This document covers basic MATLAB commands, operators, and branching statements. It includes inputting and displaying variables, relational operators like equality and inequality, logical operators like AND and OR, and conditional statements like if/else and try/catch. Functions like input, disp, factorial and logical operators are demonstrated with examples to calculate the factorial of the difference between two user-input numbers.

1. Matlab basics ,operators &
branching statements

2. Basics commands
• Inputting a variable
Num = input(‘ Enter a number ’);
• Displaying output data
– Use of semicolon
– X=a+b;
– X=a+b  output displays automatically
• disp(‘Hello’)

3. Relational operators
• Equality ==
• Not equal ~=
• >
• <
• >=
• <=

4. Equality operator ==
• Difference between ‘=‘ & ‘==‘
• A=5; B=5; C=-35;
• A==B  1
• A==C 0
• Q=[1 2 3]; W=[2 3 4] ; R=[1 9 3] ; T=[1 2 3];
• Q==W  ?
• Q==T  ?
• Use of isequal()

5. Not equality ~=
• A=89;
• B=79;
• C=89;
• A==B  ??
• A~=B  ??
• A~=C  ??

6. > ,< , >= ,<=
• A=12 ; B=87 ; C=78;
• A>B
• A<B
• Q=[1 2 3 8 9 4] R=[2 3 1 8 9 2]
• Q>R
• Q<R

7. Logic operators
• Logical AND &
• Logical AND with shortcut evaluation &&
• Logical OR |
• Logical OR with shortcut evaluation ||
• Logical XOR xor(a,b)
• Logical NOT ~

8. Logical AND &
0 0 ?
0 1 ?
1 0 ?
1 1 ?
Truth table
a b Y=a & b
0 0 0
0 1 0
1 0 0
1 1 1
A = 1;
B=0;
A & B  ?
A=8;
B=-9;
A & B ?

9. Logical AND with shortcut evaluation
&&
• Support partial evaluations
• A = 0 ;
• B= 1;
• A & B 
• A && B 

10. Problem
• Test whether ratio of two variables a and b is
greater than 10
• X = a/b >10 ;
• What if b = 0?
• Use shortcut evaluations
• x = (b ~= 0) && (a/b > 10)

11. Logical OR |
a b Y=a |b
0 0 ?
0 1 ?
1 0 ?
1 1 ?
Truth table
a b Y=a | b
0 0 1
0 1 1
1 0 1
1 1 0
A = 1;
B=0;
A | B  ?
A=8;
B=-9;
A | B ?

12. Logical XOR xor(a,b)
a b Y= xor ( a ,b)
0 0 ?
0 1 ?
1 0 ?
1 1 ?
Truth table
a b Y=xor ( a , b)
0 0 0
0 1 1
1 0 1
1 1 0
A = 1;
B=0;
xor ( A , B)  ?
A=8;
B=-9;
xor ( A, B) ?

13. Logical NOT ~
• One operand only
• A=1;
~A  ??
• B= false
~B  ??
• C=-89
~C  ??

14. Logical functions
• isequal(a,b)
• ischar(a)
• isempty(a)
• isinf(a)
• isnan(a)
• isnumeric(a)
• logical(a)

15. A=‘brainbitz’; C=-89; D=[1 2 -3 0 1 ];
B=15; E =[ ]; F=0;
H = [1 2 3 4]; J=[1 2 3] ; G =[ 0 0 0];
• ischar(A)
• ischar(C)
• isempty(F)
• isempty(E )
• isempty(G)
• isinf(C)
• isinf(C/F)
• isnumeric(D)
• logical (D)  [1 1 1 0 1];

16. Branching statements & Loops
• If
• Switch
• While
• For
• Try catch branch

17. If statement
if (condition 1)
---------------
----------------
elseif (condition 2)
---------------
---------------
else
-----------
----------
end

18. Switch
switch (expression)
case val1
----------
----------
case val2
--------
-------
otherwise
---------
----------
end

19. while
while (expression)
------------------
------------------
end

20. For
for index=1:increment:m
------------------
-----------------
end

21. Try/catch
try
--------------
--------------
catch
---------------
---------------
end

22. Problem
• Input 2 numbers and calculate factorial of their
differences , ie (N1 – N2)!
N1=input(‘Enter number 1 ‘);
N2=input(‘Enter number 2 ’ );
Result = factorial(N1 – N2);
Outputs
N1=5 ;
N2=2;
Result =3!
=6
N1=2;
N2=5;
Result = -3 !
= ERROR !!!

23. Continued…
N1=input(‘Enter number 1’);
N2=input(‘Enter Number 2’);
try
Result = factorial( N1 - N2 );
catch
Result = factorial( N2 - N1 );
end