How do i create a custom function for sensitivity analysis

Hi,

I am trying to do a sensitivity analaysis on a circuit voltage signal. What i want to do is to observe the sensitivity of the RMS signal whenever i try to change a parameter.

In order to do that i have to create a custom function.

the custom function that i wrote is:

function y=getRMS(u)
y=rms(u);
end

But it does not work.

Can anyone tell me how to write a custom function for sensitivity analysis

[per isakson]

"But it does not work." In what way does it fail to work?

[Image Analyst]

How is u computed from the parameter you're going to change? What is the changing parameter called? For example, it's called "theParameter" and "u" is some vector that is built using that value of "theParameter".

[Marc Saade]

I am varying a capacitor and want to observe the change in RMS value of the output voltage.

The sensitivity application does not have RMS so i need to create an RMS function

This is the function

function y =GetRMS(u)
    y=RMS(u);
end

I attached the circuit whitch contain a wire named VVo which is the output voltage and the Error shows the error i get when i run the customize function in sensitivity analysis.

Please look in to them.

Thank you