That you for your help,

I mean that I want to make a function between input and output,

For example, makeing a force function for a cantilever beam which is dependent on y-displacement, 

Shuch as this function.

Mx"+cx'+kx=f (x)

Actually I want add a force function which is depending on resulat (y displacement)

Dear Arash,

I think you have to use scripting technique, i.e. first solving initial problem, then apply new forces extracted from initial solution. Look for scripting manual, you'll probably find everything you need there.

Hope it helps,

Thank you,

But it is not possible,

As I mentioned, input and out put are couple at same time,

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