MATLAB Desktop and Command Window - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of Command Window Variable Display

What will be displayed in the MATLAB Command Window after running this code?

MATLAB

x = 5;
disp(x + 3);

A x + 3

B 5 + 3

C 8

D Error: Undefined function or variable 'x + 3'.

💡 Hint

The disp function shows the value of the expression inside it.

The variable x is assigned 5. disp(x + 3) calculates 5 + 3 and displays 8.

🧠 Conceptual

intermediate

Understanding Command Window Behavior

Which statement about the MATLAB Command Window is true?

A It only shows output when the semicolon is omitted at the end of a command.

B It automatically saves all commands to a file.

C It cannot display text messages using disp or fprintf.

D It requires restarting MATLAB to clear previous outputs.

💡 Hint

Think about how MATLAB shows or hides output after commands.

In MATLAB, ending a command with a semicolon suppresses output in the Command Window. Without it, MATLAB displays the result.

🔧 Debug

advanced

Identify the Error in Command Window Input

What error will MATLAB show when running this command in the Command Window?

MATLAB

y = 10
z = y + 5;

A Error: Undefined variable 'y'.

B Error: Unexpected end of statement.

C Error: Missing semicolon after first line.

D No error; y is assigned 10 and z is assigned 15.

💡 Hint

Check if omitting semicolon causes an error or just output.

In MATLAB, omitting a semicolon does not cause an error; it only shows output. Both assignments are valid.

❓ Predict Output

advanced

Command Window Output with fprintf

What is the output in the Command Window after running this code?

MATLAB

a = 7;
fprintf('Value of a is %d\n', a);

A Error: Invalid format specifier.

B Value of a is 7

C 7

D Value of a is %d

💡 Hint

fprintf prints formatted text to the Command Window.

The %d is replaced by the value of a (7), so the output is 'Value of a is 7'.

🧠 Conceptual

expert

Command Window Variable Persistence

After running a script that defines variable x = 10 in the Command Window, what happens to x if you clear the Command Window using the 'clc' command?

A Variable x remains in memory and can be used.

B Variable x is reset to zero.

C Variable x is deleted and no longer exists.

D Variable x is saved to a file automatically.

💡 Hint

Think about what 'clc' does versus 'clear'.

'clc' clears the Command Window text but does not remove variables from memory. 'clear' removes variables.