BUG: DatetimeIndex has become unhashable in 1.3.1? · Issue #42844 · pandas-dev/pandas (original) (raw)

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Hi,
Following code below was working with pandas 1.2.5.
It raises now an error with pandas 1.3.1.

Code Sample, a copy-pastable example

import pandas as pd import random

Right data

ts_open = pd.DatetimeIndex([ pd.Timestamp('2021/01/01 00:37'), pd.Timestamp('2021/01/01 00:40'), pd.Timestamp('2021/01/01 01:00'), pd.Timestamp('2021/01/01 03:45'), pd.Timestamp('2021/01/01 03:59'), pd.Timestamp('2021/01/01 05:20')]) length = len(ts_open) random.seed(1) volume = random.sample(range(1, length+1), length) df_smpl = pd.DataFrame({'volume' : volume, 'ts_open': ts_open})

Left data

ts_full = pd.date_range(start=pd.Timestamp('2021/01/01 00:00'), periods=7, freq='1h') ts_event = ts_full[:-1] length_ipr = len(ts_event) random.seed(2) volume = random.sample(range(20, length_ipr+20), length_ipr) df_ipr = pd.DataFrame({'volume' : volume, 'timestamp': ts_event})

at = ts_full[1:] df_smpl.index = df_smpl['ts_open']

Test

df_full = pd.merge_asof(df_ipr, df_smpl, left_on=at, right_index=True, allow_exact_matches=False, direction='backward')

Error message:

Traceback (most recent call last):

File "", line 30, in df_full = pd.merge_asof(df_ipr, df_smpl,

File "/home/yoh/anaconda3/lib/python3.8/site-packages/pandas/core/reshape/merge.py", line 581, in merge_asof op = _AsOfMerge(

File "/home/yoh/anaconda3/lib/python3.8/site-packages/pandas/core/reshape/merge.py", line 1736, in init _OrderedMerge.init(

File "/home/yoh/anaconda3/lib/python3.8/site-packages/pandas/core/reshape/merge.py", line 1619, in init _MergeOperation.init(

File "/home/yoh/anaconda3/lib/python3.8/site-packages/pandas/core/reshape/merge.py", line 682, in init self._validate_specification()

File "/home/yoh/anaconda3/lib/python3.8/site-packages/pandas/core/reshape/merge.py", line 1782, in _validate_specification if left_on in self.left.columns

File "/home/yoh/anaconda3/lib/python3.8/site-packages/pandas/core/indexes/base.py", line 4572, in contains hash(key)

TypeError: unhashable type: 'DatetimeIndex'

Output of pd.show_versions()

INSTALLED VERSIONS

commit : c7f7443
python : 3.8.8.final.0
python-bits : 64
OS : Linux
OS-release : 5.8.0-63-generic
Version : #71~20.04.1-Ubuntu SMP Thu Jul 15 17:46:08 UTC 2021
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.3.1
numpy : 1.20.3
pytz : 2021.1
dateutil : 2.8.2
pip : 21.1.3
setuptools : 52.0.0.post20210125
Cython : 0.29.24
pytest : 6.2.4
hypothesis : None
sphinx : 4.0.2
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 2.11.3
IPython : 7.22.0
pandas_datareader: None
bs4 : 4.9.3
bottleneck : None
fsspec : 2021.07.0
fastparquet : 0.7.0
gcsfs : None
matplotlib : 3.3.4
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : 3.0.0
pyxlsb : None
s3fs : None
scipy : 1.6.2
sqlalchemy : None
tables : None
tabulate : 0.8.9
xarray : 0.19.0
xlrd : None
xlwt : None
numba : 0.53.1