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generic.py
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# pyright: reportPropertyTypeMismatch=false
from __future__ import annotations
import collections
from datetime import timedelta
import functools
import gc
import json
import operator
import pickle
import re
from typing import (
TYPE_CHECKING,
Any,
Callable,
ClassVar,
Hashable,
Iterator,
Literal,
Mapping,
NoReturn,
Sequence,
Type,
cast,
final,
overload,
)
import warnings
import weakref
import numpy as np
from pandas._config import config
from pandas._libs import lib
from pandas._libs.tslibs import (
Period,
Tick,
Timestamp,
to_offset,
)
from pandas._typing import (
AlignJoin,
AnyArrayLike,
ArrayLike,
Axis,
AxisInt,
ColspaceArgType,
CompressionOptions,
Dtype,
DtypeArg,
DtypeObj,
FilePath,
FillnaOptions,
FloatFormatType,
FormattersType,
Frequency,
IgnoreRaise,
IndexKeyFunc,
IndexLabel,
IntervalClosedType,
JSONSerializable,
Level,
Manager,
NaPosition,
NDFrameT,
RandomState,
Renamer,
SortKind,
StorageOptions,
Suffixes,
T,
TimeAmbiguous,
TimedeltaConvertibleTypes,
TimeNonexistent,
TimestampConvertibleTypes,
ValueKeyFunc,
WriteBuffer,
npt,
)
from pandas.compat._optional import import_optional_dependency
from pandas.compat.numpy import function as nv
from pandas.errors import (
AbstractMethodError,
InvalidIndexError,
SettingWithCopyError,
SettingWithCopyWarning,
)
from pandas.util._decorators import (
deprecate_kwarg,
deprecate_nonkeyword_arguments,
doc,
rewrite_axis_style_signature,
)
from pandas.util._exceptions import find_stack_level
from pandas.util._validators import (
validate_ascending,
validate_bool_kwarg,
validate_fillna_kwargs,
validate_inclusive,
)
from pandas.core.dtypes.common import (
ensure_object,
ensure_platform_int,
ensure_str,
is_bool,
is_bool_dtype,
is_datetime64_any_dtype,
is_datetime64tz_dtype,
is_dict_like,
is_dtype_equal,
is_extension_array_dtype,
is_float,
is_list_like,
is_number,
is_numeric_dtype,
is_re_compilable,
is_scalar,
is_timedelta64_dtype,
pandas_dtype,
)
from pandas.core.dtypes.generic import (
ABCDataFrame,
ABCSeries,
)
from pandas.core.dtypes.inference import (
is_hashable,
is_nested_list_like,
)
from pandas.core.dtypes.missing import (
isna,
notna,
)
from pandas.core import (
algorithms as algos,
arraylike,
common as com,
indexing,
missing,
nanops,
sample,
)
from pandas.core.array_algos.replace import should_use_regex
from pandas.core.arrays import ExtensionArray
from pandas.core.base import PandasObject
from pandas.core.construction import extract_array
from pandas.core.describe import describe_ndframe
from pandas.core.flags import Flags
from pandas.core.indexes.api import (
DatetimeIndex,
Index,
MultiIndex,
PeriodIndex,
RangeIndex,
default_index,
ensure_index,
)
from pandas.core.internals import (
ArrayManager,
BlockManager,
SingleArrayManager,
)
from pandas.core.internals.construction import mgr_to_mgr
from pandas.core.missing import find_valid_index
from pandas.core.ops import align_method_FRAME
from pandas.core.reshape.concat import concat
from pandas.core.shared_docs import _shared_docs
from pandas.core.sorting import get_indexer_indexer
from pandas.core.window import (
Expanding,
ExponentialMovingWindow,
Rolling,
Window,
)
from pandas.io.formats import format as fmt
from pandas.io.formats.format import (
DataFrameFormatter,
DataFrameRenderer,
)
from pandas.io.formats.printing import pprint_thing
if TYPE_CHECKING:
from pandas._libs.tslibs import BaseOffset
from pandas.core.frame import DataFrame
from pandas.core.indexers.objects import BaseIndexer
from pandas.core.resample import Resampler
from pandas.core.series import Series
from pandas.io.pytables import HDFStore
# goal is to be able to define the docs close to function, while still being
# able to share
_shared_docs = {**_shared_docs}
_shared_doc_kwargs = {
"axes": "keywords for axes",
"klass": "Series/DataFrame",
"axes_single_arg": "int or labels for object",
"args_transpose": "axes to permute (int or label for object)",
"inplace": """
inplace : bool, default False
If True, performs operation inplace and returns None.""",
"optional_by": """
by : str or list of str
Name or list of names to sort by""",
"replace_iloc": """
This differs from updating with ``.loc`` or ``.iloc``, which require
you to specify a location to update with some value.""",
}
bool_t = bool # Need alias because NDFrame has def bool:
class NDFrame(PandasObject, indexing.IndexingMixin):
"""
N-dimensional analogue of DataFrame. Store multi-dimensional in a
size-mutable, labeled data structure
Parameters
----------
data : BlockManager
axes : list
copy : bool, default False
"""
_internal_names: list[str] = [
"_mgr",
"_cacher",
"_item_cache",
"_cache",
"_is_copy",
"_subtyp",
"_name",
"_default_kind",
"_default_fill_value",
"_metadata",
"__array_struct__",
"__array_interface__",
"_flags",
]
_internal_names_set: set[str] = set(_internal_names)
_accessors: set[str] = set()
_hidden_attrs: frozenset[str] = frozenset(
["_AXIS_NAMES", "_AXIS_NUMBERS", "get_values"]
)
_metadata: list[str] = []
_is_copy: weakref.ReferenceType[NDFrame] | None = None
_mgr: Manager
_attrs: dict[Hashable, Any]
_typ: str
# ----------------------------------------------------------------------
# Constructors
def __init__(
self,
data: Manager,
copy: bool_t = False,
attrs: Mapping[Hashable, Any] | None = None,
) -> None:
# copy kwarg is retained for mypy compat, is not used
object.__setattr__(self, "_is_copy", None)
object.__setattr__(self, "_mgr", data)
object.__setattr__(self, "_item_cache", {})
if attrs is None:
attrs = {}
else:
attrs = dict(attrs)
object.__setattr__(self, "_attrs", attrs)
object.__setattr__(self, "_flags", Flags(self, allows_duplicate_labels=True))
@classmethod
def _init_mgr(
cls,
mgr: Manager,
axes,
dtype: Dtype | None = None,
copy: bool_t = False,
) -> Manager:
"""passed a manager and a axes dict"""
for a, axe in axes.items():
if axe is not None:
axe = ensure_index(axe)
bm_axis = cls._get_block_manager_axis(a)
mgr = mgr.reindex_axis(axe, axis=bm_axis)
# make a copy if explicitly requested
if copy:
mgr = mgr.copy()
if dtype is not None:
# avoid further copies if we can
if (
isinstance(mgr, BlockManager)
and len(mgr.blocks) == 1
and is_dtype_equal(mgr.blocks[0].values.dtype, dtype)
):
pass
else:
mgr = mgr.astype(dtype=dtype)
return mgr
def _as_manager(self: NDFrameT, typ: str, copy: bool_t = True) -> NDFrameT:
"""
Private helper function to create a DataFrame with specific manager.
Parameters
----------
typ : {"block", "array"}
copy : bool, default True
Only controls whether the conversion from Block->ArrayManager
copies the 1D arrays (to ensure proper/contiguous memory layout).
Returns
-------
DataFrame
New DataFrame using specified manager type. Is not guaranteed
to be a copy or not.
"""
new_mgr: Manager
new_mgr = mgr_to_mgr(self._mgr, typ=typ, copy=copy)
# fastpath of passing a manager doesn't check the option/manager class
return self._constructor(new_mgr).__finalize__(self)
# ----------------------------------------------------------------------
# attrs and flags
@property
def attrs(self) -> dict[Hashable, Any]:
"""
Dictionary of global attributes of this dataset.
.. warning::
attrs is experimental and may change without warning.
See Also
--------
DataFrame.flags : Global flags applying to this object.
"""
if self._attrs is None:
self._attrs = {}
return self._attrs
@attrs.setter
def attrs(self, value: Mapping[Hashable, Any]) -> None:
self._attrs = dict(value)
@final
@property
def flags(self) -> Flags:
"""
Get the properties associated with this pandas object.
The available flags are
* :attr:`Flags.allows_duplicate_labels`
See Also
--------
Flags : Flags that apply to pandas objects.
DataFrame.attrs : Global metadata applying to this dataset.
Notes
-----
"Flags" differ from "metadata". Flags reflect properties of the
pandas object (the Series or DataFrame). Metadata refer to properties
of the dataset, and should be stored in :attr:`DataFrame.attrs`.
Examples
--------
>>> df = pd.DataFrame({"A": [1, 2]})
>>> df.flags
<Flags(allows_duplicate_labels=True)>
Flags can be get or set using ``.``
>>> df.flags.allows_duplicate_labels
True
>>> df.flags.allows_duplicate_labels = False
Or by slicing with a key
>>> df.flags["allows_duplicate_labels"]
False
>>> df.flags["allows_duplicate_labels"] = True
"""
return self._flags
@final
def set_flags(
self: NDFrameT,
*,
copy: bool_t = False,
allows_duplicate_labels: bool_t | None = None,
) -> NDFrameT:
"""
Return a new object with updated flags.
Parameters
----------
allows_duplicate_labels : bool, optional
Whether the returned object allows duplicate labels.
Returns
-------
Series or DataFrame
The same type as the caller.
See Also
--------
DataFrame.attrs : Global metadata applying to this dataset.
DataFrame.flags : Global flags applying to this object.
Notes
-----
This method returns a new object that's a view on the same data
as the input. Mutating the input or the output values will be reflected
in the other.
This method is intended to be used in method chains.
"Flags" differ from "metadata". Flags reflect properties of the
pandas object (the Series or DataFrame). Metadata refer to properties
of the dataset, and should be stored in :attr:`DataFrame.attrs`.
Examples
--------
>>> df = pd.DataFrame({"A": [1, 2]})
>>> df.flags.allows_duplicate_labels
True
>>> df2 = df.set_flags(allows_duplicate_labels=False)
>>> df2.flags.allows_duplicate_labels
False
"""
df = self.copy(deep=copy)
if allows_duplicate_labels is not None:
df.flags["allows_duplicate_labels"] = allows_duplicate_labels
return df
@final
@classmethod
def _validate_dtype(cls, dtype) -> DtypeObj | None:
"""validate the passed dtype"""
if dtype is not None:
dtype = pandas_dtype(dtype)
# a compound dtype
if dtype.kind == "V":
raise NotImplementedError(
"compound dtypes are not implemented "
f"in the {cls.__name__} constructor"
)
return dtype
# ----------------------------------------------------------------------
# Construction
@property
def _constructor(self: NDFrameT) -> Callable[..., NDFrameT]:
"""
Used when a manipulation result has the same dimensions as the
original.
"""
raise AbstractMethodError(self)
# ----------------------------------------------------------------------
# Internals
@final
@property
def _data(self):
# GH#33054 retained because some downstream packages uses this,
# e.g. fastparquet
return self._mgr
# ----------------------------------------------------------------------
# Axis
_stat_axis_number = 0
_stat_axis_name = "index"
_AXIS_ORDERS: list[Literal["index", "columns"]]
_AXIS_TO_AXIS_NUMBER: dict[Axis, AxisInt] = {0: 0, "index": 0, "rows": 0}
_info_axis_number: int
_info_axis_name: Literal["index", "columns"]
_AXIS_LEN: int
@final
def _construct_axes_dict(self, axes: Sequence[Axis] | None = None, **kwargs):
"""Return an axes dictionary for myself."""
d = {a: self._get_axis(a) for a in (axes or self._AXIS_ORDERS)}
# error: Argument 1 to "update" of "MutableMapping" has incompatible type
# "Dict[str, Any]"; expected "SupportsKeysAndGetItem[Union[int, str], Any]"
d.update(kwargs) # type: ignore[arg-type]
return d
@final
@classmethod
def _construct_axes_from_arguments(
cls, args, kwargs, require_all: bool_t = False, sentinel=None
):
"""
Construct and returns axes if supplied in args/kwargs.
If require_all, raise if all axis arguments are not supplied
return a tuple of (axes, kwargs).
sentinel specifies the default parameter when an axis is not
supplied; useful to distinguish when a user explicitly passes None
in scenarios where None has special meaning.
"""
# construct the args
args = list(args)
for a in cls._AXIS_ORDERS:
# look for a argument by position
if a not in kwargs:
try:
kwargs[a] = args.pop(0)
except IndexError as err:
if require_all:
raise TypeError(
"not enough/duplicate arguments specified!"
) from err
axes = {a: kwargs.pop(a, sentinel) for a in cls._AXIS_ORDERS}
return axes, kwargs
@final
@classmethod
def _get_axis_number(cls, axis: Axis) -> AxisInt:
try:
return cls._AXIS_TO_AXIS_NUMBER[axis]
except KeyError:
raise ValueError(f"No axis named {axis} for object type {cls.__name__}")
@final
@classmethod
def _get_axis_name(cls, axis: Axis) -> Literal["index", "columns"]:
axis_number = cls._get_axis_number(axis)
return cls._AXIS_ORDERS[axis_number]
@final
def _get_axis(self, axis: Axis) -> Index:
axis_number = self._get_axis_number(axis)
assert axis_number in {0, 1}
return self.index if axis_number == 0 else self.columns
@final
@classmethod
def _get_block_manager_axis(cls, axis: Axis) -> AxisInt:
"""Map the axis to the block_manager axis."""
axis = cls._get_axis_number(axis)
ndim = cls._AXIS_LEN
if ndim == 2:
# i.e. DataFrame
return 1 - axis
return axis
@final
def _get_axis_resolvers(self, axis: str) -> dict[str, Series | MultiIndex]:
# index or columns
axis_index = getattr(self, axis)
d = {}
prefix = axis[0]
for i, name in enumerate(axis_index.names):
if name is not None:
key = level = name
else:
# prefix with 'i' or 'c' depending on the input axis
# e.g., you must do ilevel_0 for the 0th level of an unnamed
# multiiindex
key = f"{prefix}level_{i}"
level = i
level_values = axis_index.get_level_values(level)
s = level_values.to_series()
s.index = axis_index
d[key] = s
# put the index/columns itself in the dict
if isinstance(axis_index, MultiIndex):
dindex = axis_index
else:
dindex = axis_index.to_series()
d[axis] = dindex
return d
@final
def _get_index_resolvers(self) -> dict[Hashable, Series | MultiIndex]:
from pandas.core.computation.parsing import clean_column_name
d: dict[str, Series | MultiIndex] = {}
for axis_name in self._AXIS_ORDERS:
d.update(self._get_axis_resolvers(axis_name))
return {clean_column_name(k): v for k, v in d.items() if not isinstance(k, int)}
@final
def _get_cleaned_column_resolvers(self) -> dict[Hashable, Series]:
"""
Return the special character free column resolvers of a dataframe.
Column names with special characters are 'cleaned up' so that they can
be referred to by backtick quoting.
Used in :meth:`DataFrame.eval`.
"""
from pandas.core.computation.parsing import clean_column_name
if isinstance(self, ABCSeries):
return {clean_column_name(self.name): self}
return {
clean_column_name(k): v for k, v in self.items() if not isinstance(k, int)
}
@property
def _info_axis(self) -> Index:
return getattr(self, self._info_axis_name)
@property
def _stat_axis(self) -> Index:
return getattr(self, self._stat_axis_name)
@property
def shape(self) -> tuple[int, ...]:
"""
Return a tuple of axis dimensions
"""
return tuple(len(self._get_axis(a)) for a in self._AXIS_ORDERS)
@property
def axes(self) -> list[Index]:
"""
Return index label(s) of the internal NDFrame
"""
# we do it this way because if we have reversed axes, then
# the block manager shows then reversed
return [self._get_axis(a) for a in self._AXIS_ORDERS]
@property
def ndim(self) -> int:
"""
Return an int representing the number of axes / array dimensions.
Return 1 if Series. Otherwise return 2 if DataFrame.
See Also
--------
ndarray.ndim : Number of array dimensions.
Examples
--------
>>> s = pd.Series({'a': 1, 'b': 2, 'c': 3})
>>> s.ndim
1
>>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
>>> df.ndim
2
"""
return self._mgr.ndim
@property
def size(self) -> int:
"""
Return an int representing the number of elements in this object.
Return the number of rows if Series. Otherwise return the number of
rows times number of columns if DataFrame.
See Also
--------
ndarray.size : Number of elements in the array.
Examples
--------
>>> s = pd.Series({'a': 1, 'b': 2, 'c': 3})
>>> s.size
3
>>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
>>> df.size
4
"""
# error: Incompatible return value type (got "signedinteger[_64Bit]",
# expected "int") [return-value]
return np.prod(self.shape) # type: ignore[return-value]
def set_axis(
self: NDFrameT,
labels,
*,
axis: Axis = 0,
copy: bool_t = True,
) -> NDFrameT:
"""
Assign desired index to given axis.
Indexes for%(extended_summary_sub)s row labels can be changed by assigning
a list-like or Index.
Parameters
----------
labels : list-like, Index
The values for the new index.
axis : %(axes_single_arg)s, default 0
The axis to update. The value 0 identifies the rows. For `Series`
this parameter is unused and defaults to 0.
copy : bool, default True
Whether to make a copy of the underlying data.
.. versionadded:: 1.5.0
Returns
-------
renamed : %(klass)s
An object of type %(klass)s.
See Also
--------
%(klass)s.rename_axis : Alter the name of the index%(see_also_sub)s.
"""
return self._set_axis_nocheck(labels, axis, inplace=False, copy=copy)
@final
def _set_axis_nocheck(self, labels, axis: Axis, inplace: bool_t, copy: bool_t):
if inplace:
setattr(self, self._get_axis_name(axis), labels)
else:
# With copy=False, we create a new object but don't copy the
# underlying data.
obj = self.copy(deep=copy)
setattr(obj, obj._get_axis_name(axis), labels)
return obj
@final
def _set_axis(self, axis: AxisInt, labels: AnyArrayLike | list) -> None:
"""
This is called from the cython code when we set the `index` attribute
directly, e.g. `series.index = [1, 2, 3]`.
"""
labels = ensure_index(labels)
self._mgr.set_axis(axis, labels)
self._clear_item_cache()
@final
def swapaxes(
self: NDFrameT, axis1: Axis, axis2: Axis, copy: bool_t = True
) -> NDFrameT:
"""
Interchange axes and swap values axes appropriately.
Returns
-------
y : same as input
"""
i = self._get_axis_number(axis1)
j = self._get_axis_number(axis2)
if i == j:
if copy:
return self.copy()
return self
mapping = {i: j, j: i}
new_axes = (self._get_axis(mapping.get(k, k)) for k in range(self._AXIS_LEN))
new_values = self.values.swapaxes(i, j)
if copy:
new_values = new_values.copy()
return self._constructor(
new_values,
*new_axes,
).__finalize__(self, method="swapaxes")
@final
@doc(klass=_shared_doc_kwargs["klass"])
def droplevel(self: NDFrameT, level: IndexLabel, axis: Axis = 0) -> NDFrameT:
"""
Return {klass} with requested index / column level(s) removed.
Parameters
----------
level : int, str, or list-like
If a string is given, must be the name of a level
If list-like, elements must be names or positional indexes
of levels.
axis : {{0 or 'index', 1 or 'columns'}}, default 0
Axis along which the level(s) is removed:
* 0 or 'index': remove level(s) in column.
* 1 or 'columns': remove level(s) in row.
For `Series` this parameter is unused and defaults to 0.
Returns
-------
{klass}
{klass} with requested index / column level(s) removed.
Examples
--------
>>> df = pd.DataFrame([
... [1, 2, 3, 4],
... [5, 6, 7, 8],
... [9, 10, 11, 12]
... ]).set_index([0, 1]).rename_axis(['a', 'b'])
>>> df.columns = pd.MultiIndex.from_tuples([
... ('c', 'e'), ('d', 'f')
... ], names=['level_1', 'level_2'])
>>> df
level_1 c d
level_2 e f
a b
1 2 3 4
5 6 7 8
9 10 11 12
>>> df.droplevel('a')
level_1 c d
level_2 e f
b
2 3 4
6 7 8
10 11 12
>>> df.droplevel('level_2', axis=1)
level_1 c d
a b
1 2 3 4
5 6 7 8
9 10 11 12
"""
labels = self._get_axis(axis)
new_labels = labels.droplevel(level)
return self.set_axis(new_labels, axis=axis)
def pop(self, item: Hashable) -> Series | Any:
result = self[item]
del self[item]
return result
@final
def squeeze(self, axis: Axis | None = None):
"""
Squeeze 1 dimensional axis objects into scalars.
Series or DataFrames with a single element are squeezed to a scalar.
DataFrames with a single column or a single row are squeezed to a
Series. Otherwise the object is unchanged.
This method is most useful when you don't know if your
object is a Series or DataFrame, but you do know it has just a single
column. In that case you can safely call `squeeze` to ensure you have a
Series.
Parameters
----------
axis : {0 or 'index', 1 or 'columns', None}, default None
A specific axis to squeeze. By default, all length-1 axes are
squeezed. For `Series` this parameter is unused and defaults to `None`.
Returns
-------
DataFrame, Series, or scalar
The projection after squeezing `axis` or all the axes.
See Also
--------
Series.iloc : Integer-location based indexing for selecting scalars.
DataFrame.iloc : Integer-location based indexing for selecting Series.
Series.to_frame : Inverse of DataFrame.squeeze for a
single-column DataFrame.
Examples
--------
>>> primes = pd.Series([2, 3, 5, 7])
Slicing might produce a Series with a single value:
>>> even_primes = primes[primes % 2 == 0]
>>> even_primes
0 2
dtype: int64
>>> even_primes.squeeze()
2
Squeezing objects with more than one value in every axis does nothing:
>>> odd_primes = primes[primes % 2 == 1]
>>> odd_primes
1 3
2 5
3 7
dtype: int64
>>> odd_primes.squeeze()
1 3
2 5
3 7
dtype: int64
Squeezing is even more effective when used with DataFrames.
>>> df = pd.DataFrame([[1, 2], [3, 4]], columns=['a', 'b'])
>>> df
a b
0 1 2
1 3 4
Slicing a single column will produce a DataFrame with the columns
having only one value:
>>> df_a = df[['a']]
>>> df_a
a
0 1
1 3
So the columns can be squeezed down, resulting in a Series:
>>> df_a.squeeze('columns')
0 1
1 3
Name: a, dtype: int64
Slicing a single row from a single column will produce a single
scalar DataFrame:
>>> df_0a = df.loc[df.index < 1, ['a']]
>>> df_0a
a
0 1
Squeezing the rows produces a single scalar Series:
>>> df_0a.squeeze('rows')
a 1
Name: 0, dtype: int64
Squeezing all axes will project directly into a scalar:
>>> df_0a.squeeze()
1
"""
axes = range(self._AXIS_LEN) if axis is None else (self._get_axis_number(axis),)
return self.iloc[
tuple(
0 if i in axes and len(a) == 1 else slice(None)
for i, a in enumerate(self.axes)
)
]
# ----------------------------------------------------------------------
# Rename
def _rename(
self: NDFrameT,
mapper: Renamer | None = None,
*,
index: Renamer | None = None,
columns: Renamer | None = None,
axis: Axis | None = None,
copy: bool_t | None = None,
inplace: bool_t = False,
level: Level | None = None,
errors: str = "ignore",
) -> NDFrameT | None:
# called by Series.rename and DataFrame.rename
if mapper is None and index is None and columns is None:
raise TypeError("must pass an index to rename")
if index is not None or columns is not None:
if axis is not None:
raise TypeError(
"Cannot specify both 'axis' and any of 'index' or 'columns'"
)
elif mapper is not None:
raise TypeError(
"Cannot specify both 'mapper' and any of 'index' or 'columns'"
)
else: