def test_is_number(self): self.assertTrue(is_number(True)) self.assertTrue(is_number(1)) self.assertTrue(is_number(1.1)) self.assertTrue(is_number(1 + 3j)) self.assertTrue(is_number(np.bool(False))) self.assertTrue(is_number(np.int64(1))) self.assertTrue(is_number(np.float64(1.1))) self.assertTrue(is_number(np.complex128(1 + 3j))) self.assertTrue(is_number(np.nan)) self.assertFalse(is_number(None)) self.assertFalse(is_number('x')) self.assertFalse(is_number(datetime(2011, 1, 1))) self.assertFalse(is_number(np.datetime64('2011-01-01'))) self.assertFalse(is_number(Timestamp('2011-01-01'))) self.assertFalse(is_number(Timestamp('2011-01-01', tz='US/Eastern'))) self.assertFalse(is_number(timedelta(1000))) self.assertFalse(is_number(Timedelta('1 days'))) # questionable self.assertFalse(is_number(np.bool_(False))) self.assertTrue(is_number(np.timedelta64(1, 'D')))
def to_numeric(arg, errors='raise', downcast=None): """ Convert argument to a numeric type. Parameters ---------- arg : list, tuple, 1-d array, or Series errors : {'ignore', 'raise', 'coerce'}, default 'raise' - If 'raise', then invalid parsing will raise an exception - If 'coerce', then invalid parsing will be set as NaN - If 'ignore', then invalid parsing will return the input downcast : {'integer', 'signed', 'unsigned', 'float'} , default None If not None, and if the data has been successfully cast to a numerical dtype (or if the data was numeric to begin with), downcast that resulting data to the smallest numerical dtype possible according to the following rules: - 'integer' or 'signed': smallest signed int dtype (min.: np.int8) - 'unsigned': smallest unsigned int dtype (min.: np.uint8) - 'float': smallest float dtype (min.: np.float32) As this behaviour is separate from the core conversion to numeric values, any errors raised during the downcasting will be surfaced regardless of the value of the 'errors' input. In addition, downcasting will only occur if the size of the resulting data's dtype is strictly larger than the dtype it is to be cast to, so if none of the dtypes checked satisfy that specification, no downcasting will be performed on the data. .. versionadded:: 0.19.0 Returns ------- ret : numeric if parsing succeeded. Return type depends on input. Series if Series, otherwise ndarray Examples -------- Take separate series and convert to numeric, coercing when told to >>> import pandas as pd >>> s = pd.Series(['1.0', '2', -3]) >>> pd.to_numeric(s) 0 1.0 1 2.0 2 -3.0 dtype: float64 >>> pd.to_numeric(s, downcast='float') 0 1.0 1 2.0 2 -3.0 dtype: float32 >>> pd.to_numeric(s, downcast='signed') 0 1 1 2 2 -3 dtype: int8 >>> s = pd.Series(['apple', '1.0', '2', -3]) >>> pd.to_numeric(s, errors='ignore') 0 apple 1 1.0 2 2 3 -3 dtype: object >>> pd.to_numeric(s, errors='coerce') 0 NaN 1 1.0 2 2.0 3 -3.0 dtype: float64 """ if downcast not in (None, 'integer', 'signed', 'unsigned', 'float'): raise ValueError('invalid downcasting method provided') is_series = False is_index = False is_scalar = False if isinstance(arg, pd.Series): is_series = True values = arg.values elif isinstance(arg, pd.Index): is_index = True values = arg.asi8 if values is None: values = arg.values elif isinstance(arg, (list, tuple)): values = np.array(arg, dtype='O') elif np.isscalar(arg): if is_number(arg): return arg is_scalar = True values = np.array([arg], dtype='O') elif getattr(arg, 'ndim', 1) > 1: raise TypeError('arg must be a list, tuple, 1-d array, or Series') else: values = arg try: if is_numeric_dtype(values): pass elif is_datetime_or_timedelta_dtype(values): values = values.astype(np.int64) else: values = _ensure_object(values) coerce_numeric = False if errors in ('ignore', 'raise') else True values = lib.maybe_convert_numeric(values, set(), coerce_numeric=coerce_numeric) except Exception: if errors == 'raise': raise # attempt downcast only if the data has been successfully converted # to a numerical dtype and if a downcast method has been specified if downcast is not None and is_numeric_dtype(values): typecodes = None if downcast in ('integer', 'signed'): typecodes = np.typecodes['Integer'] elif downcast == 'unsigned' and np.min(values) > 0: typecodes = np.typecodes['UnsignedInteger'] elif downcast == 'float': typecodes = np.typecodes['Float'] # pandas support goes only to np.float32, # as float dtypes smaller than that are # extremely rare and not well supported float_32_char = np.dtype(np.float32).char float_32_ind = typecodes.index(float_32_char) typecodes = typecodes[float_32_ind:] if typecodes is not None: # from smallest to largest for dtype in typecodes: if np.dtype(dtype).itemsize < values.dtype.itemsize: values = _possibly_downcast_to_dtype(values, dtype) # successful conversion if values.dtype == dtype: break if is_series: return pd.Series(values, index=arg.index, name=arg.name) elif is_index: # because we want to coerce to numeric if possible, # do not use _shallow_copy_with_infer return Index(values, name=arg.name) elif is_scalar: return values[0] else: return values
def _check_as_is(x): return (self.quoting == csv.QUOTE_NONNUMERIC and is_number(x)) or isinstance(x, str)
def to_numeric(arg, errors='raise', downcast=None): """ Convert argument to a numeric type. Parameters ---------- arg : list, tuple, 1-d array, or Series errors : {'ignore', 'raise', 'coerce'}, default 'raise' - If 'raise', then invalid parsing will raise an exception - If 'coerce', then invalid parsing will be set as NaN - If 'ignore', then invalid parsing will return the input downcast : {'integer', 'signed', 'unsigned', 'float'} , default None If not None, and if the data has been successfully cast to a numerical dtype (or if the data was numeric to begin with), downcast that resulting data to the smallest numerical dtype possible according to the following rules: - 'integer' or 'signed': smallest signed int dtype (min.: np.int8) - 'unsigned': smallest unsigned int dtype (min.: np.uint8) - 'float': smallest float dtype (min.: np.float32) As this behaviour is separate from the core conversion to numeric values, any errors raised during the downcasting will be surfaced regardless of the value of the 'errors' input. In addition, downcasting will only occur if the size of the resulting data's dtype is strictly larger than the dtype it is to be cast to, so if none of the dtypes checked satisfy that specification, no downcasting will be performed on the data. .. versionadded:: 0.19.0 Returns ------- ret : numeric if parsing succeeded. Return type depends on input. Series if Series, otherwise ndarray Examples -------- Take separate series and convert to numeric, coercing when told to >>> import pandas as pd >>> s = pd.Series(['1.0', '2', -3]) >>> pd.to_numeric(s) 0 1.0 1 2.0 2 -3.0 dtype: float64 >>> pd.to_numeric(s, downcast='float') 0 1.0 1 2.0 2 -3.0 dtype: float32 >>> pd.to_numeric(s, downcast='signed') 0 1 1 2 2 -3 dtype: int8 >>> s = pd.Series(['apple', '1.0', '2', -3]) >>> pd.to_numeric(s, errors='ignore') 0 apple 1 1.0 2 2 3 -3 dtype: object >>> pd.to_numeric(s, errors='coerce') 0 NaN 1 1.0 2 2.0 3 -3.0 dtype: float64 """ if downcast not in (None, 'integer', 'signed', 'unsigned', 'float'): raise ValueError('invalid downcasting method provided') is_series = False is_index = False is_scalar = False if isinstance(arg, pd.Series): is_series = True values = arg.values elif isinstance(arg, pd.Index): is_index = True values = arg.asi8 if values is None: values = arg.values elif isinstance(arg, (list, tuple)): values = np.array(arg, dtype='O') elif np.isscalar(arg): if is_number(arg): return arg is_scalar = True values = np.array([arg], dtype='O') elif getattr(arg, 'ndim', 1) > 1: raise TypeError('arg must be a list, tuple, 1-d array, or Series') else: values = arg try: if is_numeric_dtype(values): pass elif is_datetime_or_timedelta_dtype(values): values = values.astype(np.int64) else: values = _ensure_object(values) coerce_numeric = False if errors in ('ignore', 'raise') else True values = lib.maybe_convert_numeric(values, set(), coerce_numeric=coerce_numeric) except Exception: if errors == 'raise': raise # attempt downcast only if the data has been successfully converted # to a numerical dtype and if a downcast method has been specified if downcast is not None and is_numeric_dtype(values): typecodes = None if downcast in ('integer', 'signed'): typecodes = np.typecodes['Integer'] elif downcast == 'unsigned' and np.min(values) > 0: typecodes = np.typecodes['UnsignedInteger'] elif downcast == 'float': typecodes = np.typecodes['Float'] # pandas support goes only to np.float32, # as float dtypes smaller than that are # extremely rare and not well supported float_32_char = np.dtype(np.float32).char float_32_ind = typecodes.index(float_32_char) typecodes = typecodes[float_32_ind:] if typecodes is not None: # from smallest to largest for dtype in typecodes: if np.dtype(dtype).itemsize < values.dtype.itemsize: values = _possibly_downcast_to_dtype( values, dtype) # successful conversion if values.dtype == dtype: break if is_series: return pd.Series(values, index=arg.index, name=arg.name) elif is_index: # because we want to coerce to numeric if possible, # do not use _shallow_copy_with_infer return Index(values, name=arg.name) elif is_scalar: return values[0] else: return values