def test_min_max_empty(self, skipna): arr = TimedeltaArray._from_sequence([]) result = arr.min(skipna=skipna) assert result is pd.NaT result = arr.max(skipna=skipna) assert result is pd.NaT
def test_astype_int(self, dtype): arr = TimedeltaArray._from_sequence( [pd.Timedelta('1H'), pd.Timedelta('2H')]) result = arr.astype(dtype) if np.dtype(dtype).kind == 'u': expected_dtype = np.dtype('uint64') else: expected_dtype = np.dtype('int64') expected = arr.astype(expected_dtype) assert result.dtype == expected_dtype tm.assert_numpy_array_equal(result, expected)
def test_astype_int(self, dtype): arr = TimedeltaArray._from_sequence([pd.Timedelta('1H'), pd.Timedelta('2H')]) result = arr.astype(dtype) if np.dtype(dtype).kind == 'u': expected_dtype = np.dtype('uint64') else: expected_dtype = np.dtype('int64') expected = arr.astype(expected_dtype) assert result.dtype == expected_dtype tm.assert_numpy_array_equal(result, expected)
def test_min_max(self): arr = TimedeltaArray._from_sequence([ '3H', '3H', 'NaT', '2H', '5H', '4H', ]) result = arr.min() expected = pd.Timedelta('2H') assert result == expected result = arr.max() expected = pd.Timedelta('5H') assert result == expected result = arr.min(skipna=False) assert result is pd.NaT result = arr.max(skipna=False) assert result is pd.NaT
def array(data, # type: Sequence[object] dtype=None, # type: Optional[Union[str, np.dtype, ExtensionDtype]] copy=True, # type: bool ): # type: (...) -> ExtensionArray """ Create an array. .. versionadded:: 0.24.0 Parameters ---------- data : Sequence of objects The scalars inside `data` should be instances of the scalar type for `dtype`. It's expected that `data` represents a 1-dimensional array of data. When `data` is an Index or Series, the underlying array will be extracted from `data`. dtype : str, np.dtype, or ExtensionDtype, optional The dtype to use for the array. This may be a NumPy dtype or an extension type registered with pandas using :meth:`pandas.api.extensions.register_extension_dtype`. If not specified, there are two possibilities: 1. When `data` is a :class:`Series`, :class:`Index`, or :class:`ExtensionArray`, the `dtype` will be taken from the data. 2. Otherwise, pandas will attempt to infer the `dtype` from the data. Note that when `data` is a NumPy array, ``data.dtype`` is *not* used for inferring the array type. This is because NumPy cannot represent all the types of data that can be held in extension arrays. Currently, pandas will infer an extension dtype for sequences of ============================== ===================================== scalar type Array Type ============================= ===================================== * :class:`pandas.Interval` :class:`pandas.IntervalArray` * :class:`pandas.Period` :class:`pandas.arrays.PeriodArray` * :class:`datetime.datetime` :class:`pandas.arrays.DatetimeArray` * :class:`datetime.timedelta` :class:`pandas.arrays.TimedeltaArray` ============================= ===================================== For all other cases, NumPy's usual inference rules will be used. copy : bool, default True Whether to copy the data, even if not necessary. Depending on the type of `data`, creating the new array may require copying data, even if ``copy=False``. Returns ------- ExtensionArray The newly created array. Raises ------ ValueError When `data` is not 1-dimensional. See Also -------- numpy.array : Construct a NumPy array. arrays.PandasArray : ExtensionArray wrapping a NumPy array. Series : Construct a pandas Series. Index : Construct a pandas Index. Notes ----- Omitting the `dtype` argument means pandas will attempt to infer the best array type from the values in the data. As new array types are added by pandas and 3rd party libraries, the "best" array type may change. We recommend specifying `dtype` to ensure that 1. the correct array type for the data is returned 2. the returned array type doesn't change as new extension types are added by pandas and third-party libraries Additionally, if the underlying memory representation of the returned array matters, we recommend specifying the `dtype` as a concrete object rather than a string alias or allowing it to be inferred. For example, a future version of pandas or a 3rd-party library may include a dedicated ExtensionArray for string data. In this event, the following would no longer return a :class:`arrays.PandasArray` backed by a NumPy array. >>> pd.array(['a', 'b'], dtype=str) <PandasArray> ['a', 'b'] Length: 2, dtype: str32 This would instead return the new ExtensionArray dedicated for string data. If you really need the new array to be backed by a NumPy array, specify that in the dtype. >>> pd.array(['a', 'b'], dtype=np.dtype("<U1")) <PandasArray> ['a', 'b'] Length: 2, dtype: str32 Or use the dedicated constructor for the array you're expecting, and wrap that in a PandasArray >>> pd.array(np.array(['a', 'b'], dtype='<U1')) <PandasArray> ['a', 'b'] Length: 2, dtype: str32 Examples -------- If a dtype is not specified, `data` is passed through to :meth:`numpy.array`, and a :class:`arrays.PandasArray` is returned. >>> pd.array([1, 2]) <PandasArray> [1, 2] Length: 2, dtype: int64 Or the NumPy dtype can be specified >>> pd.array([1, 2], dtype=np.dtype("int32")) <PandasArray> [1, 2] Length: 2, dtype: int32 You can use the string alias for `dtype` >>> pd.array(['a', 'b', 'a'], dtype='category') [a, b, a] Categories (2, object): [a, b] Or specify the actual dtype >>> pd.array(['a', 'b', 'a'], ... dtype=pd.CategoricalDtype(['a', 'b', 'c'], ordered=True)) [a, b, a] Categories (3, object): [a < b < c] Because omitting the `dtype` passes the data through to NumPy, a mixture of valid integers and NA will return a floating-point NumPy array. >>> pd.array([1, 2, np.nan]) <PandasArray> [1.0, 2.0, nan] Length: 3, dtype: float64 To use pandas' nullable :class:`pandas.arrays.IntegerArray`, specify the dtype: >>> pd.array([1, 2, np.nan], dtype='Int64') <IntegerArray> [1, 2, NaN] Length: 3, dtype: Int64 Pandas will infer an ExtensionArray for some types of data: >>> pd.array([pd.Period('2000', freq="D"), pd.Period("2000", freq="D")]) <PeriodArray> ['2000-01-01', '2000-01-01'] Length: 2, dtype: period[D] `data` must be 1-dimensional. A ValueError is raised when the input has the wrong dimensionality. >>> pd.array(1) Traceback (most recent call last): ... ValueError: Cannot pass scalar '1' to 'pandas.array'. """ from pandas.core.arrays import ( period_array, ExtensionArray, IntervalArray, PandasArray, DatetimeArrayMixin, TimedeltaArrayMixin, ) from pandas.core.internals.arrays import extract_array if lib.is_scalar(data): msg = ( "Cannot pass scalar '{}' to 'pandas.array'." ) raise ValueError(msg.format(data)) data = extract_array(data, extract_numpy=True) if dtype is None and isinstance(data, ExtensionArray): dtype = data.dtype # this returns None for not-found dtypes. if isinstance(dtype, compat.string_types): dtype = registry.find(dtype) or dtype if is_extension_array_dtype(dtype): cls = dtype.construct_array_type() return cls._from_sequence(data, dtype=dtype, copy=copy) if dtype is None: inferred_dtype = lib.infer_dtype(data) if inferred_dtype == 'period': try: return period_array(data, copy=copy) except tslibs.IncompatibleFrequency: # We may have a mixture of frequencies. # We choose to return an ndarray, rather than raising. pass elif inferred_dtype == 'interval': try: return IntervalArray(data, copy=copy) except ValueError: # We may have a mixture of `closed` here. # We choose to return an ndarray, rather than raising. pass elif inferred_dtype.startswith('datetime'): # datetime, datetime64 try: return DatetimeArrayMixin._from_sequence(data, copy=copy) except ValueError: # Mixture of timezones, fall back to PandasArray pass elif inferred_dtype.startswith('timedelta'): # timedelta, timedelta64 return TimedeltaArrayMixin._from_sequence(data, copy=copy) # TODO(BooleanArray): handle this type result = PandasArray._from_sequence(data, dtype=dtype, copy=copy) return result
def test_from_sequence_dtype(self): msg = r"Only timedelta64\[ns\] dtype is valid" with pytest.raises(ValueError, match=msg): TimedeltaArray._from_sequence([], dtype=object) with pytest.raises(ValueError, match=msg): TimedeltaArray([], dtype=object)