projektAI/venv/Lib/site-packages/pandas/core/arrays/boolean.py
2021-06-06 22:13:05 +02:00

723 lines
22 KiB
Python

import numbers
from typing import TYPE_CHECKING, List, Tuple, Type, Union
import warnings
import numpy as np
from pandas._libs import lib, missing as libmissing
from pandas._typing import ArrayLike
from pandas.compat.numpy import function as nv
from pandas.core.dtypes.common import (
is_bool_dtype,
is_extension_array_dtype,
is_float,
is_float_dtype,
is_integer_dtype,
is_list_like,
is_numeric_dtype,
pandas_dtype,
)
from pandas.core.dtypes.dtypes import register_extension_dtype
from pandas.core.dtypes.missing import isna
from pandas.core import ops
from .masked import BaseMaskedArray, BaseMaskedDtype
if TYPE_CHECKING:
import pyarrow
@register_extension_dtype
class BooleanDtype(BaseMaskedDtype):
"""
Extension dtype for boolean data.
.. versionadded:: 1.0.0
.. warning::
BooleanDtype is considered experimental. The implementation and
parts of the API may change without warning.
Attributes
----------
None
Methods
-------
None
Examples
--------
>>> pd.BooleanDtype()
BooleanDtype
"""
name = "boolean"
# mypy: https://github.com/python/mypy/issues/4125
@property
def type(self) -> Type: # type: ignore[override]
return np.bool_
@property
def kind(self) -> str:
return "b"
@property
def numpy_dtype(self) -> np.dtype:
return np.dtype("bool")
@classmethod
def construct_array_type(cls) -> Type["BooleanArray"]:
"""
Return the array type associated with this dtype.
Returns
-------
type
"""
return BooleanArray
def __repr__(self) -> str:
return "BooleanDtype"
@property
def _is_boolean(self) -> bool:
return True
@property
def _is_numeric(self) -> bool:
return True
def __from_arrow__(
self, array: Union["pyarrow.Array", "pyarrow.ChunkedArray"]
) -> "BooleanArray":
"""
Construct BooleanArray from pyarrow Array/ChunkedArray.
"""
import pyarrow
if isinstance(array, pyarrow.Array):
chunks = [array]
else:
# pyarrow.ChunkedArray
chunks = array.chunks
results = []
for arr in chunks:
# TODO should optimize this without going through object array
bool_arr = BooleanArray._from_sequence(np.array(arr))
results.append(bool_arr)
return BooleanArray._concat_same_type(results)
def coerce_to_array(
values, mask=None, copy: bool = False
) -> Tuple[np.ndarray, np.ndarray]:
"""
Coerce the input values array to numpy arrays with a mask.
Parameters
----------
values : 1D list-like
mask : bool 1D array, optional
copy : bool, default False
if True, copy the input
Returns
-------
tuple of (values, mask)
"""
if isinstance(values, BooleanArray):
if mask is not None:
raise ValueError("cannot pass mask for BooleanArray input")
values, mask = values._data, values._mask
if copy:
values = values.copy()
mask = mask.copy()
return values, mask
mask_values = None
if isinstance(values, np.ndarray) and values.dtype == np.bool_:
if copy:
values = values.copy()
elif isinstance(values, np.ndarray) and is_numeric_dtype(values.dtype):
mask_values = isna(values)
values_bool = np.zeros(len(values), dtype=bool)
values_bool[~mask_values] = values[~mask_values].astype(bool)
if not np.all(
values_bool[~mask_values].astype(values.dtype) == values[~mask_values]
):
raise TypeError("Need to pass bool-like values")
values = values_bool
else:
values_object = np.asarray(values, dtype=object)
inferred_dtype = lib.infer_dtype(values_object, skipna=True)
integer_like = ("floating", "integer", "mixed-integer-float")
if inferred_dtype not in ("boolean", "empty") + integer_like:
raise TypeError("Need to pass bool-like values")
mask_values = isna(values_object)
values = np.zeros(len(values), dtype=bool)
values[~mask_values] = values_object[~mask_values].astype(bool)
# if the values were integer-like, validate it were actually 0/1's
if (inferred_dtype in integer_like) and not (
np.all(
values[~mask_values].astype(float)
== values_object[~mask_values].astype(float)
)
):
raise TypeError("Need to pass bool-like values")
if mask is None and mask_values is None:
mask = np.zeros(len(values), dtype=bool)
elif mask is None:
mask = mask_values
else:
if isinstance(mask, np.ndarray) and mask.dtype == np.bool_:
if mask_values is not None:
mask = mask | mask_values
else:
if copy:
mask = mask.copy()
else:
mask = np.array(mask, dtype=bool)
if mask_values is not None:
mask = mask | mask_values
if values.ndim != 1:
raise ValueError("values must be a 1D list-like")
if mask.ndim != 1:
raise ValueError("mask must be a 1D list-like")
return values, mask
class BooleanArray(BaseMaskedArray):
"""
Array of boolean (True/False) data with missing values.
This is a pandas Extension array for boolean data, under the hood
represented by 2 numpy arrays: a boolean array with the data and
a boolean array with the mask (True indicating missing).
BooleanArray implements Kleene logic (sometimes called three-value
logic) for logical operations. See :ref:`boolean.kleene` for more.
To construct an BooleanArray from generic array-like input, use
:func:`pandas.array` specifying ``dtype="boolean"`` (see examples
below).
.. versionadded:: 1.0.0
.. warning::
BooleanArray is considered experimental. The implementation and
parts of the API may change without warning.
Parameters
----------
values : numpy.ndarray
A 1-d boolean-dtype array with the data.
mask : numpy.ndarray
A 1-d boolean-dtype array indicating missing values (True
indicates missing).
copy : bool, default False
Whether to copy the `values` and `mask` arrays.
Attributes
----------
None
Methods
-------
None
Returns
-------
BooleanArray
Examples
--------
Create an BooleanArray with :func:`pandas.array`:
>>> pd.array([True, False, None], dtype="boolean")
<BooleanArray>
[True, False, <NA>]
Length: 3, dtype: boolean
"""
# The value used to fill '_data' to avoid upcasting
_internal_fill_value = False
def __init__(self, values: np.ndarray, mask: np.ndarray, copy: bool = False):
if not (isinstance(values, np.ndarray) and values.dtype == np.bool_):
raise TypeError(
"values should be boolean numpy array. Use "
"the 'pd.array' function instead"
)
self._dtype = BooleanDtype()
super().__init__(values, mask, copy=copy)
@property
def dtype(self) -> BooleanDtype:
return self._dtype
@classmethod
def _from_sequence(
cls, scalars, *, dtype=None, copy: bool = False
) -> "BooleanArray":
if dtype:
assert dtype == "boolean"
values, mask = coerce_to_array(scalars, copy=copy)
return BooleanArray(values, mask)
@classmethod
def _from_sequence_of_strings(
cls, strings: List[str], *, dtype=None, copy: bool = False
) -> "BooleanArray":
def map_string(s):
if isna(s):
return s
elif s in ["True", "TRUE", "true", "1", "1.0"]:
return True
elif s in ["False", "FALSE", "false", "0", "0.0"]:
return False
else:
raise ValueError(f"{s} cannot be cast to bool")
scalars = [map_string(x) for x in strings]
return cls._from_sequence(scalars, dtype=dtype, copy=copy)
_HANDLED_TYPES = (np.ndarray, numbers.Number, bool, np.bool_)
def __array_ufunc__(self, ufunc, method: str, *inputs, **kwargs):
# For BooleanArray inputs, we apply the ufunc to ._data
# and mask the result.
if method == "reduce":
# Not clear how to handle missing values in reductions. Raise.
raise NotImplementedError("The 'reduce' method is not supported.")
out = kwargs.get("out", ())
for x in inputs + out:
if not isinstance(x, self._HANDLED_TYPES + (BooleanArray,)):
return NotImplemented
# for binary ops, use our custom dunder methods
result = ops.maybe_dispatch_ufunc_to_dunder_op(
self, ufunc, method, *inputs, **kwargs
)
if result is not NotImplemented:
return result
mask = np.zeros(len(self), dtype=bool)
inputs2 = []
for x in inputs:
if isinstance(x, BooleanArray):
mask |= x._mask
inputs2.append(x._data)
else:
inputs2.append(x)
def reconstruct(x):
# we don't worry about scalar `x` here, since we
# raise for reduce up above.
if is_bool_dtype(x.dtype):
m = mask.copy()
return BooleanArray(x, m)
else:
x[mask] = np.nan
return x
result = getattr(ufunc, method)(*inputs2, **kwargs)
if isinstance(result, tuple):
tuple(reconstruct(x) for x in result)
else:
return reconstruct(result)
def _coerce_to_array(self, value) -> Tuple[np.ndarray, np.ndarray]:
return coerce_to_array(value)
def astype(self, dtype, copy: bool = True) -> ArrayLike:
"""
Cast to a NumPy array or ExtensionArray with 'dtype'.
Parameters
----------
dtype : str or dtype
Typecode or data-type to which the array is cast.
copy : bool, default True
Whether to copy the data, even if not necessary. If False,
a copy is made only if the old dtype does not match the
new dtype.
Returns
-------
ndarray or ExtensionArray
NumPy ndarray, BooleanArray or IntegerArray with 'dtype' for its dtype.
Raises
------
TypeError
if incompatible type with an BooleanDtype, equivalent of same_kind
casting
"""
from pandas.core.arrays.string_ import StringDtype
dtype = pandas_dtype(dtype)
if isinstance(dtype, BooleanDtype):
values, mask = coerce_to_array(self, copy=copy)
if not copy:
return self
else:
return BooleanArray(values, mask, copy=False)
elif isinstance(dtype, StringDtype):
return dtype.construct_array_type()._from_sequence(self, copy=False)
if is_bool_dtype(dtype):
# astype_nansafe converts np.nan to True
if self._hasna:
raise ValueError("cannot convert float NaN to bool")
else:
return self._data.astype(dtype, copy=copy)
if is_extension_array_dtype(dtype) and is_integer_dtype(dtype):
from pandas.core.arrays import IntegerArray
return IntegerArray(
self._data.astype(dtype.numpy_dtype), self._mask.copy(), copy=False
)
# for integer, error if there are missing values
if is_integer_dtype(dtype) and self._hasna:
raise ValueError("cannot convert NA to integer")
# for float dtype, ensure we use np.nan before casting (numpy cannot
# deal with pd.NA)
na_value = self._na_value
if is_float_dtype(dtype):
na_value = np.nan
# coerce
return self.to_numpy(dtype=dtype, na_value=na_value, copy=False)
def _values_for_argsort(self) -> np.ndarray:
"""
Return values for sorting.
Returns
-------
ndarray
The transformed values should maintain the ordering between values
within the array.
See Also
--------
ExtensionArray.argsort : Return the indices that would sort this array.
"""
data = self._data.copy()
data[self._mask] = -1
return data
def any(self, *, skipna: bool = True, **kwargs):
"""
Return whether any element is True.
Returns False unless there is at least one element that is True.
By default, NAs are skipped. If ``skipna=False`` is specified and
missing values are present, similar :ref:`Kleene logic <boolean.kleene>`
is used as for logical operations.
Parameters
----------
skipna : bool, default True
Exclude NA values. If the entire array is NA and `skipna` is
True, then the result will be False, as for an empty array.
If `skipna` is False, the result will still be True if there is
at least one element that is True, otherwise NA will be returned
if there are NA's present.
**kwargs : any, default None
Additional keywords have no effect but might be accepted for
compatibility with NumPy.
Returns
-------
bool or :attr:`pandas.NA`
See Also
--------
numpy.any : Numpy version of this method.
BooleanArray.all : Return whether all elements are True.
Examples
--------
The result indicates whether any element is True (and by default
skips NAs):
>>> pd.array([True, False, True]).any()
True
>>> pd.array([True, False, pd.NA]).any()
True
>>> pd.array([False, False, pd.NA]).any()
False
>>> pd.array([], dtype="boolean").any()
False
>>> pd.array([pd.NA], dtype="boolean").any()
False
With ``skipna=False``, the result can be NA if this is logically
required (whether ``pd.NA`` is True or False influences the result):
>>> pd.array([True, False, pd.NA]).any(skipna=False)
True
>>> pd.array([False, False, pd.NA]).any(skipna=False)
<NA>
"""
kwargs.pop("axis", None)
nv.validate_any((), kwargs)
values = self._data.copy()
np.putmask(values, self._mask, False)
result = values.any()
if skipna:
return result
else:
if result or len(self) == 0 or not self._mask.any():
return result
else:
return self.dtype.na_value
def all(self, *, skipna: bool = True, **kwargs):
"""
Return whether all elements are True.
Returns True unless there is at least one element that is False.
By default, NAs are skipped. If ``skipna=False`` is specified and
missing values are present, similar :ref:`Kleene logic <boolean.kleene>`
is used as for logical operations.
Parameters
----------
skipna : bool, default True
Exclude NA values. If the entire array is NA and `skipna` is
True, then the result will be True, as for an empty array.
If `skipna` is False, the result will still be False if there is
at least one element that is False, otherwise NA will be returned
if there are NA's present.
**kwargs : any, default None
Additional keywords have no effect but might be accepted for
compatibility with NumPy.
Returns
-------
bool or :attr:`pandas.NA`
See Also
--------
numpy.all : Numpy version of this method.
BooleanArray.any : Return whether any element is True.
Examples
--------
The result indicates whether any element is True (and by default
skips NAs):
>>> pd.array([True, True, pd.NA]).all()
True
>>> pd.array([True, False, pd.NA]).all()
False
>>> pd.array([], dtype="boolean").all()
True
>>> pd.array([pd.NA], dtype="boolean").all()
True
With ``skipna=False``, the result can be NA if this is logically
required (whether ``pd.NA`` is True or False influences the result):
>>> pd.array([True, True, pd.NA]).all(skipna=False)
<NA>
>>> pd.array([True, False, pd.NA]).all(skipna=False)
False
"""
kwargs.pop("axis", None)
nv.validate_all((), kwargs)
values = self._data.copy()
np.putmask(values, self._mask, True)
result = values.all()
if skipna:
return result
else:
if not result or len(self) == 0 or not self._mask.any():
return result
else:
return self.dtype.na_value
def _logical_method(self, other, op):
assert op.__name__ in {"or_", "ror_", "and_", "rand_", "xor", "rxor"}
other_is_booleanarray = isinstance(other, BooleanArray)
other_is_scalar = lib.is_scalar(other)
mask = None
if other_is_booleanarray:
other, mask = other._data, other._mask
elif is_list_like(other):
other = np.asarray(other, dtype="bool")
if other.ndim > 1:
raise NotImplementedError("can only perform ops with 1-d structures")
other, mask = coerce_to_array(other, copy=False)
elif isinstance(other, np.bool_):
other = other.item()
if other_is_scalar and other is not libmissing.NA and not lib.is_bool(other):
raise TypeError(
"'other' should be pandas.NA or a bool. "
f"Got {type(other).__name__} instead."
)
if not other_is_scalar and len(self) != len(other):
raise ValueError("Lengths must match to compare")
if op.__name__ in {"or_", "ror_"}:
result, mask = ops.kleene_or(self._data, other, self._mask, mask)
elif op.__name__ in {"and_", "rand_"}:
result, mask = ops.kleene_and(self._data, other, self._mask, mask)
elif op.__name__ in {"xor", "rxor"}:
result, mask = ops.kleene_xor(self._data, other, self._mask, mask)
return BooleanArray(result, mask)
def _cmp_method(self, other, op):
from pandas.arrays import FloatingArray, IntegerArray
if isinstance(other, (IntegerArray, FloatingArray)):
return NotImplemented
mask = None
if isinstance(other, BooleanArray):
other, mask = other._data, other._mask
elif is_list_like(other):
other = np.asarray(other)
if other.ndim > 1:
raise NotImplementedError("can only perform ops with 1-d structures")
if len(self) != len(other):
raise ValueError("Lengths must match to compare")
if other is libmissing.NA:
# numpy does not handle pd.NA well as "other" scalar (it returns
# a scalar False instead of an array)
result = np.zeros_like(self._data)
mask = np.ones_like(self._data)
else:
# numpy will show a DeprecationWarning on invalid elementwise
# comparisons, this will raise in the future
with warnings.catch_warnings():
warnings.filterwarnings("ignore", "elementwise", FutureWarning)
with np.errstate(all="ignore"):
result = op(self._data, other)
# nans propagate
if mask is None:
mask = self._mask.copy()
else:
mask = self._mask | mask
return BooleanArray(result, mask, copy=False)
def _arith_method(self, other, op):
mask = None
op_name = op.__name__
if isinstance(other, BooleanArray):
other, mask = other._data, other._mask
elif is_list_like(other):
other = np.asarray(other)
if other.ndim > 1:
raise NotImplementedError("can only perform ops with 1-d structures")
if len(self) != len(other):
raise ValueError("Lengths must match")
# nans propagate
if mask is None:
mask = self._mask
if other is libmissing.NA:
mask |= True
else:
mask = self._mask | mask
if other is libmissing.NA:
# if other is NA, the result will be all NA and we can't run the
# actual op, so we need to choose the resulting dtype manually
if op_name in {"floordiv", "rfloordiv", "mod", "rmod", "pow", "rpow"}:
dtype = "int8"
else:
dtype = "bool"
result = np.zeros(len(self._data), dtype=dtype)
else:
if op_name in {"pow", "rpow"} and isinstance(other, np.bool_):
# Avoid DeprecationWarning: In future, it will be an error
# for 'np.bool_' scalars to be interpreted as an index
other = bool(other)
with np.errstate(all="ignore"):
result = op(self._data, other)
# divmod returns a tuple
if op_name == "divmod":
div, mod = result
return (
self._maybe_mask_result(div, mask, other, "floordiv"),
self._maybe_mask_result(mod, mask, other, "mod"),
)
return self._maybe_mask_result(result, mask, other, op_name)
def _reduce(self, name: str, *, skipna: bool = True, **kwargs):
if name in {"any", "all"}:
return getattr(self, name)(skipna=skipna, **kwargs)
return super()._reduce(name, skipna=skipna, **kwargs)
def _maybe_mask_result(self, result, mask, other, op_name: str):
"""
Parameters
----------
result : array-like
mask : array-like bool
other : scalar or array-like
op_name : str
"""
# if we have a float operand we are by-definition
# a float result
# or our op is a divide
if (is_float_dtype(other) or is_float(other)) or (
op_name in ["rtruediv", "truediv"]
):
from pandas.core.arrays import FloatingArray
return FloatingArray(result, mask, copy=False)
elif is_bool_dtype(result):
return BooleanArray(result, mask, copy=False)
elif is_integer_dtype(result):
from pandas.core.arrays import IntegerArray
return IntegerArray(result, mask, copy=False)
else:
result[mask] = np.nan
return result