MATLAB Script and Function Creation 2 — Questions and Answers
Question 1: What is the correct way to define a function that returns multiple output values in MATLAB?
- function [a, b] = myFunc(x) (Correct answer)
- function (a, b) = myFunc(x)
- function myFunc(x) returns [a, b]
- def myFunc(x) -> [a, b]:
Correct answer: function [a, b] = myFunc(x)
Multiple return values are declared in square brackets on the left side of the assignment in the function signature.
Question 2: Which command clears all variables from the MATLAB workspace at the start of a script?
- clear all (Correct answer)
- delete vars
- reset workspace
- flush()
Correct answer: clear all
`clear all` removes all variables, globals, and functions from the workspace.
Question 3: In a MATLAB function file, where must the primary function definition appear?
- At the top of the file before any other code (Correct answer)
- Anywhere in the file
- After all helper functions
- In a separate header block
Correct answer: At the top of the file before any other code
MATLAB requires the primary function to be the first function defined in a function file.
Question 4: What happens when a MATLAB script is run and a variable with the same name already exists in the workspace?
- The existing variable is overwritten (Correct answer)
- An error is thrown
- The script skips that assignment
- A new scope is created
Correct answer: The existing variable is overwritten
Scripts share the caller's workspace, so running a script overwrites any existing variable of the same name.
Question 5: Which keyword is used to exit a function early in MATLAB before reaching the end?
- return (Correct answer)
- exit
- break
- stop
Correct answer: return
`return` immediately exits the current function and returns control to the calling code.
Question 6: What does `nargin` return inside a MATLAB function?
- The number of input arguments passed by the caller (Correct answer)
- The number of output arguments requested
- The total number of declared inputs
- The index of the last argument
Correct answer: The number of input arguments passed by the caller
`nargin` returns the actual count of input arguments provided when the function was called.
Question 7: A local function defined inside a function file is accessible:
- Only by the functions in the same file (Correct answer)
- By any script in the current folder
- Globally across all MATLAB sessions
- Only from the MATLAB command window
Correct answer: Only by the functions in the same file
Local (subfunctions) are scoped to the file they are defined in and cannot be called from outside.
MATLAB Script and Function Creation 2
What is the correct way to define a function that returns multiple output values in MATLAB?