issue_comments

Table actions

4 rows where issue = 183713222 sorted by updated_at descending

✎ View and edit SQL

This data as json, CSV (advanced)

Suggested facets: reactions, created_at (date), updated_at (date)

author_association 3

issue 1

  • xarray.Dataset.var - xarray.DataArray.var - does it have ddof=1 parameter? · 4 ✖
id html_url issue_url node_id user created_at updated_at ▲ author_association body reactions performed_via_github_app issue
670978328 https://github.com/pydata/xarray/issues/1050#issuecomment-670978328 https://api.github.com/repos/pydata/xarray/issues/1050 MDEyOklzc3VlQ29tbWVudDY3MDk3ODMyOA== max-sixty 5635139 2020-08-08T21:59:18Z 2020-08-08T21:59:18Z MEMBER

Thanks for finding that @sjvrijn

I don't have a view on what we should use, so I would vote to defer to numpy (and pandas, which also seems to use 1), referencing that documentation to the extent xarray isn't changing anything.

But others probably have a stronger view on which ddof we should use?

 
{
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
   xarray.Dataset.var - xarray.DataArray.var - does it have ddof=1 parameter? 183713222
670971584 https://github.com/pydata/xarray/issues/1050#issuecomment-670971584 https://api.github.com/repos/pydata/xarray/issues/1050 MDEyOklzc3VlQ29tbWVudDY3MDk3MTU4NA== sjvrijn 8833517 2020-08-08T20:39:11Z 2020-08-08T20:39:11Z CONTRIBUTOR

In core/nanops.py there are some explicit defaults of ddof=0 within xarray, but I'm not sure if those are always used or if there are also cases where var (or std) are directly passed on to numpy/bottleneck/dask.

I'm considering two different options to clarify this:

  1. Add a docstring section on the ddof parameter specifying it uses ddof=0 as default for the reduction methods that use it, i.e. var and std. Possibly just copied from numpy's var page.
  2. Refer to numpy's documentation page in the docstring of all reduction methods for further reference.

Both would require some logic in core/ops.py: either to check for which reduce methods need a ddof paragraph, or to create the proper url (which has to adjust min and max to np.amin and np.amax respectively)

Is there any clear preference from anyone about this?

 
{
    "total_count": 1,
    "+1": 1,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
   xarray.Dataset.var - xarray.DataArray.var - does it have ddof=1 parameter? 183713222
457795347 https://github.com/pydata/xarray/issues/1050#issuecomment-457795347 https://api.github.com/repos/pydata/xarray/issues/1050 MDEyOklzc3VlQ29tbWVudDQ1Nzc5NTM0Nw== stale[bot] 26384082 2019-01-26T02:57:36Z 2019-01-26T02:57:36Z NONE

In order to maintain a list of currently relevant issues, we mark issues as stale after a period of inactivity If this issue remains relevant, please comment here; otherwise it will be marked as closed automatically

 
{
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
   xarray.Dataset.var - xarray.DataArray.var - does it have ddof=1 parameter? 183713222
254635928 https://github.com/pydata/xarray/issues/1050#issuecomment-254635928 https://api.github.com/repos/pydata/xarray/issues/1050 MDEyOklzc3VlQ29tbWVudDI1NDYzNTkyOA== shoyer 1217238 2016-10-18T20:52:24Z 2016-10-18T20:52:24Z MEMBER

Good question. Setting ddof should work. It's passed on to nanvar from NumPy or bottleneck, both of which default to ddof=0.

 
{
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
   xarray.Dataset.var - xarray.DataArray.var - does it have ddof=1 parameter? 183713222

Advanced export

JSON shape: default, array, newline-delimited, object

CSV options: 

CREATE TABLE [issue_comments] (
   [html_url] TEXT,
   [issue_url] TEXT,
   [id] INTEGER PRIMARY KEY,
   [node_id] TEXT,
   [user] INTEGER REFERENCES [users]([id]),
   [created_at] TEXT,
   [updated_at] TEXT,
   [author_association] TEXT,
   [body] TEXT,
   [reactions] TEXT,
   [performed_via_github_app] TEXT,
   [issue] INTEGER REFERENCES [issues]([id])
);
CREATE INDEX [idx_issue_comments_issue]
    ON [issue_comments] ([issue]);
CREATE INDEX [idx_issue_comments_user]
    ON [issue_comments] ([user]);