Closed
Description
Minimal example:
>>> import pandas as pd
>>> s = pd.Series(index=range(2010, 2020))
>>> s.loc[2015:2010:-1] = [6, 5, 4, 3, 2, 1]
Traceback (most recent call last):
[...]
ValueError: cannot set using a slice indexer with a different length than the value
I see no reason why this shouldn't work, as setting with the forward slicer works without problems, and getting with the reverse slicer also works without issue:
>>> # turn list around because slicer is (not) reversed compared to above
>>> s.loc[2010:2015] = [6, 5, 4, 3, 2, 1][::-1]
>>> s
2010 1.0
2011 2.0
2012 3.0
2013 4.0
2014 5.0
2015 6.0
2016 NaN
2017 NaN
2018 NaN
2019 NaN
dtype: float64
>>> s.loc[2015:2010:-1] == [6, 5, 4, 3, 2, 1] # comparison, not assignment
2015 True
2014 True
2013 True
2012 True
2011 True
2010 True
dtype: bool
PS: For the failure, it does not matter if the RHS is a np.array, etc.