# How to detect & eliminate the initial lag that occurs in time series data

I am working with vehicle data. In order to better study the system and I am looking for a automated tool that can delete the initial lag where no work function takes place. It'll be great if someone can guide me to a library/package to do the same. I have included a schematic of what I am seeking below -

• perhaps apply the second derivative (the derivative of the derivative) where the first derivative is simply $x[n]-x[n-1]$ and look for the maximum magnitude. – robert bristow-johnson Feb 20 at 2:07