Series.str.rsplit not working with regex patterns (v 0.24.2 and 0.25.2) #29633
Description
Code Sample, a copy-pastable example if possible
import pandas as pd
S = pd.Series(['1+1=2'])
S.str.rsplit(r'\+|=')
# returns:
0 [1+1=2]
S.str.rsplit(r'\+|=', expand=True)
# returns:
0
0 1+1=2Problem description
The str.rsplit method is not recognizing regex patterns. This example above is from the documentation.
Expected Output
S.str.rsplit(r'\+|=')
0 [1, 2, 3]
S.str.rsplit(r'\+|=', expand=True)
0 1 2
0 1 1 2Output of pd.show_versions()
Version 0.24.2:
pandas: 0.24.2
pytest: 5.0.1
pip: 19.1.1
setuptools: 41.0.1
Cython: 0.29.12
numpy: 1.16.4
scipy: 1.2.1
pyarrow: None
xarray: None
IPython: 7.6.1
sphinx: 2.1.2
patsy: 0.5.1
dateutil: 2.8.0
pytz: 2019.1
blosc: None
bottleneck: 1.2.1
tables: 3.5.2
numexpr: 2.6.9
feather: None
matplotlib: 3.1.0
openpyxl: 2.6.2
xlrd: 1.2.0
xlwt: 1.3.0
xlsxwriter: 1.1.8
lxml.etree: 4.3.4
bs4: 4.7.1
html5lib: 1.0.1
sqlalchemy: 1.3.5
pymysql: None
psycopg2: None
jinja2: 2.10.1
s3fs: None
fastparquet: None
pandas_gbq: None
pandas_datareader: None
gcsfs: None
Version 0.25.2:
pandas : 0.25.2
numpy : 1.17.3
pytz : 2019.3
dateutil : 2.8.1
pip : 19.2.3
setuptools : 41.2.0
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : 4.4.1
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : None
IPython : 7.8.0
pandas_datareader: None
bs4 : 4.8.1
bottleneck : None
fastparquet : None
gcsfs : None
lxml.etree : 4.4.1
matplotlib : None
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pytables : None
s3fs : None
scipy : None
sqlalchemy : None
tables : None
xarray : None
xlrd : None
xlwt : None
xlsxwriter : None