def __getitem__(self, key):
from pandas.core.dtypes.common import is_list_like, is_integer, is_iterator
key = com.apply_if_callable(key, self)
# shortcut if the key is in columns
try:
if self.columns.is_unique and key in self.columns:
if self.columns.nlevels > 1:
return self._getitem_multilevel(key)
return self._get_item_cache(key)
except (TypeError, ValueError):
# The TypeError correctly catches non hashable "key" (e.g. list)
# The ValueError can be removed once GH #21729 is fixed
pass
# Do we have a slicer (on rows)?
indexer = convert_to_index_sliceable(self, key)
if indexer is not None:
return self._slice(indexer, axis=0)
# Do we have a (boolean) DataFrame?
if isinstance(key, DataFrame):
return self._getitem_frame(key)
# Do we have a (boolean) 1d indexer?
if com.is_bool_indexer(key):
return self._getitem_bool_array(key)
# We are left with two options: a single key, and a collection of keys,
# We interpret tuples as collections only for non-MultiIndex
is_single_key = isinstance(key, tuple) or not is_list_like(key)
if is_single_key:
if self.columns.nlevels > 1:
return self._getitem_multilevel(key)
indexer = self.columns.get_loc(key)
if is_integer(indexer):
indexer = [indexer]
else:
if is_iterator(key):
key = list(key)
# noinspection PyProtectedMember
indexer = self.loc._convert_to_indexer(key, axis=1, raise_missing=True)
# take() does not accept boolean indexers
if getattr(indexer, "dtype", None) == bool:
indexer = np.where(indexer)[0]
data = self._take(indexer, axis=1)
if is_single_key:
# What does looking for a single key in a non-unique index return?
# The behavior is inconsistent. It returns a Series, except when
# - the key itself is repeated (test on data.shape, #9519), or
# - we have a MultiIndex on columns (test on self.columns, #21309)
if data.shape[1] == 1 and not isinstance(self.columns, MultiIndex):
data = data[key]
return data
def _try_cast(
arr, dtype: Optional[DtypeObj], copy: bool, raise_cast_failure: bool,
):
"""
Convert input to numpy ndarray and optionally cast to a given dtype.
Parameters
----------
arr : ndarray, list, tuple, iterator (catchall)
Excludes: ExtensionArray, Series, Index.
dtype : np.dtype, ExtensionDtype or None
copy : bool
If False, don't copy the data if not needed.
raise_cast_failure : bool
If True, and if a dtype is specified, raise errors during casting.
Otherwise an object array is returned.
"""
# perf shortcut as this is the most common case
if isinstance(arr, np.ndarray):
if maybe_castable(arr) and not copy and dtype is None:
return arr
try:
# GH#15832: Check if we are requesting a numeric dype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
subarr = maybe_cast_to_integer_array(arr, dtype)
subarr = maybe_cast_to_datetime(arr, dtype)
# Take care in creating object arrays (but iterators are not
# supported):
if is_object_dtype(dtype) and (
is_list_like(subarr)
and not (is_iterator(subarr) or isinstance(subarr, np.ndarray))
):
subarr = construct_1d_object_array_from_listlike(subarr)
elif not is_extension_array_dtype(subarr):
subarr = construct_1d_ndarray_preserving_na(subarr, dtype, copy=copy)
except OutOfBoundsDatetime:
# in case of out of bound datetime64 -> always raise
raise
except (ValueError, TypeError):
if is_categorical_dtype(dtype):
# We *do* allow casting to categorical, since we know
# that Categorical is the only array type for 'category'.
dtype = cast(CategoricalDtype, dtype)
subarr = dtype.construct_array_type()(
arr, dtype.categories, ordered=dtype.ordered
)
elif is_extension_array_dtype(dtype):
# create an extension array from its dtype
dtype = cast(ExtensionDtype, dtype)
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
elif dtype is not None and raise_cast_failure:
raise
else:
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
def __getitem__(self, key):
"""
The rebuilt method of __getitem__, which will redirect the DataFrame and Series to OneData and OneSeries.
"""
key = lib.item_from_zerodim(key)
key = com.apply_if_callable(key, self)
if is_hashable(key):
if self.columns.is_unique and key in self.columns:
if self.columns.nlevels > 1:
return OneSeries(self._getitem_multilevel(key))
return OneSeries(self._get_item_cache(key))
indexer = convert_to_index_sliceable(self, key)
if indexer is not None:
return OneData(self._slice(indexer, axis=0))
if isinstance(key, DataFrame) or isinstance(key, OneData):
return self.where(key)
if com.is_bool_indexer(key):
return OneData(self._getitem_bool_array(key))
is_single_key = isinstance(key, tuple) or not is_list_like(key)
if is_single_key:
if self.columns.nlevels > 1:
return self._getitem_multilevel(key)
indexer = self.columns.get_loc(key)
if is_integer(indexer):
indexer = [indexer]
else:
if is_iterator(key):
key = list(key)
indexer = self.loc._get_listlike_indexer(key,
axis=1,
raise_missing=True)[1]
if getattr(indexer, "dtype", None) == bool:
indexer = np.where(indexer)[0]
data = self._take_with_is_copy(indexer, axis=1)
if is_single_key:
if data.shape[1] == 1 and not isinstance(self.columns,
ABCMultiIndex):
data = data[key]
return OneData(data)
def _try_cast(arr, take_fast_path, dtype, copy, raise_cast_failure):
# perf shortcut as this is the most common case
if take_fast_path:
if maybe_castable(arr) and not copy and dtype is None:
return arr
try:
# GH#15832: Check if we are requesting a numeric dype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
subarr = maybe_cast_to_integer_array(arr, dtype)
subarr = maybe_cast_to_datetime(arr, dtype)
# Take care in creating object arrays (but iterators are not
# supported):
if is_object_dtype(dtype) and (
is_list_like(subarr) and
not (is_iterator(subarr) or isinstance(subarr, np.ndarray))):
subarr = construct_1d_object_array_from_listlike(subarr)
elif not is_extension_type(subarr):
subarr = construct_1d_ndarray_preserving_na(subarr,
dtype,
copy=copy)
except OutOfBoundsDatetime:
# in case of out of bound datetime64 -> always raise
raise
except (ValueError, TypeError):
if is_categorical_dtype(dtype):
# We *do* allow casting to categorical, since we know
# that Categorical is the only array type for 'category'.
subarr = Categorical(arr, dtype.categories, ordered=dtype.ordered)
elif is_extension_array_dtype(dtype):
# create an extension array from its dtype
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
elif dtype is not None and raise_cast_failure:
raise
else:
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
def _try_cast(arr, take_fast_path, dtype, copy, raise_cast_failure):
# perf shortcut as this is the most common case
if take_fast_path:
if maybe_castable(arr) and not copy and dtype is None:
return arr
try:
# GH#15832: Check if we are requesting a numeric dype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
subarr = maybe_cast_to_integer_array(arr, dtype)
subarr = maybe_cast_to_datetime(arr, dtype)
# Take care in creating object arrays (but iterators are not
# supported):
if is_object_dtype(dtype) and (is_list_like(subarr) and
not (is_iterator(subarr) or
isinstance(subarr, np.ndarray))):
subarr = construct_1d_object_array_from_listlike(subarr)
elif not is_extension_type(subarr):
subarr = construct_1d_ndarray_preserving_na(subarr, dtype,
copy=copy)
except (ValueError, TypeError):
if is_categorical_dtype(dtype):
# We *do* allow casting to categorical, since we know
# that Categorical is the only array type for 'category'.
subarr = Categorical(arr, dtype.categories,
ordered=dtype.ordered)
elif is_extension_array_dtype(dtype):
# create an extension array from its dtype
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
elif dtype is not None and raise_cast_failure:
raise
else:
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
def _parse_errorbars(self, label, err):
"""
Look for error keyword arguments and return the actual errorbar data
or return the error DataFrame/dict
Error bars can be specified in several ways:
Series: the user provides a pandas.Series object of the same
length as the data
ndarray: provides a np.ndarray of the same length as the data
DataFrame/dict: error values are paired with keys matching the
key in the plotted DataFrame
str: the name of the column within the plotted DataFrame
"""
if err is None:
return None
def match_labels(data, e):
e = e.reindex(data.index)
return e
# key-matched DataFrame
if isinstance(err, ABCDataFrame):
err = match_labels(self.data, err)
# key-matched dict
elif isinstance(err, dict):
pass
# Series of error values
elif isinstance(err, ABCSeries):
# broadcast error series across data
err = match_labels(self.data, err)
err = np.atleast_2d(err)
err = np.tile(err, (self.nseries, 1))
# errors are a column in the dataframe
elif isinstance(err, str):
evalues = self.data[err].values
self.data = self.data[self.data.columns.drop(err)]
err = np.atleast_2d(evalues)
err = np.tile(err, (self.nseries, 1))
elif is_list_like(err):
if is_iterator(err):
err = np.atleast_2d(list(err))
else:
# raw error values
err = np.atleast_2d(err)
err_shape = err.shape
# asymmetrical error bars
if err.ndim == 3:
if ((err_shape[0] != self.nseries) or (err_shape[1] != 2)
or (err_shape[2] != len(self.data))):
msg = ("Asymmetrical error bars should be provided " +
"with the shape (%u, 2, %u)" %
(self.nseries, len(self.data)))
raise ValueError(msg)
# broadcast errors to each data series
if len(err) == 1:
err = np.tile(err, (self.nseries, 1))
elif is_number(err):
err = np.tile([err], (self.nseries, len(self.data)))
else:
msg = "No valid {label} detected".format(label=label)
raise ValueError(msg)
return err
