MATLAB – Loops

MATLAB stands for Matrix Laboratory. It is a high-performance language that is used for technical computing. It was developed by Cleve Molar of the company MathWorks.Inc in the year 1984.It is written in C, C++, Java. It allows matrix manipulations, plotting of functions, implementation of algorithms and creation of user interfaces.

• While Loop: While loop works same as it does in other common languages like python, java etc. But here syntax varies from language to language. While loop is used to execute a block of statements repeatedly until a given a condition is satisfied. And when the condition becomes false, the line immediately after the loop in program is executed.

Syntax:

while expression
    statements
end

Example 1:

Matlab

%MATLAB code to illustrate

%for loop

count=0;

while (count < 3)

   fprintf('Hello From GeekforGeeks\n');

   count=count+1;

end

Output:

Hello From GeekforGeeks
Hello From GeekforGeeks
Hello From GeekforGeeks

• For Loop: For loops are used for sequential traversal. As syntax varies from language to language. Let us learn how to use for loop for sequential traversals.

Syntax:

for initial value:step value:final value
   statements
end

or

for initial value:final value   
   statements 
end 

Example 2

Matlab

%MATLAB code to illustrate

%for loop

for i = 1:5

   fprintf('%d ',i)

end

Output:

1 2 3 4 5

Example 3

Matlab

%MATLAB code to illustrate

%for loop

for i = 1:2:5

   fprintf('%d ',i)

end

Output:

1 3 5

We have one more way of using for loop, that is used to access array elements. Here we assign an array directly to the for loop to access its elements through the iterator variable (i.e., i or j etc).

Example 4

Matlab

%for iterator_variable = array

for i =[1 2 3 4]

   fprintf('%d ',i)

end

Output:

1 2 3 4

Iterating through strings is same as iterating through a range of numbers. Here we use length() function to provide final value in for loop, and we can also use disp() function to print the output.

Example 5

Matlab

%MATLAB code to illustrate

%how to iterate through strings

String = 'GeeksforGeeks'

for i = 1:length(String)

   fprintf('%c ',String(i))

   %disp(String(i))

end

Output:

G e e k s f o r G e e k s