issues: 226549366

This data as json

id node_id number title user state locked assignee milestone comments created_at updated_at closed_at author_association active_lock_reason draft pull_request body reactions performed_via_github_app state_reason repo type
226549366 MDU6SXNzdWUyMjY1NDkzNjY= 1399 `decode_cf_datetime()` slow because `pd.to_timedelta()` is slow if floats are passed 102827 closed 0     6 2017-05-05T11:48:00Z 2017-07-25T17:42:52Z 2017-07-25T17:42:52Z CONTRIBUTOR      

Hi, decode_cf_datetime is slowed down because it always passes floats to pd.to_timedelta, while pd.to_timedelta is much faster when working on integers.

Here is a notebook that shows the differences. Working with integers is approx. one order of magnitude faster.

Hence, it would be great to automatically do the conversion from raw time value floats to integers in nanoseconds where possible (likely limited to resolutions bellow days or hours to avoid coping with different durations numbers of nanoseconds within e.g. different months).

As alternative, maybe avoid forcing the cast to floats and indicate in the docstring that the raw values should be integers to speed up the conversion.

This could possibly also be resolved in pd.to_timedelta but I assume it will be more complicated to deal with all the edge cases there.

 
{
    "url": "https://api.github.com/repos/pydata/xarray/issues/1399/reactions",
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
   completed 13221727 issue

Links from other tables