Get amplitude decrease as a function of time in damped harmonic oscillations

I have all values of position as a function of time, attached graph. I'm trying to fit an exponential function to the upper peaks. Any tips?

Answer 1

[KSSV]

https://www.mathworks.com/examples/curvefitting/mw/curvefit-ex72685292-fit-exponential-models-using-the-fit-function

http://in.mathworks.com/help/curvefit/fit.html

https://in.mathworks.com/matlabcentral/answers/91159-how-do-i-fit-an-exponential-curve-to-my-data