Apply function to time series period by period recursively

[mariusmjp]

Hi Iris Team

Is it a way to apply function to time series period by period as example you present in the documentation here:
https://iris-solutions-team.github.io/iris-reference/DataManagement/%40Series/apply.html

because when I tried to use this. It doesn't return result expected .

x = Series(qq(2020,1), 1);
func = @(x, t) 0,8*x(t-1) + 5;
x = apply(func, x, qq(2020,2):qq(2021,4))

I'm also try to use databank.apply but it doesn't work .
Do you have any solution for this?

Thanks