Crash sample
In[2]: df = pd.DataFrame(columns=['maybe_empty_column'])
...: pd.to_numeric(df['maybe_empty_column'], errors='ignore')
Process finished with exit code -1073741819 (0xC0000005)
Problem description
When calling to_numeric on an empty DataFrame column, python crashes with an access violation exit code (0xC0000005).
Expected Output
Should return an empty series with default dtype for empty series (int64)
for some reason, some empty Series objects work and some don't:
empty_that_works = pd.Series(['blabla',])[1:]
pd.to_numeric(empty_that_works)
empty_that_doesnt_work = pd.Series(dtype=object)
pd.to_numeric(empty_that_doesnt_work)
Output of pd.show_versions()
# Paste the output here pd.show_versions() here
INSTALLED VERSIONS
------------------
commit: None
python: 2.7.12.final.0
python-bits: 64
OS: Windows
OS-release: 8.1
machine: AMD64
processor: Intel64 Family 6 Model 60 Stepping 3, GenuineIntel
byteorder: little
LC_ALL: None
LANG: None
LOCALE: None.None
pandas: 0.20.1
pytest: 3.0.7
pip: 9.0.1
setuptools: 34.3.1
Cython: None
numpy: 1.12.1
scipy: 0.18.1
xarray: None
IPython: 5.3.0
sphinx: None
patsy: 0.4.1
dateutil: 2.6.0
pytz: 2016.10
blosc: None
bottleneck: None
tables: None
numexpr: 2.6.2
feather: None
matplotlib: 1.5.3
openpyxl: None
xlrd: 1.0.0
xlwt: None
xlsxwriter: None
lxml: None
bs4: 4.5.1
html5lib: 0.9999999
sqlalchemy: None
pymysql: None
psycopg2: None
jinja2: 2.9.6
s3fs: None
pandas_gbq: None
pandas_datareader: None
Comment From: TomAugspurger
Fixed in https://github.com/pandas-dev/pandas/pull/16305 I believe (0.20.2 was released today, so you can try upgrading). Let me know if that doesn't fix it for you.