this is an powerful intro to MATLAB Programming. I hope it to be useful to all of you :) .

1. MATLAB
Programming
By : Ahmed Moawad

2. LET’S BEGIN……
MATLAB is a tool that simplify the programming than
any other programming language like c , c# , …….
Let’s begin with first function in MATLAB …
And the most helpful Fn .
>> help ;
this function gives you a very useful tutorial ,
and information about using MATLAB in every
applications.
1

3. FIRST TIME : HOW TO INPUT A MATRIX OR
VECTOR IN MATLAB

Vector :
>> x = [1 2 3 4]
x=1
2
3
4
o Matrix :
>> y = [1 2 3 ; 5 1 4 ; 2 3 1]
y=1
2
3
5
1
4
2
3
1
2

4. CHARACTERISTICS OF MATRIX
Transpose :
>> xt = x ’
convert the columns to rows and vice versa
x=1
2
3
4
 >> x = [1 : 5]
x=1 2 3 4 5
this is the step of increment
 >>x = [1 : 2 : 5]
x=1 3 5

3

5. CONTINUE……
>>size (y)
Number of columns and rows
 >>length(y)
The tallest dimension(row , column) of Matrix
1
 >>z = y( 2 , 2:3 )
Choose the second & third columns.
5
z=1 4
Choose the second row.
 >>zeros(M ,N);
Matrix consists of zeros
 >>ones(M,N);
Matrix consists of ones
 >>eye(M,N) ;
The main diameter of Matrix is ones , others zeros
 >>rand (M,N) ;
Uniform Distribution
 >>randn (M,N);
Normally Disribution

4

6. OPERATORS
Scalar Arithmetic Operations :
>> z = x * y; multiply every element in x to its corresponding in y.

Matrices Arithmetic Operations:
>> z = x .* y ; multiply as matrices rules ,with condition (Num. of rows

of x = Num. of columns of y)
+
.+
Summation
-
.-
Subtraction
/
./
Division
^
.^
Exponential
5

7. FUNCTIONS BREAK (1):

>>sign(x) ;
If an element in matrix x is +ve returns 1 ,-ve returns
-1.
>>exp (2) The exponential function.
ans = 7.3891
 round (x); Approximate the number x to the nearest number
 Fix (x) ;
Delete the fraction (1.2>>1, 1.6 >>1)
 Abs(complex ); Magnitude of complex number
 Angle(comp.); Angle of complex number
 Real(complex); Real part of complex.
 isprime(x) ; 0 for not , 1 for prime number

6

8. FLOW CONTROL FUNCTIONS
For loop:
i.e.:
>>a=3;
initial value of b
>>for i = 1 :1: 10;
initial : step : final
a=a +i;
end
>> disp(a);
Fn. that display the value of a
>>sprintf (‘the number of icons is = %g ’ , a)

print the sentence ‘ ’ , replaces the %g by a
7

9. .
CONTINUE …
While loop:
i.e.:
>>b =0;
initial value of b
>>while b<4
carry out if b <4 , stop if else
b=b+1;
end
>>weight = b*2.2;
>>disp(b);
>>sprintf(‘The weight equals %f ’ , weight)

weight is float type
8

10. ..
CONTINUE …
If Statement:
i.e.:

degree =input(‘please insert the degree(0-100): ’)
fn. that make user input the value which preferred
if degree>= 85
disp(‘Excellent’)
elseif( degree>= 75 & degree <85)
disp(‘very good’)
elseif( degree>= 65 & degree <75)
disp(‘good’)
elseif( degree>= 50 & degree <65)
disp(‘pass’)
else
disp(‘fail’)
end
9

11. …
CONTINUE …
Switch …case:
i.e.:
month= input (‘please input the month(1-12): ’)
switch month
case { 1,3,5,7,8,10,12} more than one case>> {1,2,…..}
disp (31)
case{4 , 6 ,9 ,11}
disp (30)
case 2
only one case>> 1
disp (28)
end

10

12. FUNCTION BREAK(2):
>>Str = ‘ the sentence you want to write’
 >>w = str [ 1 2 5 7 9]
w = thsne
 x(2) = 4
change the second element value in the matrix x to 4.
 X(3) = [ ]
delete the third element .
 mean(x)
The mean of elements of x .
 std(x)
The standard diversion of elements of x.
 [theta phi r ] = cart2sph [2 , 3 , 5]

any names indicates the sph.
Conversion fn.
the values of Cartesian coordinates
11

13. GRAPHS
Line plot :
i.e.:
>>t = [ 0 : 10 ];
>> y = sin(t);
>>Figure(1)
>>plot (t,y)
>>xlabel(‘time’)
>>ylabel(‘input’)
>>title (‘Gain’)

y is sinusoidal wave on t
Open figure , name it 1
plot t(h-axis) versus y (v-axis) in figure.
write 9time) under h-axis
write (input) beside v-axis
Make a title for plot
12

14. .
CONTINUE …
Bar Graph:
i.e.:
>>x = -3 : 1 : 3;
>>y = x.^2;
>>bar(x,y)
Bar Graph
>>figure(1)
>>subplot 221
divide the figure into number of plots
>>z= magic (3);
special function
>>subplot 222
row no. column no. position
>>bar(z)
>>subplot (2,2,3)
>> bar(z , ‘grouped’) Style type
>>subplot(2,2,4)
>>bar (z , ‘stacked’)

13

15. ..
CONTINUE …
Histogram :
>> hist (z , 7 )

Number of intervals in histogram
Pie Graph :
>>z = [10 4 5 8 2];
>>pie(z)

Polar Graph :
>>polar(t , y)

14

16. …
CONTINUE …
Scatter plot :
>>x =[1:10];
>> y = 2.*rand (1,10)
>>subplot 221
>>scatter(x ,y)
scatter points on plot
>>subplot 222
>> stem ( x , y)
scatter points connected with the h-axis
>>subplot 223
>>scatter(x ,y , 3 , ‘y’ ) Mark color (yellow)

size of mark (scatter point)
15

17. ….
CONTINUE …
Pie graph
scatter graph
Polar graph
Bar graph
Histogram
16

18. FUNCTION BREAK(3)
>>log (x)
 >>log10(x)
 >>log2 (x)
 >>semilogy(x,y)
 >>semilogx(x,y)
 >>loglog(x,y)
 >>barh(z)
 >>break;
 >>continue;
 >>surf(x,y,z)
 >>contour(x,y,z)

Ln Function
Log. Decimal Function
Log. Binary Function
convert v-axis to dB
convert h-axis to dB
convert two axes to dB
Opposite of Bar graph
stop loop and move to the next command
stop the itertion and move to the other itertion on loop
Graph the surface and put the points on it
17

19. SYMBOLIC MATH :

Functions:

>>syms x y z ;
convert this variables into symbols
>>f = x^2 + y^2 +z^2;
Substitution
the symbols you want substitute
>>f1 = subs( f , [x y] , [4 5] )
the values of substitution
f1 = 16 + 25+z^2
Differentiation
>>f2 = diff ( f , 2 , z )
The symbol you want to diff.
f2 = 2
The order of diff.
Integration
>>f3 = int (f1 , -10 , 10 )
Final limit
f3 = 5
initial limit
Limit Fn
>>limit ( sin (x) /x , inf )
the value the limit approximate to
Summation
>>symsum( 1 / x^2 , 1 , inf )
the final sub . of summation
the initial sub. of summation
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20. DOMAINS TRANSFORMS :
Laplace Transform :
>>syms t ;
>> laplace ( cos (t))
laplace transform
Ans = s / (s^2 +1)
>>ilaplace (s/ (s^2 +1)
inverse laplace transform
Ans = cos t
>>transferfn = tf ([1] , [1 2 1]) transfer fn.
Transfer function = 1 / s^2 + 2* s + 1
>> bode(transferfn)
Bode plot
>> step(transferfn)
Step response
>> impulse (transferfn)
Impulse response

19

21. .
CONTINUE …
Fourier Transform :
>>syms t w b ;
>>y = cos(b*t);
>> f = fourier (x , t ,w );
>>y = cos( 2*pi *t);
>>fd = fft ( y , 512 );
must be 2^n

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22. THANK YOU