def _aggregate(self, arg, *args, **kwargs):
"""
provide an implementation for the aggregators
Parameters
----------
arg : string, dict, function
*args : args to pass on to the function
**kwargs : kwargs to pass on to the function
Returns
-------
tuple of result, how
Notes
-----
how can be a string describe the required post-processing, or
None if not required
"""
is_aggregator = lambda x: isinstance(x, (list, tuple, dict))
is_nested_renamer = False
_level = kwargs.pop('_level', None)
if isinstance(arg, compat.string_types):
return getattr(self, arg)(*args, **kwargs), None
if isinstance(arg, dict):
# aggregate based on the passed dict
if self.axis != 0: # pragma: no cover
raise ValueError('Can only pass dict with axis=0')
obj = self._selected_obj
# if we have a dict of any non-scalars
# eg. {'A' : ['mean']}, normalize all to
# be list-likes
if any(is_aggregator(x) for x in compat.itervalues(arg)):
new_arg = compat.OrderedDict()
for k, v in compat.iteritems(arg):
if not isinstance(v, (tuple, list, dict)):
new_arg[k] = [v]
else:
new_arg[k] = v
# the keys must be in the columns
# for ndim=2, or renamers for ndim=1
# ok
# {'A': { 'ra': 'mean' }}
# {'A': { 'ra': ['mean'] }}
# {'ra': ['mean']}
# not ok
# {'ra' : { 'A' : 'mean' }}
if isinstance(v, dict):
is_nested_renamer = True
if k not in obj.columns:
raise SpecificationError('cannot perform renaming '
'for {0} with a nested '
'dictionary'.format(k))
arg = new_arg
from pandas.tools.concat import concat
def _agg_1dim(name, how, subset=None):
"""
aggregate a 1-dim with how
"""
colg = self._gotitem(name, ndim=1, subset=subset)
if colg.ndim != 1:
raise SpecificationError("nested dictionary is ambiguous "
"in aggregation")
return colg.aggregate(how, _level=(_level or 0) + 1)
def _agg_2dim(name, how):
"""
aggregate a 2-dim with how
"""
colg = self._gotitem(self._selection, ndim=2, subset=obj)
return colg.aggregate(how, _level=None)
def _agg(arg, func):
"""
run the aggregations over the arg with func
return an OrderedDict
"""
result = compat.OrderedDict()
for fname, agg_how in compat.iteritems(arg):
result[fname] = func(fname, agg_how)
return result
# set the final keys
keys = list(compat.iterkeys(arg))
result = compat.OrderedDict()
# nested renamer
if is_nested_renamer:
result = list(_agg(arg, _agg_1dim).values())
if all(isinstance(r, dict) for r in result):
result, results = compat.OrderedDict(), result
for r in results:
result.update(r)
keys = list(compat.iterkeys(result))
else:
if self._selection is not None:
keys = None
# some selection on the object
elif self._selection is not None:
sl = set(self._selection_list)
# we are a Series like object,
# but may have multiple aggregations
if len(sl) == 1:
result = _agg(
arg, lambda fname, agg_how: _agg_1dim(
self._selection, agg_how))
# we are selecting the same set as we are aggregating
elif not len(sl - set(compat.iterkeys(arg))):
result = _agg(arg, _agg_1dim)
# we are a DataFrame, with possibly multiple aggregations
else:
result = _agg(arg, _agg_2dim)
# no selection
else:
try:
result = _agg(arg, _agg_1dim)
except SpecificationError:
# we are aggregating expecting all 1d-returns
# but we have 2d
result = _agg(arg, _agg_2dim)
# combine results
if isinstance(result, list):
result = concat(result, keys=keys, axis=1)
elif isinstance(list(compat.itervalues(result))[0], ABCDataFrame):
result = concat([result[k] for k in keys], keys=keys, axis=1)
else:
from pandas import DataFrame
result = DataFrame(result)
return result, True
elif hasattr(arg, '__iter__'):
return self._aggregate_multiple_funcs(arg, _level=_level), None
else:
result = None
cy_func = self._is_cython_func(arg)
if cy_func and not args and not kwargs:
return getattr(self, cy_func)(), None
# caller can react
return result, True
def _aggregate(self, arg, *args, **kwargs):
"""
provide an implementation for the aggregators
Parameters
----------
arg : string, dict, function
*args : args to pass on to the function
**kwargs : kwargs to pass on to the function
Returns
-------
tuple of result, how
Notes
-----
how can be a string describe the required post-processing, or
None if not required
"""
is_aggregator = lambda x: isinstance(x, (list, tuple, dict))
is_nested_renamer = False
_axis = kwargs.pop('_axis', None)
if _axis is None:
_axis = getattr(self, 'axis', 0)
_level = kwargs.pop('_level', None)
if isinstance(arg, compat.string_types):
return self._try_aggregate_string_function(arg, *args,
**kwargs), None
if isinstance(arg, dict):
# aggregate based on the passed dict
if _axis != 0: # pragma: no cover
raise ValueError('Can only pass dict with axis=0')
obj = self._selected_obj
def nested_renaming_depr(level=4):
# deprecation of nested renaming
# GH 15931
warnings.warn(("using a dict with renaming "
"is deprecated and will be removed in a future "
"version"),
FutureWarning,
stacklevel=level)
# if we have a dict of any non-scalars
# eg. {'A' : ['mean']}, normalize all to
# be list-likes
if any(is_aggregator(x) for x in compat.itervalues(arg)):
new_arg = compat.OrderedDict()
for k, v in compat.iteritems(arg):
if not isinstance(v, (tuple, list, dict)):
new_arg[k] = [v]
else:
new_arg[k] = v
# the keys must be in the columns
# for ndim=2, or renamers for ndim=1
# ok for now, but deprecated
# {'A': { 'ra': 'mean' }}
# {'A': { 'ra': ['mean'] }}
# {'ra': ['mean']}
# not ok
# {'ra' : { 'A' : 'mean' }}
if isinstance(v, dict):
is_nested_renamer = True
if k not in obj.columns:
msg = ('cannot perform renaming for {key} with a '
'nested dictionary').format(key=k)
raise SpecificationError(msg)
nested_renaming_depr(4 + (_level or 0))
elif isinstance(obj, ABCSeries):
nested_renaming_depr()
elif isinstance(obj, ABCDataFrame) and \
k not in obj.columns:
raise KeyError(
"Column '{col}' does not exist!".format(col=k))
arg = new_arg
else:
# deprecation of renaming keys
# GH 15931
keys = list(compat.iterkeys(arg))
if (isinstance(obj, ABCDataFrame)
and len(obj.columns.intersection(keys)) != len(keys)):
nested_renaming_depr()
from pandas.core.reshape.concat import concat
def _agg_1dim(name, how, subset=None):
"""
aggregate a 1-dim with how
"""
colg = self._gotitem(name, ndim=1, subset=subset)
if colg.ndim != 1:
raise SpecificationError("nested dictionary is ambiguous "
"in aggregation")
return colg.aggregate(how, _level=(_level or 0) + 1)
def _agg_2dim(name, how):
"""
aggregate a 2-dim with how
"""
colg = self._gotitem(self._selection, ndim=2, subset=obj)
return colg.aggregate(how, _level=None)
def _agg(arg, func):
"""
run the aggregations over the arg with func
return an OrderedDict
"""
result = compat.OrderedDict()
for fname, agg_how in compat.iteritems(arg):
result[fname] = func(fname, agg_how)
return result
# set the final keys
keys = list(compat.iterkeys(arg))
result = compat.OrderedDict()
# nested renamer
if is_nested_renamer:
result = list(_agg(arg, _agg_1dim).values())
if all(isinstance(r, dict) for r in result):
result, results = compat.OrderedDict(), result
for r in results:
result.update(r)
keys = list(compat.iterkeys(result))
else:
if self._selection is not None:
keys = None
# some selection on the object
elif self._selection is not None:
sl = set(self._selection_list)
# we are a Series like object,
# but may have multiple aggregations
if len(sl) == 1:
result = _agg(
arg, lambda fname, agg_how: _agg_1dim(
self._selection, agg_how))
# we are selecting the same set as we are aggregating
elif not len(sl - set(keys)):
result = _agg(arg, _agg_1dim)
# we are a DataFrame, with possibly multiple aggregations
else:
result = _agg(arg, _agg_2dim)
# no selection
else:
try:
result = _agg(arg, _agg_1dim)
except SpecificationError:
# we are aggregating expecting all 1d-returns
# but we have 2d
result = _agg(arg, _agg_2dim)
# combine results
def is_any_series():
# return a boolean if we have *any* nested series
return any(
isinstance(r, ABCSeries)
for r in compat.itervalues(result))
def is_any_frame():
# return a boolean if we have *any* nested series
return any(
isinstance(r, ABCDataFrame)
for r in compat.itervalues(result))
if isinstance(result, list):
return concat(result, keys=keys, axis=1, sort=True), True
elif is_any_frame():
# we have a dict of DataFrames
# return a MI DataFrame
return concat([result[k] for k in keys], keys=keys,
axis=1), True
elif isinstance(self, ABCSeries) and is_any_series():
# we have a dict of Series
# return a MI Series
try:
result = concat(result)
except TypeError:
# we want to give a nice error here if
# we have non-same sized objects, so
# we don't automatically broadcast
raise ValueError("cannot perform both aggregation "
"and transformation operations "
"simultaneously")
return result, True
# fall thru
from pandas import DataFrame, Series
try:
result = DataFrame(result)
except ValueError:
# we have a dict of scalars
result = Series(result, name=getattr(self, 'name', None))
return result, True
elif is_list_like(arg) and arg not in compat.string_types:
# we require a list, but not an 'str'
return self._aggregate_multiple_funcs(arg,
_level=_level,
_axis=_axis), None
else:
result = None
f = self._is_cython_func(arg)
if f and not args and not kwargs:
return getattr(self, f)(), None
# caller can react
return result, True
def _aggregate(self, arg, *args, **kwargs):
"""
provide an implementation for the aggregators
Parameters
----------
arg : string, dict, function
*args : args to pass on to the function
**kwargs : kwargs to pass on to the function
Returns
-------
tuple of result, how
Notes
-----
how can be a string describe the required post-processing, or
None if not required
"""
_level = kwargs.pop('_level', None)
if isinstance(arg, compat.string_types):
return getattr(self, arg)(*args, **kwargs), None
result = compat.OrderedDict()
if isinstance(arg, dict):
if self.axis != 0: # pragma: no cover
raise ValueError('Can only pass dict with axis=0')
obj = self._selected_obj
if any(isinstance(x, (list, tuple, dict)) for x in arg.values()):
new_arg = compat.OrderedDict()
for k, v in compat.iteritems(arg):
if not isinstance(v, (tuple, list, dict)):
new_arg[k] = [v]
else:
new_arg[k] = v
arg = new_arg
keys = []
if self._selection is not None:
subset = obj
for fname, agg_how in compat.iteritems(arg):
colg = self._gotitem(self._selection,
ndim=1,
subset=subset)
result[fname] = colg.aggregate(agg_how, _level=None)
keys.append(fname)
else:
for col, agg_how in compat.iteritems(arg):
colg = self._gotitem(col, ndim=1)
result[col] = colg.aggregate(agg_how, _level=None)
keys.append(col)
if isinstance(list(result.values())[0], com.ABCDataFrame):
from pandas.tools.merge import concat
result = concat([result[k] for k in keys], keys=keys, axis=1)
else:
from pandas import DataFrame
result = DataFrame(result)
return result, True
elif hasattr(arg, '__iter__'):
return self._aggregate_multiple_funcs(arg, _level=_level), None
else:
result = None
cy_func = self._is_cython_func(arg)
if cy_func and not args and not kwargs:
return getattr(self, cy_func)(), None
# caller can react
return result, True
