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 _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 _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, scalar, 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
if isinstance(dtype, ExtensionDtype) and dtype.kind != "M":
# create an extension array from its dtype
# DatetimeTZ case needs to go through maybe_cast_to_datetime
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
return subarr
try:
# GH#15832: Check if we are requesting a numeric dtype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
# this will raise if we have e.g. floats
maybe_cast_to_integer_array(arr, dtype)
subarr = arr
else:
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 dtype is not None and raise_cast_failure:
raise
else:
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
def ndarray_to_mgr(values, index, columns, dtype: Optional[DtypeObj],
copy: bool, typ: str) -> Manager:
# used in DataFrame.__init__
# input must be a ndarray, list, Series, Index, ExtensionArray
if isinstance(values, ABCSeries):
if columns is None:
if values.name is not None:
columns = Index([values.name])
if index is None:
index = values.index
else:
values = values.reindex(index)
# zero len case (GH #2234)
if not len(values) and columns is not None and len(columns):
values = np.empty((0, 1), dtype=object)
if is_extension_array_dtype(values) or is_extension_array_dtype(dtype):
# GH#19157
if isinstance(values, np.ndarray) and values.ndim > 1:
# GH#12513 a EA dtype passed with a 2D array, split into
# multiple EAs that view the values
values = [values[:, n] for n in range(values.shape[1])]
else:
values = [values]
if columns is None:
columns = Index(range(len(values)))
return arrays_to_mgr(values,
columns,
index,
columns,
dtype=dtype,
typ=typ)
# by definition an array here
# the dtypes will be coerced to a single dtype
values = _prep_ndarray(values, copy=copy)
if dtype is not None and not is_dtype_equal(values.dtype, dtype):
shape = values.shape
flat = values.ravel()
if not is_integer_dtype(dtype):
# TODO: skipping integer_dtype is needed to keep the tests passing,
# not clear it is correct
# Note: we really only need _try_cast, but keeping to exposed funcs
values = sanitize_array(flat,
None,
dtype=dtype,
copy=copy,
raise_cast_failure=True)
else:
try:
values = construct_1d_ndarray_preserving_na(flat,
dtype=dtype,
copy=False)
except Exception as err:
# e.g. ValueError when trying to cast object dtype to float64
msg = f"failed to cast to '{dtype}' (Exception was: {err})"
raise ValueError(msg) from err
values = values.reshape(shape)
# _prep_ndarray ensures that values.ndim == 2 at this point
index, columns = _get_axes(values.shape[0],
values.shape[1],
index=index,
columns=columns)
values = values.T
# if we don't have a dtype specified, then try to convert objects
# on the entire block; this is to convert if we have datetimelike's
# embedded in an object type
if dtype is None and is_object_dtype(values.dtype):
if values.ndim == 2 and values.shape[0] != 1:
# transpose and separate blocks
dvals_list = [maybe_infer_to_datetimelike(row) for row in values]
dvals_list = [ensure_block_shape(dval, 2) for dval in dvals_list]
# TODO: What about re-joining object columns?
dvals_list = [maybe_squeeze_dt64tz(x) for x in dvals_list]
block_values = [
new_block(dvals_list[n], placement=n, ndim=2)
for n in range(len(dvals_list))
]
else:
datelike_vals = maybe_infer_to_datetimelike(values)
datelike_vals = maybe_squeeze_dt64tz(datelike_vals)
block_values = [datelike_vals]
else:
block_values = [maybe_squeeze_dt64tz(values)]
return create_block_manager_from_blocks(block_values, [columns, index])
def init_ndarray(values, index, columns, dtype: Optional[DtypeObj], copy: bool):
# input must be a ndarray, list, Series, index
if isinstance(values, ABCSeries):
if columns is None:
if values.name is not None:
columns = [values.name]
if index is None:
index = values.index
else:
values = values.reindex(index)
# zero len case (GH #2234)
if not len(values) and columns is not None and len(columns):
values = np.empty((0, 1), dtype=object)
if is_extension_array_dtype(values) or is_extension_array_dtype(dtype):
# GH#19157
if isinstance(values, np.ndarray) and values.ndim > 1:
# GH#12513 a EA dtype passed with a 2D array, split into
# multiple EAs that view the values
values = [values[:, n] for n in range(values.shape[1])]
else:
values = [values]
if columns is None:
columns = Index(range(len(values)))
return arrays_to_mgr(values, columns, index, columns, dtype=dtype)
# by definition an array here
# the dtypes will be coerced to a single dtype
values = _prep_ndarray(values, copy=copy)
if dtype is not None and not is_dtype_equal(values.dtype, dtype):
try:
values = construct_1d_ndarray_preserving_na(
values.ravel(), dtype=dtype, copy=False
).reshape(values.shape)
except Exception as orig:
# e.g. ValueError when trying to cast object dtype to float64
raise ValueError(
f"failed to cast to '{dtype}' (Exception was: {orig})"
) from orig
# _prep_ndarray ensures that values.ndim == 2 at this point
index, columns = _get_axes(
values.shape[0], values.shape[1], index=index, columns=columns
)
values = values.T
# if we don't have a dtype specified, then try to convert objects
# on the entire block; this is to convert if we have datetimelike's
# embedded in an object type
if dtype is None and is_object_dtype(values.dtype):
if values.ndim == 2 and values.shape[0] != 1:
# transpose and separate blocks
dvals_list = [maybe_infer_to_datetimelike(row) for row in values]
for n in range(len(dvals_list)):
if isinstance(dvals_list[n], np.ndarray):
dvals_list[n] = dvals_list[n].reshape(1, -1)
from pandas.core.internals.blocks import make_block
# TODO: What about re-joining object columns?
block_values = [
make_block(dvals_list[n], placement=[n], ndim=2)
for n in range(len(dvals_list))
]
else:
datelike_vals = maybe_infer_to_datetimelike(values)
block_values = [datelike_vals]
else:
block_values = [values]
return create_block_manager_from_blocks(block_values, [columns, index])
def test_construct_1d_ndarray_preserving_na(values, dtype, expected):
result = construct_1d_ndarray_preserving_na(values, dtype=dtype)
tm.assert_numpy_array_equal(result, expected)
def ndarray_to_mgr(values, index, columns, dtype: DtypeObj | None, copy: bool,
typ: str) -> Manager:
# used in DataFrame.__init__
# input must be a ndarray, list, Series, Index, ExtensionArray
if isinstance(values, ABCSeries):
if columns is None:
if values.name is not None:
columns = Index([values.name])
if index is None:
index = values.index
else:
values = values.reindex(index)
# zero len case (GH #2234)
if not len(values) and columns is not None and len(columns):
values = np.empty((0, 1), dtype=object)
vdtype = getattr(values, "dtype", None)
if is_1d_only_ea_dtype(vdtype) or isinstance(dtype, ExtensionDtype):
# GH#19157
if isinstance(values, np.ndarray) and values.ndim > 1:
# GH#12513 a EA dtype passed with a 2D array, split into
# multiple EAs that view the values
values = [values[:, n] for n in range(values.shape[1])]
else:
values = [values]
if columns is None:
columns = Index(range(len(values)))
return arrays_to_mgr(values,
columns,
index,
columns,
dtype=dtype,
typ=typ)
if is_extension_array_dtype(vdtype) and not is_1d_only_ea_dtype(vdtype):
# i.e. Datetime64TZ
values = extract_array(values, extract_numpy=True)
if copy:
values = values.copy()
if values.ndim == 1:
values = values.reshape(-1, 1)
else:
# by definition an array here
# the dtypes will be coerced to a single dtype
values = _prep_ndarray(values, copy=copy)
if dtype is not None and not is_dtype_equal(values.dtype, dtype):
shape = values.shape
flat = values.ravel()
if not is_integer_dtype(dtype):
# TODO: skipping integer_dtype is needed to keep the tests passing,
# not clear it is correct
# Note: we really only need _try_cast, but keeping to exposed funcs
values = sanitize_array(flat,
None,
dtype=dtype,
copy=copy,
raise_cast_failure=True)
else:
try:
values = construct_1d_ndarray_preserving_na(flat,
dtype=dtype,
copy=False)
except IntCastingNaNError:
# following Series, we ignore the dtype and retain floating
# values instead of casting nans to meaningless ints
pass
values = values.reshape(shape)
# _prep_ndarray ensures that values.ndim == 2 at this point
index, columns = _get_axes(values.shape[0],
values.shape[1],
index=index,
columns=columns)
_check_values_indices_shape_match(values, index, columns)
if typ == "array":
if issubclass(values.dtype.type, str):
values = np.array(values, dtype=object)
if dtype is None and is_object_dtype(values.dtype):
arrays = [
ensure_wrapped_if_datetimelike(
maybe_infer_to_datetimelike(values[:, i].copy()))
for i in range(values.shape[1])
]
else:
if is_datetime_or_timedelta_dtype(values.dtype):
values = ensure_wrapped_if_datetimelike(values)
arrays = [values[:, i].copy() for i in range(values.shape[1])]
return ArrayManager(arrays, [index, columns], verify_integrity=False)
values = values.T
# if we don't have a dtype specified, then try to convert objects
# on the entire block; this is to convert if we have datetimelike's
# embedded in an object type
if dtype is None and is_object_dtype(values.dtype):
if values.ndim == 2 and values.shape[0] != 1:
# transpose and separate blocks
dtlike_vals = [maybe_infer_to_datetimelike(row) for row in values]
dvals_list = [ensure_block_shape(dval, 2) for dval in dtlike_vals]
# TODO: What about re-joining object columns?
block_values = [
new_block(dvals_list[n], placement=n, ndim=2)
for n in range(len(dvals_list))
]
else:
datelike_vals = maybe_infer_to_datetimelike(values)
nb = new_block(datelike_vals,
placement=slice(len(columns)),
ndim=2)
block_values = [nb]
else:
nb = new_block(values, placement=slice(len(columns)), ndim=2)
block_values = [nb]
if len(columns) == 0:
block_values = []
return create_block_manager_from_blocks(block_values, [columns, index])
def _try_cast(
arr: list | np.ndarray,
dtype: DtypeObj | None,
copy: bool,
raise_cast_failure: bool,
) -> ArrayLike:
"""
Convert input to numpy ndarray and optionally cast to a given dtype.
Parameters
----------
arr : ndarray or list
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.
Returns
-------
np.ndarray or ExtensionArray
"""
# perf shortcut as this is the most common case
if (isinstance(arr, np.ndarray) and maybe_castable(arr.dtype) and not copy
and dtype is None):
return arr
if isinstance(dtype,
ExtensionDtype) and not isinstance(dtype, DatetimeTZDtype):
# create an extension array from its dtype
# DatetimeTZ case needs to go through maybe_cast_to_datetime but
# SparseDtype does not
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
return subarr
if is_object_dtype(dtype) and not isinstance(arr, np.ndarray):
subarr = construct_1d_object_array_from_listlike(arr)
return subarr
try:
# GH#15832: Check if we are requesting a numeric dtype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
# this will raise if we have e.g. floats
# error: Argument 2 to "maybe_cast_to_integer_array" has incompatible type
# "Union[dtype, ExtensionDtype, None]"; expected "Union[ExtensionDtype, str,
# dtype, Type[str], Type[float], Type[int], Type[complex], Type[bool],
# Type[object]]"
maybe_cast_to_integer_array(arr, dtype) # type: ignore[arg-type]
subarr = arr
else:
subarr = maybe_cast_to_datetime(arr, dtype)
if dtype is not None and dtype.kind == "M":
return subarr
if not isinstance(subarr, ABCExtensionArray):
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) as err:
if dtype is not None and raise_cast_failure:
raise
elif "Cannot cast" in str(err):
# via _disallow_mismatched_datetimelike
raise
else:
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
def test_construct_1d_ndarray_preserving_na(values, dtype, expected):
result = construct_1d_ndarray_preserving_na(values, dtype=dtype)
tm.assert_numpy_array_equal(result, expected)
def _try_cast(
arr: list | np.ndarray,
dtype: DtypeObj | None,
copy: bool,
raise_cast_failure: bool,
) -> ArrayLike:
"""
Convert input to numpy ndarray and optionally cast to a given dtype.
Parameters
----------
arr : ndarray or list
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.
Returns
-------
np.ndarray or ExtensionArray
"""
is_ndarray = isinstance(arr, np.ndarray)
if dtype is None:
# perf shortcut as this is the most common case
if is_ndarray:
arr = cast(np.ndarray, arr)
if arr.dtype != object:
return sanitize_to_nanoseconds(arr, copy=copy)
out = maybe_infer_to_datetimelike(arr)
if out is arr and copy:
out = out.copy()
return out
else:
# i.e. list
varr = np.array(arr, copy=False)
# filter out cases that we _dont_ want to go through
# maybe_infer_to_datetimelike
if varr.dtype != object or varr.size == 0:
return varr
return maybe_infer_to_datetimelike(varr)
elif isinstance(dtype, ExtensionDtype):
# create an extension array from its dtype
if isinstance(dtype, DatetimeTZDtype):
# We can't go through _from_sequence because it handles dt64naive
# data differently; _from_sequence treats naive as wall times,
# while maybe_cast_to_datetime treats it as UTC
# see test_maybe_promote_any_numpy_dtype_with_datetimetz
return maybe_cast_to_datetime(arr, dtype)
# TODO: copy?
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
return subarr
elif is_object_dtype(dtype):
if not is_ndarray:
subarr = construct_1d_object_array_from_listlike(arr)
return subarr
return ensure_wrapped_if_datetimelike(arr).astype(dtype, copy=copy)
elif dtype.kind in ["m", "M"]:
return maybe_cast_to_datetime(arr, dtype)
try:
# GH#15832: Check if we are requesting a numeric dtype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
# this will raise if we have e.g. floats
maybe_cast_to_integer_array(arr, dtype)
subarr = arr
else:
subarr = arr
if not isinstance(subarr, ABCExtensionArray):
# 4 tests fail if we move this to a try/except/else; see
# test_constructor_compound_dtypes, test_constructor_cast_failure
# test_constructor_dict_cast2, test_loc_setitem_dtype
subarr = construct_1d_ndarray_preserving_na(subarr,
dtype,
copy=copy)
except (ValueError, TypeError):
if raise_cast_failure:
raise
else:
# we only get here with raise_cast_failure False, which means
# called via the DataFrame constructor
# GH#24435
warnings.warn(
f"Could not cast to {dtype}, falling back to object. This "
"behavior is deprecated. In a future version, when a dtype is "
"passed to 'DataFrame', either all columns will be cast to that "
"dtype, or a TypeError will be raised",
FutureWarning,
stacklevel=7,
)
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
def _try_cast(
arr: list | np.ndarray,
dtype: DtypeObj | None,
copy: bool,
raise_cast_failure: bool,
) -> ArrayLike:
"""
Convert input to numpy ndarray and optionally cast to a given dtype.
Parameters
----------
arr : ndarray or list
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.
Returns
-------
np.ndarray or ExtensionArray
"""
is_ndarray = isinstance(arr, np.ndarray)
# perf shortcut as this is the most common case
# Item "List[Any]" of "Union[List[Any], ndarray]" has no attribute "dtype"
if (is_ndarray and arr.dtype != object # type: ignore[union-attr]
and not copy and dtype is None):
# Argument 1 to "sanitize_to_nanoseconds" has incompatible type
# "Union[List[Any], ndarray]"; expected "ndarray"
return sanitize_to_nanoseconds(arr) # type: ignore[arg-type]
if isinstance(dtype, ExtensionDtype):
# create an extension array from its dtype
# DatetimeTZ case needs to go through maybe_cast_to_datetime but
# SparseDtype does not
if isinstance(dtype, DatetimeTZDtype):
# We can't go through _from_sequence because it handles dt64naive
# data differently; _from_sequence treats naive as wall times,
# while maybe_cast_to_datetime treats it as UTC
# see test_maybe_promote_any_numpy_dtype_with_datetimetz
# error: Incompatible return value type (got "Union[ExtensionArray,
# ndarray, List[Any]]", expected "Union[ExtensionArray, ndarray]")
return maybe_cast_to_datetime(arr,
dtype) # type: ignore[return-value]
# TODO: copy?
array_type = dtype.construct_array_type()._from_sequence
subarr = array_type(arr, dtype=dtype, copy=copy)
return subarr
elif is_object_dtype(dtype):
if not is_ndarray:
subarr = construct_1d_object_array_from_listlike(arr)
return subarr
return ensure_wrapped_if_datetimelike(arr).astype(dtype, copy=copy)
elif dtype is None and not is_ndarray:
# filter out cases that we _dont_ want to go through maybe_cast_to_datetime
varr = np.array(arr, copy=False)
if varr.dtype != object or varr.size == 0:
return varr
# error: Incompatible return value type (got "Union[ExtensionArray,
# ndarray, List[Any]]", expected "Union[ExtensionArray, ndarray]")
return maybe_cast_to_datetime(varr, None) # type: ignore[return-value]
try:
# GH#15832: Check if we are requesting a numeric dtype and
# that we can convert the data to the requested dtype.
if is_integer_dtype(dtype):
# this will raise if we have e.g. floats
dtype = cast(np.dtype, dtype)
maybe_cast_to_integer_array(arr, dtype)
subarr = arr
else:
subarr = maybe_cast_to_datetime(arr, dtype)
if dtype is not None and dtype.kind == "M":
return subarr
if not isinstance(subarr, ABCExtensionArray):
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) as err:
if dtype is not None and raise_cast_failure:
raise
elif "Cannot cast" in str(err):
# via _disallow_mismatched_datetimelike
raise
else:
subarr = np.array(arr, dtype=object, copy=copy)
return subarr
