Question

What are persistent variables?

(a) Variables which retain values between calls to the function

(b) Variables which help in calling a function

(c) Variables which deal with functions

(d) Variables global to the function

I had been asked this question in a national level competition.

The query is from Functions topic in division MATLAB Basics of MATLAB

Answer 1

The correct option is (a) Variables which retain values between calls to the function

For explanation I would say: Persistent variables help to retain the value which has been produced by a sub-function. They are local to the sub-function but MATLAB reserves permanent storage for them so they might seem like global variables. They are never shown in the workspace so they differ from global variables.