**Course Title:** MATLAB Programming: Applications in Engineering, Data Science, and Simulation **Section Title:** MATLAB Control Structures **Topic:** Write programs that use control structures to solve practical problems involving decision-making and repetition.(Lab topic) **Introduction** In the previous topics, we learned about basic MATLAB syntax and control structures, including conditional statements and looping structures. In this lab, we will put our knowledge to practice and write programs that use control structures to solve practical problems involving decision-making and repetition. We will explore how to use control structures to solve real-world problems and improve our code's efficiency and readability. **Practical Problem: Grade Calculator** Suppose we want to create a program that calculates a student's grade based on their scores in three subjects: Mathematics, Science, and English. We will use a conditional statement to determine the student's grade based on their average score. ```matlab % Define variables math_score = input('Enter Mathematics score: '); science_score = input('Enter Science score: '); english_score = input('Enter English score: '); % Calculate average score average_score = (math_score + science_score + english_score) / 3; % Use if-else statement to determine grade if average_score >= 90 grade = 'A'; elseif average_score >= 80 grade = 'B'; elseif average_score >= 70 grade = 'C'; elseif average_score >= 60 grade = 'D'; else grade = 'F'; end % Display result fprintf('Your grade is: %s\n', grade); ``` **Practical Problem: Number Series Generator** Suppose we want to create a program that generates a sequence of numbers based on a user's input. We will use a looping structure to generate the sequence. ```matlab % Define variables start_number = input('Enter starting number: '); end_number = input('Enter ending number: '); increment = input('Enter increment: '); % Use for loop to generate sequence for i = start_number:increment:end_number fprintf('%d ', i); end fprintf('\n'); ``` **Practical Problem: Guessing Game** Suppose we want to create a program that plays a guessing game with the user. We will use a while loop to repeatedly ask the user for their guess until they correctly guess the number. ```matlab % Define variables secret_number = randi(100); guesses = 0; % Use while loop to play game while true guess = input('Guess a number between 1 and 100: '); if guess == secret_number fprintf('Congratulations! You guessed the number in %d attempts.\n', guesses); break; elseif guess < secret_number fprintf('Your guess is too low.\n'); else fprintf('Your guess is too high.\n'); end guesses = guesses + 1; end ``` **Key Concepts** * Control structures (if-else, switch-case, for, while, break, continue) can be used to solve practical problems involving decision-making and repetition. * Programs can be written to solve real-world problems using control structures. * Code can be improved by using control structures to reduce repetition and increase efficiency. **Practical Takeaways** * Use if-else statements to make decisions in your code. * Use for loops to repeat a task for a specified number of iterations. * Use while loops to repeat a task until a specified condition is met. * Use break statements to exit a loop when a condition is met. * Use continue statements to skip to the next iteration of a loop. **Recommended Resources** * MATLAB Documentation: Control Structures ([https://www.mathworks.com/help/matlab/control-flow.html](https://www.mathworks.com/help/matlab/control-flow.html)) * MATLAB Tutorial: Control Structures ([https://www.mathworks.com/matlabcentral/fileexchange/34797-control-structures-tutorial](https://www.mathworks.com/matlabcentral/fileexchange/34797-control-structures-tutorial)) **Exercise** 1. Write a program that calculates the factorial of a user-inputted number using a for loop. 2. Write a program that generates a sequence of numbers from 1 to n using a while loop, where n is a user-inputted number. 3. Write a program that plays a game of rock-paper-scissors with the user using a while loop. **Note** If you have any questions or need help with any of the exercises, feel free to leave a comment below. In the next topic, we will cover the basics of MATLAB scripts and functions, including definitions and differences.