[docs]
def disp2vel(self, alpha='auto',ndays_mf=1):
"""Compute time series derivative via L1 trend filter (BIC-optimal parameter).
Uses https://pypi.org/project/trendfilter/
Parameters
----------
alpha : str or float, optional
Filter parameter; 'auto' for BIC-optimal. Default is 'auto'.
ndays_mf : int, optional
Median filter window (days) before L1-trend. Default is 1.
Returns
-------
Gts
New Gts instance; units m/yr.
"""
fts = self.l1trend(alpha=alpha,ndays_mf=ndays_mf)
new_gts = fts.ivel()
return new_gts