MATLAB Tutorial

Basic Arithmetic Operations in MATLAB

MATLAB provides a powerful set of tools for performing basic arithmetic operations. These operations are essential for numerical computations and data analysis.

Basic Arithmetic

Arithmetic operations in MATLAB are straightforward and use the standard mathematical operators:


% Basic Arithmetic Operations 

a = 10; 

b = 5; 

sum = a + b;      % Addition 

difference = a - b; % Subtraction 

product = a * b;  % Multiplication 

quotient = a / b; % Division 

remainder = mod(a, b); % Modulus 


disp(sum);        % Output: 15 

disp(difference); % Output: 5 

disp(product);    % Output: 50 

disp(quotient);   % Output: 2 

disp(remainder);  % Output: 0

Explanation: The basic arithmetic operators (+, -, *, /, and mod) allow for simple mathematical computations.

Order of Operations

MATLAB follows the standard order of operations (PEMDAS – Parentheses, Exponents, Multiplication and Division, Addition and Subtraction):


% Order of Operations Example 

result = (3 + 2) * 4^2 / 2; 

disp(result); % Output: 40

Explanation: Parentheses dictate the priority, followed by exponents, then multiplication/division, and finally addition/subtraction.

Matrix Arithmetic

MATLAB excels in matrix computations. You can perform element-wise operations or matrix operations:


% Matrix Arithmetic 

A = [1 2; 3 4]; 

B = [5 6; 7 8]; 


C = A + B;      % Matrix Addition 

D = A - B;      % Matrix Subtraction 

E = A * B;      % Matrix Multiplication 

F = A .* B;     % Element-wise Multiplication 

G = A / B;      % Matrix Division 

H = A ./ B;     % Element-wise Division 


disp(C); disp(D); disp(E); 

disp(F); disp(G); disp(H);

Element-wise Operations

Use a dot (.) before the operator to apply element-wise arithmetic operations.

Special Mathematical Operations

MATLAB includes functions for special operations like power, square root, logarithm, and trigonometry:


% Special Mathematical Operations 

x = 16; 

y = 2; 


square_root = sqrt(x);  % Square root 

power_result = x^y;     % Exponentiation 

log_value = log(x);     % Natural logarithm 

sin_value = sin(pi/2);  % Sine function 


disp(square_root);   % Output: 4 

disp(power_result);  % Output: 256 

disp(log_value);     % Output: ~2.77 

disp(sin_value);     % Output: 1

Common Arithmetic Errors

Be mindful of these common pitfalls:

Division by zero produces Inf or NaN.
Matrix dimensions must agree for matrix operations.

Useful MATLAB Functions

Function

Explanation

sum

If N is 1D array, then TotalSum = sum(N) will displays the sum of all its elements.
If N is 2D array, then TotalSum = sum(N) will output the sum of all the individual columns in a row vector.

prod

If N is 1D array, then A = prod(N) will displays the product of all its elements.
If N is 2D array, then A = prod(N) will output the product of all the individual columns in a row vector.

.*
times

A = N.*M will multiply each element of N to the corresponding element from M.
A = timesr(N,M) is an another way to execute N.*M

.^
power

A = N.^M will output each element of N raised to the element-wise power from M.
A = power(N,M) is an another way to execute N.^M

round

N = round(N) will round all the elements of N to their nearest integer.

Practice Questions

Test Yourself

1. Compute the sum, difference, product, and quotient of 8 and 4 in MATLAB.

2. Perform matrix addition and multiplication for the matrices A = [1 2; 3 4] and B = [5 6; 7 8].

3. Calculate the square root, logarithm, and sine of the value 10.