def deltatime_to_utctime(
dataarray: xr.DataArray,
start_epoch: np.datetime64 = np.datetime64("2018-01-01T00:00:00.000000"),
) -> xr.DataArray:
"""
Converts GPS time in nanoseconds from an epoch (default is 2018 Jan 1st)
to Coordinated Universal Time (UTC).
Note, does not account for leap seconds! There are none declared since the
last one announced on 31/12/2016, so it should be fine for now as of 2020.
"""
try:
start_epoch = dataarray.__class__(start_epoch).squeeze()
except ValueError: # Could not convert object to NumPy timedelta
pass
utc_time: xr.DataArray = start_epoch + dataarray
return utc_time
