Manage a variable like a function

it is possible to set a variable in blueprint using a fuzzy logic?
I want set this variable and manage it through a graphic like an animation


If by fuzzy logic you mean fuzzy logic, then you need to do it all by yourself, unreal does not support fuzzy logic.

You can store some values as curve (its bezier graph that you can edit). Then you can read its value at some point.
If you close it all inside function and make it pure you get node that works just like variable.
I think it is read only, you probably can change points and tangents of it, but i am not quite sure that.