In building a sop via houdini 16 HDK,I have noticed that if you import parameters from a file,then changing these parameters won't cause the node to cook(cookMySop func).However,if you write these same parameters in your code,then changing them will cause the node to cook.

So what I want is :while my parameters are hard-coded,changing them won't cause the node to cook.
I want the node to cook only when I tell it to cook(by clicking a button).

It seems a problem of “data dependency graph”;but I have no idea what it is..