pandas (original) (raw)

GroupBy.rolling.agg failed with Column(s) low already selected

data = pd.DataFrame({"stock": [1, 1, 1, 2, 2, 2, 2], "low": [10, 20, 30, 10, 30, 40, 80]}) data.set_index("stock", inplace=True)

failed

data.groupby(level="stock").rolling(2).agg({"low": {"mean": "mean", "max": "max"}})

works

data.rolling(2).agg({"low": {"mean": "mean", "max": "max"}})

This also hits groupby().resample.agg

In [13]: df = pd.DataFrame({"A": pd.to_datetime(['2015', '2017']), "B": [1, 1]})

In [14]: df Out[14]: A B 0 2015-01-01 1 1 2017-01-01 1

In [15]: df.set_index("A").groupby([0, 0]).resample("AS") Out[15]: DatetimeIndexResamplerGroupby [freq=<YearBegin: month=1>, axis=0, closed=left, label=left, convention=e, base=0]

In [16]: df.set_index("A").groupby([0, 0]).resample("AS").agg(['sum', 'count'])

Exception Traceback (most recent call last) in () ----> 1 df.set_index("A").groupby([0, 0]).resample("AS").agg(['sum', 'count'])

~/Envs/pandas-dev/lib/python3.6/site-packages/pandas/pandas/core/resample.py in aggregate(self, arg, *args, **kwargs) 339 340 self._set_binner() --> 341 result, how = self._aggregate(arg, *args, **kwargs) 342 if result is None: 343 result = self._groupby_and_aggregate(arg,

~/Envs/pandas-dev/lib/python3.6/site-packages/pandas/pandas/core/base.py in _aggregate(self, arg, *args, **kwargs) 538 return self._aggregate_multiple_funcs(arg, 539 _level=_level, --> 540 _axis=_axis), None 541 else: 542 result = None

~/Envs/pandas-dev/lib/python3.6/site-packages/pandas/pandas/core/base.py in _aggregate_multiple_funcs(self, arg, _level, _axis) 583 try: 584 colg = self._gotitem(col, ndim=1, subset=obj[col]) --> 585 results.append(colg.aggregate(arg)) 586 keys.append(col) 587 except (TypeError, DataError):

~/Envs/pandas-dev/lib/python3.6/site-packages/pandas/pandas/core/base.py in _aggregate_multiple_funcs(self, arg, _level, _axis) 582 for col in obj: 583 try: --> 584 colg = self._gotitem(col, ndim=1, subset=obj[col]) 585 results.append(colg.aggregate(arg)) 586 keys.append(col)

~/Envs/pandas-dev/lib/python3.6/site-packages/pandas/pandas/core/base.py in _gotitem(self, key, ndim, subset) 675 for attr in self._attributes]) 676 self = self.class(subset, --> 677 groupby=self._groupby[key], 678 parent=self, 679 **kwargs)

~/Envs/pandas-dev/lib/python3.6/site-packages/pandas/pandas/core/base.py in getitem(self, key) 241 if self._selection is not None: 242 raise Exception('Column(s) {selection} already selected' --> 243 .format(selection=self._selection)) 244 245 if isinstance(key, (list, tuple, ABCSeries, ABCIndexClass,

Exception: Column(s) B already selected

Problem description

It's not work as expected

Output of `pd.show_versions()`

INSTALLED VERSIONS ------------------ commit: None python: 3.5.2.final.0 python-bits: 64 OS: Linux OS-release: 4.4.0-53-generic machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: en_US.UTF-8 LOCALE: en_US.UTF-8

pandas: 0.19.2+0.g825876c.dirty
nose: 1.3.7
pip: 9.0.1
setuptools: 27.2.0
Cython: 0.24.1
numpy: 1.11.1
scipy: 0.18.1
statsmodels: 0.6.1
xarray: None
IPython: 5.1.0
sphinx: 1.4.6
patsy: 0.4.1
dateutil: 2.5.3
pytz: 2016.6.1
blosc: None
bottleneck: 1.1.0
tables: 3.2.3.1
numexpr: 2.6.1
matplotlib: 1.5.3
openpyxl: 2.3.2
xlrd: 1.0.0
xlwt: 1.1.2
xlsxwriter: 0.9.3
lxml: 3.6.4
bs4: 4.5.1
html5lib: None
httplib2: None
apiclient: None
sqlalchemy: 1.0.13
pymysql: 0.7.9.None
psycopg2: None
jinja2: 2.8
boto: 2.42.0
pandas_datareader: None