Description
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I have checked that this issue has not already been reported.
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I have confirmed this bug exists on the latest version of pandas.
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I have confirmed this bug exists on the master branch of pandas.
Reproducible Example
import pandas as pd
import numpy as np
mi = pd.MultiIndex.from_tuples([(('a1','a2'),('b1','b2')), (('a1','a2'),('c1','c2'))])
df = pd.DataFrame(data=np.arange(2).reshape(1,2), columns=mi)
# This line works
df[(('a1','a2'),('b1','b2'))]
# This line would throw exception
df[[(('a1','a2'),('b1','b2'))]]Issue Description
When a data frame has columns of MultiIndex, and each level is a tuple. Selecting columns with array of column labels would raise ValueError.
ValueError: Buffer has wrong number of dimensions
But selecting with a single label works.
Expected Behavior
Return columns with no error.
Installed Versions
INSTALLED VERSIONS
commit : 5f648bf
python : 3.8.11.final.0
python-bits : 64
OS : Linux
OS-release : 5.4.0-1051-azure
Version : #53~18.04.1-Ubuntu SMP Fri Jun 18 22:32:58 UTC 2021
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : C.UTF-8
LOCALE : en_US.UTF-8
pandas : 1.3.2
numpy : 1.21.2
pytz : 2021.1
dateutil : 2.8.2
pip : 21.0.1
setuptools : 52.0.0.post20210125
Cython : 0.29.24
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : 4.6.3
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.0.1
IPython : 7.26.0
pandas_datareader: None
bs4 : 4.9.3
bottleneck : None
fsspec : None
fastparquet : None
gcsfs : None
matplotlib : 3.1.3
numexpr : 2.7.3
odfpy : None
openpyxl : 3.0.7
pandas_gbq : None
pyarrow : None
pyxlsb : None
s3fs : None
scipy : 1.7.1
sqlalchemy : 1.4.23
tables : 3.6.1
tabulate : 0.8.9
xarray : None
xlrd : 2.0.1
xlwt : None
numba : None