def __new__(cls, label, range=None, **kw_args):
from diofant.utilities.misc import filldedent
if isinstance(label, str):
label = Symbol(label, integer=True)
label, range = list(map(sympify, (label, range)))
if not label.is_integer:
raise TypeError("Idx object requires an integer label.")
elif is_sequence(range):
if len(range) != 2:
raise ValueError(
filldedent("""
Idx range tuple must have length 2, but got %s""" %
len(range)))
for bound in range:
if not (bound.is_integer or abs(bound) is S.Infinity):
raise TypeError("Idx object requires integer bounds.")
args = label, Tuple(*range)
elif isinstance(range, Expr):
if not (range.is_integer or range is S.Infinity):
raise TypeError("Idx object requires an integer dimension.")
args = label, Tuple(0, range - 1)
elif range:
raise TypeError(
filldedent("""
The range must be an ordered iterable or
integer Diofant expression."""))
else:
args = label,
obj = Expr.__new__(cls, *args, **kw_args)
return obj
def _new(cls, poly, func, auto=True):
"""Construct new raw ``RootSum`` instance. """
obj = Expr.__new__(cls)
obj.poly = poly
obj.fun = func
obj.auto = auto
return obj
def __new__(cls, label, shape=None, **kw_args):
if isinstance(label, str):
label = Symbol(label)
elif isinstance(label, (Dummy, Symbol)):
pass
else:
raise TypeError("Base label should be a string or Symbol.")
obj = Expr.__new__(cls, label, **kw_args)
if is_sequence(shape):
obj._shape = Tuple(*shape)
else:
obj._shape = sympify(shape)
return obj
def __new__(cls, base, *args, **kw_args):
from diofant.utilities.misc import filldedent
if not args:
raise IndexException("Indexed needs at least one index.")
if isinstance(base, (str, Symbol)):
base = IndexedBase(base)
elif not hasattr(base, '__getitem__') and not isinstance(
base, IndexedBase):
raise TypeError(
filldedent("""
Indexed expects string, Symbol or IndexedBase as base."""))
args = list(map(sympify, args))
return Expr.__new__(cls, base, *args, **kw_args)
def _new(cls, poly, index):
"""Construct new ``RootOf`` object from raw data. """
obj = Expr.__new__(cls)
obj.poly = PurePoly(poly)
obj.index = index
try:
_reals_cache[obj.poly] = _reals_cache[poly]
_complexes_cache[obj.poly] = _complexes_cache[poly]
except KeyError:
pass
return obj
def __new__(cls, e, z, z0, dir="+"):
e = sympify(e)
z = sympify(z)
z0 = sympify(z0)
if z0 is S.Infinity:
dir = "-"
elif z0 is S.NegativeInfinity:
dir = "+"
if isinstance(dir, str):
dir = Symbol(dir)
elif not isinstance(dir, Symbol):
raise TypeError("direction must be of type str or Symbol, not %s" %
type(dir))
if str(dir) not in ('+', '-', 'real'):
raise ValueError(
"direction must be either '+' or '-' or 'real', not %s" % dir)
obj = Expr.__new__(cls)
obj._args = (e, z, z0, dir)
return obj
def __new__(cls, expr, *args, **kwargs):
expr = sympify(expr)
if not args:
if expr.is_Order:
variables = expr.variables
point = expr.point
else:
variables = list(expr.free_symbols)
point = [S.Zero]*len(variables)
else:
args = list(args if is_sequence(args) else [args])
variables, point = [], []
if is_sequence(args[0]):
for a in args:
v, p = list(map(sympify, a))
variables.append(v)
point.append(p)
else:
variables = list(map(sympify, args))
point = [S.Zero]*len(variables)
if not all(isinstance(v, (Dummy, Symbol)) for v in variables):
raise TypeError('Variables are not symbols, got %s' % variables)
if len(list(uniq(variables))) != len(variables):
raise ValueError('Variables are supposed to be unique symbols, got %s' % variables)
if expr.is_Order:
expr_vp = dict(expr.args[1:])
new_vp = dict(expr_vp)
vp = dict(zip(variables, point))
for v, p in vp.items():
if v in new_vp.keys():
if p != new_vp[v]:
raise NotImplementedError(
"Mixing Order at different points is not supported.")
else:
new_vp[v] = p
if set(expr_vp.keys()) == set(new_vp.keys()):
return expr
else:
variables = list(new_vp.keys())
point = [new_vp[v] for v in variables]
if expr is S.NaN:
return S.NaN
if any(x in p.free_symbols for x in variables for p in point):
raise ValueError('Got %s as a point.' % point)
if variables:
if any(p != point[0] for p in point):
raise NotImplementedError
if point[0] in [S.Infinity, S.NegativeInfinity]:
s = {k: 1/Dummy() for k in variables}
rs = {1/v: 1/k for k, v in s.items()}
elif point[0] is not S.Zero:
s = {k: Dummy() + point[0] for k in variables}
rs = {v - point[0]: k - point[0] for k, v in s.items()}
else:
s = ()
rs = ()
expr = expr.subs(s)
if expr.is_Add:
from diofant import expand_multinomial
expr = expand_multinomial(expr)
if s:
args = tuple(r[0] for r in rs.items())
else:
args = tuple(variables)
if len(variables) > 1:
# XXX: better way? We need this expand() to
# workaround e.g: expr = x*(x + y).
# (x*(x + y)).as_leading_term(x, y) currently returns
# x*y (wrong order term!). That's why we want to deal with
# expand()'ed expr (handled in "if expr.is_Add" branch below).
expr = expr.expand()
if expr.is_Add:
lst = expr.extract_leading_order(args)
expr = Add(*[f.expr for (e, f) in lst])
elif expr:
expr = expr.as_leading_term(*args)
expr = expr.as_independent(*args, as_Add=False)[1]
expr = expand_power_base(expr)
expr = expand_log(expr)
if len(args) == 1:
# The definition of O(f(x)) symbol explicitly stated that
# the argument of f(x) is irrelevant. That's why we can
# combine some power exponents (only "on top" of the
# expression tree for f(x)), e.g.:
# x**p * (-x)**q -> x**(p+q) for real p, q.
x = args[0]
margs = list(Mul.make_args(
expr.as_independent(x, as_Add=False)[1]))
for i, t in enumerate(margs):
if t.is_Pow:
b, q = t.args
if b in (x, -x) and q.is_extended_real and not q.has(x):
margs[i] = x**q
elif b.is_Pow and not b.exp.has(x):
b, r = b.args
if b in (x, -x) and r.is_extended_real:
margs[i] = x**(r*q)
elif b.is_Mul and b.args[0] is S.NegativeOne:
b = -b
if b.is_Pow and not b.exp.has(x):
b, r = b.args
if b in (x, -x) and r.is_extended_real:
margs[i] = x**(r*q)
expr = Mul(*margs)
expr = expr.subs(rs)
if expr is S.Zero:
return expr
if expr.is_Order:
expr = expr.expr
if not expr.has(*variables):
expr = S.One
# create Order instance:
vp = dict(zip(variables, point))
variables.sort(key=default_sort_key)
point = [vp[v] for v in variables]
args = (expr,) + Tuple(*zip(variables, point))
obj = Expr.__new__(cls, *args)
return obj