def maximum_sctype(t):
"""
Return the scalar type of highest precision of the same kind as the input.
Parameters
----------
t : dtype or dtype specifier
The input data type. This can be a `dtype` object or an object that
is convertible to a `dtype`.
Returns
-------
out : dtype
The highest precision data type of the same kind (`dtype.kind`) as `t`.
See Also
--------
obj2sctype, mintypecode, sctype2char
dtype
Examples
--------
>>> np.maximum_sctype(np.int)
<type 'numpy.int64'>
>>> np.maximum_sctype(np.uint8)
<type 'numpy.uint64'>
>>> np.maximum_sctype(np.complex)
<type 'numpy.complex192'>
>>> np.maximum_sctype(str)
<type 'numpy.string_'>
>>> np.maximum_sctype('i2')
<type 'numpy.int64'>
>>> np.maximum_sctype('f4')
<type 'numpy.float96'>
"""
g = obj2sctype(t)
if g is None:
return t
t = g
name = t.__name__
base, bits = _evalname(name)
if bits == 0:
return t
else:
return sctypes[base][-1]
python类complex()的实例源码
def sctype2char(sctype):
"""
Return the string representation of a scalar dtype.
Parameters
----------
sctype : scalar dtype or object
If a scalar dtype, the corresponding string character is
returned. If an object, `sctype2char` tries to infer its scalar type
and then return the corresponding string character.
Returns
-------
typechar : str
The string character corresponding to the scalar type.
Raises
------
ValueError
If `sctype` is an object for which the type can not be inferred.
See Also
--------
obj2sctype, issctype, issubsctype, mintypecode
Examples
--------
>>> for sctype in [np.int32, np.float, np.complex, np.string_, np.ndarray]:
... print(np.sctype2char(sctype))
l
d
D
S
O
>>> x = np.array([1., 2-1.j])
>>> np.sctype2char(x)
'D'
>>> np.sctype2char(list)
'O'
"""
sctype = obj2sctype(sctype)
if sctype is None:
raise ValueError("unrecognized type")
return _sctype2char_dict[sctype]
# Create dictionary of casting functions that wrap sequences
# indexed by type or type character
def _set_up_aliases():
type_pairs = [('complex_', 'cdouble'),
('int0', 'intp'),
('uint0', 'uintp'),
('single', 'float'),
('csingle', 'cfloat'),
('singlecomplex', 'cfloat'),
('float_', 'double'),
('intc', 'int'),
('uintc', 'uint'),
('int_', 'long'),
('uint', 'ulong'),
('cfloat', 'cdouble'),
('longfloat', 'longdouble'),
('clongfloat', 'clongdouble'),
('longcomplex', 'clongdouble'),
('bool_', 'bool'),
('unicode_', 'unicode'),
('object_', 'object')]
if sys.version_info[0] >= 3:
type_pairs.extend([('bytes_', 'string'),
('str_', 'unicode'),
('string_', 'string')])
else:
type_pairs.extend([('str_', 'string'),
('string_', 'string'),
('bytes_', 'string')])
for alias, t in type_pairs:
allTypes[alias] = allTypes[t]
sctypeDict[alias] = sctypeDict[t]
# Remove aliases overriding python types and modules
to_remove = ['ulong', 'object', 'unicode', 'int', 'long', 'float',
'complex', 'bool', 'string', 'datetime', 'timedelta']
if sys.version_info[0] >= 3:
# Py3K
to_remove.append('bytes')
to_remove.append('str')
to_remove.remove('unicode')
to_remove.remove('long')
for t in to_remove:
try:
del allTypes[t]
del sctypeDict[t]
except KeyError:
pass
def maximum_sctype(t):
"""
Return the scalar type of highest precision of the same kind as the input.
Parameters
----------
t : dtype or dtype specifier
The input data type. This can be a `dtype` object or an object that
is convertible to a `dtype`.
Returns
-------
out : dtype
The highest precision data type of the same kind (`dtype.kind`) as `t`.
See Also
--------
obj2sctype, mintypecode, sctype2char
dtype
Examples
--------
>>> np.maximum_sctype(np.int)
<type 'numpy.int64'>
>>> np.maximum_sctype(np.uint8)
<type 'numpy.uint64'>
>>> np.maximum_sctype(np.complex)
<type 'numpy.complex192'>
>>> np.maximum_sctype(str)
<type 'numpy.string_'>
>>> np.maximum_sctype('i2')
<type 'numpy.int64'>
>>> np.maximum_sctype('f4')
<type 'numpy.float96'>
"""
g = obj2sctype(t)
if g is None:
return t
t = g
name = t.__name__
base, bits = _evalname(name)
if bits == 0:
return t
else:
return sctypes[base][-1]
def sctype2char(sctype):
"""
Return the string representation of a scalar dtype.
Parameters
----------
sctype : scalar dtype or object
If a scalar dtype, the corresponding string character is
returned. If an object, `sctype2char` tries to infer its scalar type
and then return the corresponding string character.
Returns
-------
typechar : str
The string character corresponding to the scalar type.
Raises
------
ValueError
If `sctype` is an object for which the type can not be inferred.
See Also
--------
obj2sctype, issctype, issubsctype, mintypecode
Examples
--------
>>> for sctype in [np.int32, np.float, np.complex, np.string_, np.ndarray]:
... print(np.sctype2char(sctype))
l
d
D
S
O
>>> x = np.array([1., 2-1.j])
>>> np.sctype2char(x)
'D'
>>> np.sctype2char(list)
'O'
"""
sctype = obj2sctype(sctype)
if sctype is None:
raise ValueError("unrecognized type")
return _sctype2char_dict[sctype]
# Create dictionary of casting functions that wrap sequences
# indexed by type or type character
