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
520137402,MDU6SXNzdWU1MjAxMzc0MDI=,3499,Documentation Feature Request: Rolling and Coordinates,3274,open,0,,,2,2019-11-08T17:24:40Z,2022-04-29T17:39:44Z,,CONTRIBUTOR,,,,"The documentation about iteration with `rolling` contains the following:
We can also manually iterate through Rolling objects:
for label, arr_window in r:
# arr_window is a view of x
It would help to explain what sort of thing `label` is, and how we can use it. It seems to be an object of type `Coordinate`, but `Coordinate` does not appear in the API reference.
So I would suggest the two following improvements:
1. Add an example of using the `label` and `arr_window`, maybe plotting the `arr_window` with the `label` used to give title.
2. Tweak the document generator to include docstrings from `Coordinate` in the API reference section.
3. Crossreference (hyperlink) from this section of the doc text to the API reference.
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3499/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue
663287119,MDExOlB1bGxSZXF1ZXN0NDU0NzI4NTM0,4244,Clarify drop_vars return value.,3274,closed,0,,,4,2020-07-21T20:27:08Z,2020-08-14T21:09:00Z,2020-08-14T21:07:36Z,CONTRIBUTOR,,0,pydata/xarray/pulls/4244,"The previous documentation was not clear about whether the variable
dropping was ""inplace"" or created a fresh Dataset.
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/4244/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,pull
585323675,MDU6SXNzdWU1ODUzMjM2NzU=,3873,Explanation of full DataFrame to Dataset translation,3274,open,0,,,4,2020-03-20T20:57:38Z,2020-03-20T23:13:25Z,,CONTRIBUTOR,,,,"Using `to_xarray()` on a `DataFrame` doesn't get me to the `Dataset` I want, because typically I want some of the `DataFrame`'s columns to be coordinates, and some Data Variables.
This Stack Exchange question and answer give *part* of the solution: https://stackoverflow.com/questions/59672658/reassigning-xarray-data-variable-to-xarray-coordinate
This tells us how to turn some of the data variables in the translated data set into coordinates. But that's not the full solution, because we also need the coordinates to be applied to the data variables. Somehow we need to add the variables that are now coordinates as dimensions.
This is probably somewhere in the docs, but it isn't pulled together into a big picture answer. It would be great if there was an end-to-end example of taking a pandas `DataFrame`, partitioning variables into coordinates and data variables, and being able to use the resulting coordinates (with `Dataset.sel()`) to address the data variables.
If that is in the online docs, I don't know how to find it. Thanks!
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3873/reactions"", ""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue
547702622,MDExOlB1bGxSZXF1ZXN0MzYxMTQzMTE1,3679,How do I add a new variable to dataset.,3274,closed,0,,,4,2020-01-09T20:26:14Z,2020-01-10T20:12:00Z,2020-01-10T20:02:23Z,CONTRIBUTOR,,0,pydata/xarray/pulls/3679,"Closes #3678
I don't have the full build environment: someone who does will have to make sure that I got the sphinx formatting right.
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3679/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,pull
547680465,MDU6SXNzdWU1NDc2ODA0NjU=,3678,Feature request: How Do I add a new variable to a data set?,3274,closed,0,,,5,2020-01-09T19:41:09Z,2020-01-10T20:02:23Z,2020-01-10T20:02:23Z,CONTRIBUTOR,,,,"A common thing to want to do is to create a new `DataArray` and add it to an existing `Dataset`, but the answer does not seem to appear in the ""How Do I?"" list.
Thanks!","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3678/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue
511477827,MDU6SXNzdWU1MTE0Nzc4Mjc=,3437,Request error handling in dataarray construction,3274,open,0,,,4,2019-10-23T17:48:11Z,2020-01-08T21:14:27Z,,CONTRIBUTOR,,,,"When I have a bad dimension in an xarray I get this error:
```
ValueError: different number of dimensions on data and dims: 2 vs 3
```
#### Expected Output
what I would like to see is
```
ValueError: different number of dimensions on data and dims: 2 vs 3 for variable Foo
```
The improvement I am asking for is here: https://github.com/pydata/xarray/blob/c8dac5866d2c54ee6b262b5060a701e0be1e40cb/xarray/core/dataarray.py#L368-L371
What I claim would be an improvement would be something like this:
```
data = _check_data_shape(data, coords, dims)
data = as_compatible_data(data)
try:
coords, dims = _infer_coords_and_dims(data.shape, coords, dims)
except Exception as e:
if name:
raise Exception(""Error finding coordinates and dims for variable %s: %s""%(name, e)
else:
raise e
variable = Variable(dims, data, attrs, encoding, fastpath=True)
```
I'm not an expert on python exception handling, so this is probably wrong.
#### Problem Description
The programmer cannot tell what variable causes the shape and dimension issue.
#### Output of ``xr.show_versions()``
python: 3.6.8 (default, Sep 6 2019, 11:45:11)
[GCC 4.2.1 Compatible Apple LLVM 10.0.1 (clang-1001.0.46.4)]
python-bits: 64
OS: Darwin
OS-release: 18.7.0
machine: x86_64
processor: i386
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
libhdf5: 1.10.2
libnetcdf: 4.6.3
xarray: 0.13.0
pandas: 0.25.2
numpy: 1.17.3
scipy: 1.3.1
netCDF4: 1.5.2
pydap: None
h5netcdf: None
h5py: 2.10.0
Nio: None
zarr: None
cftime: 1.0.3.4
nc_time_axis: None
PseudoNetCDF: None
rasterio: None
cfgrib: None
iris: None
bottleneck: 1.2.1
dask: None
distributed: None
matplotlib: 3.1.1
cartopy: None
seaborn: 0.9.0
numbagg: None
setuptools: 41.2.0
pip: 19.3.1
conda: None
pytest: 5.2.0
IPython: 7.8.0
sphinx: None
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3437/reactions"", ""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue
546956885,MDU6SXNzdWU1NDY5NTY4ODU=,3672,"Feature request: pull StackExchange answer into ""How Do I?""",3274,open,0,,,1,2020-01-08T16:08:53Z,2020-01-08T18:14:34Z,,CONTRIBUTOR,,,,"There's a great answer to a reshaping question -- how do I subdivide a dimension -- in this StackExchange Q&A: https://stackoverflow.com/questions/43015638/xarray-reshape-data-split-dimension
It would be great to get this moved into the ""How do I?"" section of the documentation.","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3672/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue
514191264,MDU6SXNzdWU1MTQxOTEyNjQ=,3461,Poor error message on Dataset.sum(axis=...),3274,open,0,,,10,2019-10-29T20:09:51Z,2019-11-18T01:24:56Z,,CONTRIBUTOR,,,,"
[ll_means.nc.gz](https://github.com/pydata/xarray/files/3785623/ll_means.nc.gz)
#### MCVE Code Sample
I'm attaching the relevant `.nc` file.
```python
foo = xr.open_dataset('ll_means.nc')
print(foo)
foo.sum(axis=1) # or foo.sum(axis=0)
```
Instead of getting a sum (either across the data variables or across the dimension shared between the variables), I get the error in the title: `ValueError: cannot supply both 'axis' and 'dim' arguments` even though I did not supply a `dim` argument. Furthermore, I get this error even when passing `dim=None`.
It's possible that I am doing something wrong, and it is just the error message that is bad, and not the behavior. I don't know enough to tell.
#### Expected Output
TBQH, I didn't know whether this would sum across the (single) dimension of this dataset, or if it would sum across the data variables along that dimension. I was experimenting to try to figure this out.
What I am trying to do is sum across the data variables, ""perpendicular"" to a dimension, instead of along it.
#### Problem Description
I assumed that summing across one of the axes would sum across the data variables, but perhaps that was a bad assumption. At any rate, the current behavior is undesirable.
#### Output of ``xr.show_versions()``
INSTALLED VERSIONS
------------------
commit: None
python: 3.7.4 (default, Jul 9 2019, 18:13:23)
[Clang 10.0.1 (clang-1001.0.46.4)]
python-bits: 64
OS: Darwin
OS-release: 18.7.0
machine: x86_64
processor: i386
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
libhdf5: 1.10.2
libnetcdf: 4.6.3
xarray: 0.12.3
pandas: 0.25.1
numpy: 1.17.1
scipy: 1.3.1
netCDF4: 1.5.2
pydap: None
h5netcdf: None
h5py: 2.9.0
Nio: None
zarr: None
cftime: 1.0.3.4
nc_time_axis: None
PseudoNetCDF: None
rasterio: None
cfgrib: None
iris: None
bottleneck: None
dask: None
distributed: None
matplotlib: 3.1.1
cartopy: None
seaborn: 0.9.0
numbagg: None
setuptools: 41.2.0
pip: 19.3.1
conda: None
pytest: None
IPython: 7.8.0
sphinx: None
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3461/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue