Gradual change in parameter for perfect foresight model

Good afternoon! I am solving a deterministic model. I want to change the parameter value from 0 to 0.015. Currently, I do it like this:

var eps_xii;
periods 0:2000 2000:5000;
values 0 0.015;

However, I want the change to be gradual (reach 0.015 smoothly over time) — so the simulated path shows the transition. How do I do it?

You can for example use

var eps_xii;
periods 1:100;
values (temp);

It worked, thank you so much!