Description
Code Sample, a copy-pastable example if possible
from datetime import datetime, timedelta
import pandas as pd
times = [datetime.now() + timedelta(hours=i) for i in range(10)] * 2
ids = ['foo', 'bar'] * 10
df = pd.DataFrame({'time': times, 'id': ids, 'value': range(20)})Problem description
This line:
df.set_index('time').groupby('id').resample('H').agg(['mean', 'std'])
causes this error:
Exception: Column(s) id already selected
however invoking mean and std individually work as expected:
df.set_index('time').groupby('id').resample('H').mean()
df.set_index('time').groupby('id').resample('H').std()
Expected Output
A dataframe with the combined outputs of:
>>> df.set_index('time').groupby('id').resample('H').mean()
value
id time
bar 2018-11-06 12:00:00 6.0
2018-11-06 13:00:00 NaN
2018-11-06 14:00:00 8.0
2018-11-06 15:00:00 NaN
2018-11-06 16:00:00 10.0
2018-11-06 17:00:00 NaN
2018-11-06 18:00:00 12.0
2018-11-06 19:00:00 NaN
2018-11-06 20:00:00 14.0
foo 2018-11-06 11:00:00 5.0
2018-11-06 12:00:00 NaN
2018-11-06 13:00:00 7.0
2018-11-06 14:00:00 NaN
2018-11-06 15:00:00 9.0
2018-11-06 16:00:00 NaN
2018-11-06 17:00:00 11.0
2018-11-06 18:00:00 NaN
2018-11-06 19:00:00 13.0
>>> df.set_index('time').groupby('id').resample('H').std()
value
id time
bar 2018-11-06 12:00:00 7.071068
2018-11-06 13:00:00 NaN
2018-11-06 14:00:00 7.071068
2018-11-06 15:00:00 NaN
2018-11-06 16:00:00 7.071068
2018-11-06 17:00:00 NaN
2018-11-06 18:00:00 7.071068
2018-11-06 19:00:00 NaN
2018-11-06 20:00:00 7.071068
foo 2018-11-06 11:00:00 7.071068
2018-11-06 12:00:00 NaN
2018-11-06 13:00:00 7.071068
2018-11-06 14:00:00 NaN
2018-11-06 15:00:00 7.071068
2018-11-06 16:00:00 NaN
2018-11-06 17:00:00 7.071068
2018-11-06 18:00:00 NaN
2018-11-06 19:00:00 7.071068
Output of pd.show_versions()
pd.show_versions()
INSTALLED VERSIONS
commit: None
python: 3.6.6.final.0
python-bits: 64
OS: Darwin
OS-release: 16.7.0
machine: x86_64
processor: i386
byteorder: little
LC_ALL: en_US.UTF-8
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
pandas: 0.23.3
pytest: 3.7.1
pip: 18.0
setuptools: 39.1.0
Cython: None
numpy: 1.14.5
scipy: 1.1.0
pyarrow: None
xarray: None
IPython: 6.4.0
sphinx: 1.7.5
patsy: None
dateutil: 2.7.3
pytz: 2018.5
blosc: None
bottleneck: None
tables: None
numexpr: None
feather: None
matplotlib: 2.2.2
openpyxl: None
xlrd: None
xlwt: None
xlsxwriter: None
lxml: None
bs4: None
html5lib: 1.0.1
sqlalchemy: 1.2.12
pymysql: None
psycopg2: None
jinja2: 2.10
s3fs: None
fastparquet: None
pandas_gbq: None
pandas_datareader: None