Hello,

I would go like this: Decide which gaussian and sigmoidal functions should work best for. Then use the fit function builder and create a duplicate of one function (e.g. the gaussian). Then add the new parameters neccessary to describe the sigmoidal function and create a new one that is basically y=gaussian_function + sigmoidal_function [e.g. y= y0+exp(-(x-x0)^2/w)+a/(1+exp(-k*(x-x0)))].

Parameter initialisation might prove a little difficult but if you have similar data, setting the initial values to fixed numeric ones for a start should be ok.

If you need more help, feel free to ask.

Best regards,

Moritz

first of all feed your data in two column in origin.

then draw a scatter or line plot whatever you desire.

then make graph tab active and go to analysis and choose fitting and nonlinear fitting in that window choose gaussian or other model which is for your data.

give me you mail id i will send a tutorial on it.

Dear Moritz,

Thanks for the reply.  I have attached the word file to show the steps that I have tried.  Finally I am getting the following error.

y = -- (Unknown function: K(X-D))

Please let me know if you know the reason.

Best regards,