Switch-case statements in MATLAB - Step-by-Step Execution

Concept Flow - Switch-case statements

Evaluate expression

↓

Compare with case 1

Yes / No↓

Run case 1

Yes / No↓

Run case 2

↓

Run default if no match

↓

End

The switch expression is evaluated once, then compared to each case in order. When a match is found, that case runs. If no match, the default runs.

Execution Sample

MATLAB

x = 2;
switch x
    case 1
        disp('One');
    case 2
        disp('Two');
    otherwise
        disp('Other');
end

This code checks the value of x and prints a message depending on which case matches.

Execution Table

Step	Expression Value	Case Compared	Match?	Action	Output
1	2	1	No	Check next case
2	2	2	Yes	Execute case 2 block	Two
3	2	otherwise	Skipped	Switch ends

💡 Match found at case 2, so switch ends after executing case 2 block.

Variable Tracker

Variable	Start	After Step 1	After Step 2	Final
x	2	2	2	2

Key Moments - 2 Insights

Why does the switch stop after executing case 2 and not check other cases?

In MATLAB switch-case, once a matching case is found and executed, the switch ends immediately as shown in execution_table step 2.

What happens if none of the cases match the expression value?

The 'otherwise' block runs if no case matches, as shown in the concept_flow and would appear in the execution_table if no matches occurred.

Visual Quiz - 3 Questions

Look at the execution table, what is the output at step 2?

A Two

B One

C Other

D No output

💡 Hint

Check the 'Output' column in execution_table row for step 2.

At which step does the switch statement stop checking cases?

A Step 1

B Step 2

C Step 3

D It checks all cases

💡 Hint

Look at the 'Match?' and 'Action' columns in execution_table to see when it stops.

If x was 5, which row in the execution table would show the executed case?

A Step 1

B Step 2

C Step 3

D No row, switch ends immediately

💡 Hint

Refer to the 'otherwise' case in concept_flow and execution_table for no matches.

Concept Snapshot

switch expression
    case value1
        % code for value1
    case value2
        % code for value2
    otherwise
        % code if no case matches
end

- Expression evaluated once
- Runs first matching case
- 'otherwise' runs if no match
- Switch ends after one case runs

Full Transcript

This visual execution shows how MATLAB switch-case statements work. The expression is evaluated once. Each case is checked in order. If a case matches, its code runs and the switch ends immediately. If no case matches, the 'otherwise' block runs. The example uses x=2, so case 2 matches and prints 'Two'. Variables remain unchanged during the switch. Key points include that only one case runs and the switch stops after that. The quiz questions help check understanding of output, stopping point, and default case behavior.