"""numerictypes: Define the numeric type objects
This module is designed so 'from numerictypes import *' is safe.
Exported symbols include:
Dictionary with all registered number types (including aliases):
typeDict
Type objects (not all will be available, depends on platform):
see variable sctypes for which ones you have
Bit-width names
int8 int16 int32 int64 int128
uint8 uint16 uint32 uint64 uint128
float16 float32 float64 float96 float128 float256
complex32 complex64 complex128 complex192 complex256 complex512
c-based names
bool_
object_
void, str_, unicode_
byte, ubyte,
short, ushort
intc, uintc,
intp, uintp,
int_, uint,
longlong, ulonglong,
single, csingle,
float_, complex_,
longfloat, clongfloat,
As part of the type-hierarchy: xx -- is bit-width
generic
+-> bool_ (kind=b)
+-> number (kind=i)
| integer
| signedinteger (intxx)
| byte
| short
| intc
| intp int0
| int_
| longlong
+-> unsignedinteger (uintxx) (kind=u)
| ubyte
| ushort
| uintc
| uintp uint0
| uint_
| ulonglong
+-> inexact
| +-> floating (floatxx) (kind=f)
| | single
| | float_ (double)
| | longfloat
| \-> complexfloating (complexxx) (kind=c)
| csingle (singlecomplex)
| complex_ (cfloat, cdouble)
| clongfloat (longcomplex)
+-> flexible
| character
| str_ (string_) (kind=S)
| unicode_ (kind=U)
| void (kind=V)
|
\-> object_ (not used much) (kind=O)
"""
# we add more at the bottom
__all__ = ['sctypeDict', 'sctypeNA', 'typeDict', 'typeNA', 'sctypes',
'ScalarType', 'obj2sctype', 'cast', 'nbytes', 'sctype2char',
'maximum_sctype', 'issctype', 'typecodes', 'find_common_type']
from numpy.core.multiarray import typeinfo,ndarray,array,empty,dtype
import types as _types
# we don't export these for import *, but we do want them accessible
# as numerictypes.bool, etc.
from __builtin__ import bool,int,long,float,complex,object,unicode,str
# String-handling utilities to avoid locale-dependence.
import string
LOWER_TABLE = string.maketrans(string.ascii_uppercase, string.ascii_lowercase)
UPPER_TABLE = string.maketrans(string.ascii_lowercase, string.ascii_uppercase)
def english_lower(s):
""" Apply English case rules to convert ASCII strings to all lower case.
This is an internal utility function to replace calls to str.lower() such
that we can avoid changing behavior with changing locales. In particular,
Turkish has distinct dotted and dotless variants of the Latin letter "I" in
both lowercase and uppercase. Thus, "I".lower() != "i" in a "tr" locale.
Parameters
----------
s : str
Returns
-------
lowered : str
Examples
--------
>>> from numpy.lib.utils import english_lower
>>> english_lower('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_')
'abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789_'
>>> english_upper('')
''
"""
lowered = s.translate(LOWER_TABLE)
return lowered
def english_upper(s):
""" Apply English case rules to convert ASCII strings to all upper case.
This is an internal utility function to replace calls to str.upper() such
that we can avoid changing behavior with changing locales. In particular,
Turkish has distinct dotted and dotless variants of the Latin letter "I" in
both lowercase and uppercase. Thus, "i".upper() != "I" in a "tr" locale.
Parameters
----------
s : str
Returns
-------
uppered : str
Examples
--------
>>> from numpy.lib.utils import english_upper
>>> english_upper('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_')
'ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_'
>>> english_upper('')
''
"""
uppered = s.translate(UPPER_TABLE)
return uppered
def english_capitalize(s):
""" Apply English case rules to convert the first character of an ASCII
string to upper case.
This is an internal utility function to replace calls to str.capitalize()
such that we can avoid changing behavior with changing locales.
Parameters
----------
s : str
Returns
-------
capitalized : str
Examples
--------
>>> from numpy.lib.utils import english_capitalize
>>> english_capitalize('int8')
'Int8'
>>> english_capitalize('Int8')
'Int8'
>>> english_capitalize('')
''
"""
if s:
return english_upper(s[0]) + s[1:]
else:
return s
sctypeDict = {} # Contains all leaf-node scalar types with aliases
sctypeNA = {} # Contails all leaf-node types -> numarray type equivalences
allTypes = {} # Collect the types we will add to the module here
def _evalname(name):
k = 0
for ch in name:
if ch in '0123456789':
break
k += 1
try:
bits = int(name[k:])
except ValueError:
bits = 0
base = name[:k]
return base, bits
def bitname(obj):
"""Return a bit-width name for a given type object"""
name = obj.__name__
base = ''
char = ''
try:
if name[-1] == '_':
newname = name[:-1]
else:
newname = name
info = typeinfo[english_upper(newname)]
assert(info[-1] == obj) # sanity check
bits = info[2]
except KeyError: # bit-width name
base, bits = _evalname(name)
char = base[0]
if name == 'bool_':
char = 'b'
base = 'bool'
elif name=='string_':
char = 'S'
base = 'string'
elif name=='unicode_':
char = 'U'
base = 'unicode'
elif name=='void':
char = 'V'
base = 'void'
elif name=='object_':
char = 'O'
base = 'object'
bits = 0
bytes = bits / 8
if char != '' and bytes != 0:
char = "%s%d" % (char, bytes)
return base, bits, char
def _add_types():
for a in typeinfo.keys():
name = english_lower(a)
if isinstance(typeinfo[a], tuple):
typeobj = typeinfo[a][-1]
# define C-name and insert typenum and typechar references also
allTypes[name] = typeobj
sctypeDict[name] = typeobj
sctypeDict[typeinfo[a][0]] = typeobj
sctypeDict[typeinfo[a][1]] = typeobj
else: # generic class
allTypes[name] = typeinfo[a]
_add_types()
def _add_aliases():
for a in typeinfo.keys():
name = english_lower(a)
if not isinstance(typeinfo[a], tuple):
continue
typeobj = typeinfo[a][-1]
# insert bit-width version for this class (if relevant)
base, bit, char = bitname(typeobj)
if base[-3:] == 'int' or char[0] in 'ui': continue
if base != '':
myname = "%s%d" % (base, bit)
if (name != 'longdouble' and name != 'clongdouble') or \
myname not in allTypes.keys():
allTypes[myname] = typeobj
sctypeDict[myname] = typeobj
if base == 'complex':
na_name = '%s%d' % (english_capitalize(base), bit/2)
elif base == 'bool':
na_name = english_capitalize(base)
sctypeDict[na_name] = typeobj
else:
na_name = "%s%d" % (english_capitalize(base), bit)
sctypeDict[na_name] = typeobj
sctypeNA[na_name] = typeobj
sctypeDict[na_name] = typeobj
sctypeNA[typeobj] = na_name
sctypeNA[typeinfo[a][0]] = na_name
if char != '':
sctypeDict[char] = typeobj
sctypeNA[char] = na_name
_add_aliases()
# Integers handled so that
# The int32, int64 types should agree exactly with
# PyArray_INT32, PyArray_INT64 in C
# We need to enforce the same checking as is done
# in arrayobject.h where the order of getting a
# bit-width match is:
# long, longlong, int, short, char
# for int8, int16, int32, int64, int128
def _add_integer_aliases():
_ctypes = ['LONG', 'LONGLONG', 'INT', 'SHORT', 'BYTE']
for ctype in _ctypes:
val = typeinfo[ctype]
bits = val[2]
charname = 'i%d' % (bits/8,)
ucharname = 'u%d' % (bits/8,)
intname = 'int%d' % bits
UIntname = 'UInt%d' % bits
Intname = 'Int%d' % bits
uval = typeinfo['U'+ctype]
typeobj = val[-1]
utypeobj = uval[-1]
if intname not in allTypes.keys():
uintname = 'uint%d' % bits
allTypes[intname] = typeobj
allTypes[uintname] = utypeobj
sctypeDict[intname] = typeobj
sctypeDict[uintname] = utypeobj
sctypeDict[Intname] = typeobj
sctypeDict[UIntname] = utypeobj
sctypeDict[charname] = typeobj
sctypeDict[ucharname] = utypeobj
sctypeNA[Intname] = typeobj
sctypeNA[UIntname] = utypeobj
sctypeNA[charname] = typeobj
sctypeNA[ucharname] = utypeobj
sctypeNA[typeobj] = Intname
sctypeNA[utypeobj] = UIntname
sctypeNA[val[0]] = Intname
sctypeNA[uval[0]] = UIntname
_add_integer_aliases()
# We use these later
void = allTypes['void']
generic = allTypes['generic']
#
# Rework the Python names (so that float and complex and int are consistent
# with Python usage)
#
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'),
('str_', 'string'),
('string_', 'string'),
('object_', 'object')]
for alias, t in type_pairs:
allTypes[alias] = allTypes[t]
sctypeDict[alias] = sctypeDict[t]
# Remove aliases overriding python types and modules
for t in ['ulong', 'object', 'unicode', 'int', 'long', 'float',
'complex', 'bool', 'string']:
try:
del allTypes[t]
del sctypeDict[t]
except KeyError:
pass
_set_up_aliases()
# Now, construct dictionary to lookup character codes from types
_sctype2char_dict = {}
def _construct_char_code_lookup():
for name in typeinfo.keys():
tup = typeinfo[name]
if isinstance(tup, tuple):
if tup[0] not in ['p','P']:
_sctype2char_dict[tup[-1]] = tup[0]
_construct_char_code_lookup()
sctypes = {'int': [],
'uint':[],
'float':[],
'complex':[],
'others':[bool,object,str,unicode,void]}
def _add_array_type(typename, bits):
try:
t = allTypes['%s%d' % (typename, bits)]
except KeyError:
pass
else:
sctypes[typename].append(t)
def _set_array_types():
ibytes = [1, 2, 4, 8, 16, 32, 64]
fbytes = [2, 4, 8, 10, 12, 16, 32, 64]
for bytes in ibytes:
bits = 8*bytes
_add_array_type('int', bits)
_add_array_type('uint', bits)
for bytes in fbytes:
bits = 8*bytes
_add_array_type('float', bits)
_add_array_type('complex', 2*bits)
_gi = dtype('p')
if _gi.type not in sctypes['int']:
indx = 0
sz = _gi.itemsize
_lst = sctypes['int']
while (indx < len(_lst) and sz >= _lst[indx](0).itemsize):
indx += 1
sctypes['int'].insert(indx, _gi.type)
sctypes['uint'].insert(indx, dtype('P').type)
_set_array_types()
genericTypeRank = ['bool', 'int8', 'uint8', 'int16', 'uint16',
'int32', 'uint32', 'int64', 'uint64', 'int128',
'uint128', 'float16',
'float32', 'float64', 'float80', 'float96', 'float128',
'float256',
'complex32', 'complex64', 'complex128', 'complex160',
'complex192', 'complex256', 'complex512', 'object']
def maximum_sctype(t):
"""returns the sctype of highest precision of the same general kind as 't'"""
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_types = {int : 'int_',
float: 'float_',
complex: 'complex_',
bool: 'bool_',
str: 'string_',
unicode: 'unicode_',
_types.BufferType: 'void',
}
def _python_type(t):
"""returns the type corresponding to a certain Python type"""
if not isinstance(t, _types.TypeType):
t = type(t)
return allTypes[_python_types.get(t, 'object_')]
def issctype(rep):
"""Determines whether the given object represents
a numeric array type."""
if not isinstance(rep, (type, dtype)):
return False
try:
res = obj2sctype(rep)
if res and res != object_:
return True
return False
except:
return False
def obj2sctype(rep, default=None):
try:
if issubclass(rep, generic):
return rep
except TypeError:
pass
if isinstance(rep, dtype):
return rep.type
if isinstance(rep, type):
return _python_type(rep)
if isinstance(rep, ndarray):
return rep.dtype.type
try:
res = dtype(rep)
except:
return default
return res.type
# This dictionary allows look up based on any alias for an array data-type
class _typedict(dict):
def __getitem__(self, obj):
return dict.__getitem__(self, obj2sctype(obj))
nbytes = _typedict()
_alignment = _typedict()
_maxvals = _typedict()
_minvals = _typedict()
def _construct_lookups():
for name, val in typeinfo.iteritems():
if not isinstance(val, tuple):
continue
obj = val[-1]
nbytes[obj] = val[2] / 8
_alignment[obj] = val[3]
if (len(val) > 5):
_maxvals[obj] = val[4]
_minvals[obj] = val[5]
else:
_maxvals[obj] = None
_minvals[obj] = None
_construct_lookups()
def sctype2char(sctype):
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
cast = _typedict()
ScalarType = [_types.IntType, _types.FloatType,
_types.ComplexType, _types.LongType, _types.BooleanType,
_types.StringType, _types.UnicodeType, _types.BufferType]
ScalarType.extend(_sctype2char_dict.keys())
ScalarType = tuple(ScalarType)
for key in _sctype2char_dict.keys():
cast[key] = lambda x, k=key : array(x, copy=False).astype(k)
_unicodesize = array('u','U1').itemsize
# Create the typestring lookup dictionary
_typestr = _typedict()
for key in _sctype2char_dict.keys():
if issubclass(key, allTypes['flexible']):
_typestr[key] = _sctype2char_dict[key]
else:
_typestr[key] = empty((1,),key).dtype.str[1:]
# Make sure all typestrings are in sctypeDict
for key, val in _typestr.items():
if val not in sctypeDict:
sctypeDict[val] = key
# Add additional strings to the sctypeDict
_toadd = ['int', 'float', 'complex', 'bool', 'object', 'string', ('str', allTypes['string_']),
'unicode', 'object', ('a', allTypes['string_'])]
for name in _toadd:
if isinstance(name, tuple):
sctypeDict[name[0]] = name[1]
else:
sctypeDict[name] = allTypes['%s_' % name]
del _toadd, name
# Now add the types we've determined to this module
for key in allTypes:
globals()[key] = allTypes[key]
__all__.append(key)
del key
typecodes = {'Character':'c',
'Integer':'bhilqp',
'UnsignedInteger':'BHILQP',
'Float':'fdg',
'Complex':'FDG',
'AllInteger':'bBhHiIlLqQpP',
'AllFloat':'fdgFDG',
'All':'?bhilqpBHILQPfdgFDGSUVO'}
# backwards compatibility --- deprecated name
typeDict = sctypeDict
typeNA = sctypeNA
# b -> boolean
# u -> unsigned integer
# i -> signed integer
# f -> floating point
# c -> complex
# S -> string
# U -> Unicode string
# V -> record
# O -> Python object
_kind_list = ['b', 'u', 'i', 'f', 'c', 'S', 'U', 'V', 'O']
__test_types = typecodes['AllInteger'][:-2]+typecodes['AllFloat']+'O'
__len_test_types = len(__test_types)
# Keep incrementing until a common type both can be coerced to
# is found. Otherwise, return None
def _find_common_coerce(a, b):
if a > b:
return a
try:
thisind = __test_types.index(a.char)
except ValueError:
return None
while thisind < __len_test_types:
newdtype = dtype(__test_types[thisind])
if newdtype >= b and newdtype >= a:
return newdtype
thisind += 1
return None
def find_common_type(array_types, scalar_types):
"""Determine common type following standard coercion rules
Parameters
----------
array_types : sequence
A list of dtype convertible objects representing arrays
scalar_types : sequence
A list of dtype convertible objects representing scalars
Returns
-------
datatype : dtype
The common data-type which is the maximum of the array_types
ignoring the scalar_types unless the maximum of the scalar_types
is of a different kind.
If the kinds is not understood, then None is returned.
"""
array_types = [dtype(x) for x in array_types]
scalar_types = [dtype(x) for x in scalar_types]
if len(scalar_types) == 0:
if len(array_types) == 0:
return None
else:
return max(array_types)
if len(array_types) == 0:
return max(scalar_types)
maxa = max(array_types)
maxsc = max(scalar_types)
try:
index_a = _kind_list.index(maxa.kind)
index_sc = _kind_list.index(maxsc.kind)
except ValueError:
return None
if index_sc > index_a:
return _find_common_coerce(maxsc,maxa)
else:
return maxa
|