clear persistent variable in subfunctions

Question

Torsten Reh 2021-12-1

回答： Monika Jaskolka 2021-12-1

Hi,

i have a script which repeadetly calls a subfunction. In that subfunction i have a persistent variable that grows by 1 everytime its called.

after im done i want to reset the persistent variable inside the subfunction.

fun1
fun1
fun1
clear fun1
fun1
function fun1
    persistent a
    if isempty(a); a = 0; end
    a = a+1
end

the output should be: 1-2-3-1

but it is 1-2-3-4, and when i run the script again it is 5-6-7-8.

I do NOT want to use:

clear all
clear functions

I just want to clear the persistent varibale inside that specific funtion.

I reckon i could pass a flag into fun1 to initialize it, but i believe there must be a better way to do this.

Answer 1

Monika Jaskolka 2021-12-1

"MATLAB clears persistent variables when you clear or modify a function that is in memory. "

So it doesn't seem like there is a way to do what you are asking for.