`flagOffset` suggestions

I have the following comments to flagOffset:

  • Introduce the default value tolerance=np.inf
  • As far as I understood depends thresh_relative on the sign of the given parameter (i.e. I need thresh_relative=.5 and thresh_relative=-.5, if I want to flag on 'both sides' of a given curve), while thresh does not. If I am not mistaken here, I suggest to change that.

What do you think @luenensc ?

Edited by Bert Palm