BUG: rolling with axis=1

[seanlaw]

• fixes pd.expanding is incorrectly calculating window size when axis=1 #13753
• tests added / passed
• passes git diff upstream/master | flake8 --diff
• whatsnew entry

[jreback]

tests!

[seanlaw]

On it! Clearly new to TDD but will take a stab.

[jreback]

contributing guide

[codecov-io]

Current coverage is 84.56% (diff: 100%)

Merging #13757 into master will increase coverage by <.01%

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  Files           141        141          
  Lines         51195      51196     +1   
  Methods           0          0          
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+ Hits          43295      43296     +1   
  Misses         7900       7900          
  Partials          0          0          

Powered by Codecov. Last update 9f94e6a...5bad8f2

[jreback]

this need to address #13503 which is the main issue.

[seanlaw]

Are you saying that if I resolve the issue in #13503 then it will also automatically address the issue in #13753? It looks like #13503 is related to how .count() is implemented for .rolling. However, in my .expanding example, I am using .sum(). It would be helpful if you could point me in the right direction or which class to make changes in. Perhaps, in Rolling?

[jreback]

yes it's the same issue and is addressed in the same place

put tests in place first

[jreback]

pls reopen if you'd like to update