# spacepy.toolbox.tOverlapHalf

`spacepy.toolbox.``tOverlapHalf`(ts1, ts2, presort=False)

  Find overlapping elements in two lists of datetime objects

  This is one-half of tOverlap, i.e. it finds only occurrences where ts2 exists within the bounds of ts1, or the second element returned by tOverlap.

  Parameters: | ts1 : list first set of datetime object ts2 : list datatime object presort : bool Set to use a faster algorithm which assumes ts1 and ts2 are both sorted in ascending order. This speeds up the overlap comparison by about 50x, so it is worth sorting the list if one sort can be done for many calls to tOverlap
  Returns: | out : list indices of ts2 within interval of ts1 note: Returns empty list if no overlap found

  See also

  `tOverlap`, `tCommon`