ai-content-maker/.venv/Lib/site-packages/pandas/core/flags.py

116 lines
3.6 KiB
Python

from __future__ import annotations
import weakref
class Flags:
"""
Flags that apply to pandas objects.
.. versionadded:: 1.2.0
Parameters
----------
obj : Series or DataFrame
The object these flags are associated with.
allows_duplicate_labels : bool, default True
Whether to allow duplicate labels in this object. By default,
duplicate labels are permitted. Setting this to ``False`` will
cause an :class:`errors.DuplicateLabelError` to be raised when
`index` (or columns for DataFrame) is not unique, or any
subsequent operation on introduces duplicates.
See :ref:`duplicates.disallow` for more.
.. warning::
This is an experimental feature. Currently, many methods fail to
propagate the ``allows_duplicate_labels`` value. In future versions
it is expected that every method taking or returning one or more
DataFrame or Series objects will propagate ``allows_duplicate_labels``.
Notes
-----
Attributes can be set in two ways
>>> df = pd.DataFrame()
>>> df.flags
<Flags(allows_duplicate_labels=True)>
>>> df.flags.allows_duplicate_labels = False
>>> df.flags
<Flags(allows_duplicate_labels=False)>
>>> df.flags['allows_duplicate_labels'] = True
>>> df.flags
<Flags(allows_duplicate_labels=True)>
"""
_keys = {"allows_duplicate_labels"}
def __init__(self, obj, *, allows_duplicate_labels) -> None:
self._allows_duplicate_labels = allows_duplicate_labels
self._obj = weakref.ref(obj)
@property
def allows_duplicate_labels(self) -> bool:
"""
Whether this object allows duplicate labels.
Setting ``allows_duplicate_labels=False`` ensures that the
index (and columns of a DataFrame) are unique. Most methods
that accept and return a Series or DataFrame will propagate
the value of ``allows_duplicate_labels``.
See :ref:`duplicates` for more.
See Also
--------
DataFrame.attrs : Set global metadata on this object.
DataFrame.set_flags : Set global flags on this object.
Examples
--------
>>> df = pd.DataFrame({"A": [1, 2]}, index=['a', 'a'])
>>> df.flags.allows_duplicate_labels
True
>>> df.flags.allows_duplicate_labels = False
Traceback (most recent call last):
...
pandas.errors.DuplicateLabelError: Index has duplicates.
positions
label
a [0, 1]
"""
return self._allows_duplicate_labels
@allows_duplicate_labels.setter
def allows_duplicate_labels(self, value: bool) -> None:
value = bool(value)
obj = self._obj()
if obj is None:
raise ValueError("This flag's object has been deleted.")
if not value:
for ax in obj.axes:
ax._maybe_check_unique()
self._allows_duplicate_labels = value
def __getitem__(self, key):
if key not in self._keys:
raise KeyError(key)
return getattr(self, key)
def __setitem__(self, key, value) -> None:
if key not in self._keys:
raise ValueError(f"Unknown flag {key}. Must be one of {self._keys}")
setattr(self, key, value)
def __repr__(self) -> str:
return f"<Flags(allows_duplicate_labels={self.allows_duplicate_labels})>"
def __eq__(self, other):
if isinstance(other, type(self)):
return self.allows_duplicate_labels == other.allows_duplicate_labels
return False