 4
4 1 8

9 3 0
1 1 3 5 9 9 1 13
N =
32 1
7
6
4
10
14
7 3 4 7 1 11 8 15
1 4 9 8 3 12 0 16
N(4,3) or N(12)
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Defining Matrices
N=[1 3 9 1; 2 1 7 4; 7 4 1 8; 1 9 3 0]
1
3
N 
7

1
3 9 1

1 7 4
4 1 8

9 3 0
N(1:4)
1 1 3 5 9 9 1 13
N =
32 1
7
6
4
10
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7 3 4 7 1 11 8 15
1 4 9 8 3 12 0 16
N(10:12)
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Defining Matrices
N(1:2,1:2)
1
3
N 
7

1
3 9 1

1 7 4
4 1 8

9 3 0
1 1 3 5 9 9 1 13
N =
32 1
7
6
4
10
14
7 3 4 7 1 11 8 15
1 4 9 8 3 12 0 16
N(3:4,3:4)
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Defining Matrices
N(:,1:2)
1
3
N 
7

1
3 9 1

1 7 4
4 1 8

9 3 0
1 1 3 5 9 9 1 13
N =
32 1
7
6
4
10
14
7 3 4 7 1 11 8 15
1 4 9 8 3 12 0 16
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Defining Matrices
1
3
N 
7

1
3 9 1

1 7 4
4 1 8

9 3 0
1 1 3 5 9 9 1 13
N =
32 1
7
6
4
10
14
7 3 4 7 1 11 8 15
1 4 9 8 3 12 0 16
N(3:4,:)
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Exercise#4
Investigate the effect of the following commands:
M=[1 2; 3 4]
N=[-1 3; 5 2]
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Exercise#5
Investigate the effect of the following commands:
M=[1 2; 3 4]
1 2
M 

3 4
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Exercise#6
1)
Define a matrix A of dimension 2 x 4 whose (i,j) entry is A(i,j)=i+j
2)
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
3)
Compute the matrix B to be the sum of A1 and A2
4)
Compute the eigen values and eigen vectors of B
5)
Compute the determinant of B
6)
Compute the inverse of B
7)
Compute the rank of B
Defining Character Arrays (Strings)
Character arrays are created using single quote delimiter
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2
3
4
5
6
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Defining Character Arrays (Strings)
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2
3
4
5
6
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Conversion B/W Numeric & String Arrays
•
To convert from numeric to string array
– num2str
• To convert from string array to numeric array
– str2num
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Numeric to string conversion
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String to Numeric conversion
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Thank you for your concentration
QUESTIONS
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