Beispiel #1
0
    def __new__(cls, label, shape=None, **kw_args):
        from sympy import MatrixBase, NDimArray

        if isinstance(label, string_types):
            label = Symbol(label)
        elif isinstance(label, Symbol):
            pass
        elif isinstance(label, (MatrixBase, NDimArray)):
            return label
        elif isinstance(label, Iterable):
            return _sympify(label)
        else:
            label = _sympify(label)

        if is_sequence(shape):
            shape = Tuple(*shape)
        elif shape is not None:
            shape = Tuple(shape)

        offset = kw_args.pop('offset', S.Zero)
        strides = kw_args.pop('strides', None)

        if shape is not None:
            obj = Expr.__new__(cls, label, shape)
        else:
            obj = Expr.__new__(cls, label)
        obj._shape = shape
        obj._offset = offset
        obj._strides = strides
        obj._name = str(label)
        return obj
Beispiel #2
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 def __new__(cls, base, *args, **kw_args):
     if not args: raise IndexException("Indexed needs at least one index")
     if isinstance(base, (basestring, Symbol)):
         base = IndexedBase(base)
     elif not isinstance(base, IndexedBase):
         raise TypeError("Indexed expects string, Symbol or IndexedBase as base")
     return Expr.__new__(cls, base, *args, **kw_args)
Beispiel #3
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 def __new__(cls, name, abbrev, **assumptions):
     obj = Expr.__new__(cls, **assumptions)
     assert isinstance(name, str),`type(name)`
     assert isinstance(abbrev, str),`type(abbrev)`
     obj.name = name
     obj.abbrev = abbrev
     return obj
Beispiel #4
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 def __new__(cls, e, z, z0, dir="+"):
     e = sympify(e)
     z = sympify(z)
     z0 = sympify(z0)
     obj = Expr.__new__(cls)
     obj._args = (e, z, z0, dir)
     return obj
Beispiel #5
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    def __new__(cls, function, *symbols, **assumptions):
        # Any embedded piecewise functions need to be brought out to the
        # top level so that integration can go into piecewise mode at the
        # earliest possible moment.
        function = piecewise_fold(sympify(function))

        if function.is_Number:
            if function is S.NaN:
                return S.NaN
            elif function is S.Infinity:
                return S.Infinity
            elif function is S.NegativeInfinity:
                return S.NegativeInfinity

        if symbols:
            limits = []

            for V in symbols:
                if isinstance(V, Symbol):
                    limits.append(Tuple(V))
                    continue
                elif isinstance(V, (tuple, list, Tuple)):
                    V = flatten(V)
                    newsymbol = sympify(V[0])
                    if len(V) == 3:
                        if isinstance(newsymbol, Symbol):
                            nlim = map(sympify, V[1:])
                            if V[1] is None and V[2] is not None:
                                nlim = [V[2]]
                            if V[2] is None and V[1] is not None:
                                function = -function
                                nlim = [V[1]]
                            if V[1] is None and V[2] is None:
                                nlim = []
                            limits.append( Tuple(newsymbol, *nlim ))
                            continue
                    elif len(V) == 1 or (len(V) == 2 and V[1] is None):
                        if isinstance(newsymbol, Symbol):
                            limits.append(Tuple(newsymbol))
                            continue
                    elif len(V) == 2:
                        if isinstance(newsymbol, Symbol):
                            limits.append(Tuple(newsymbol,V[1]))
                            continue


                raise ValueError("Invalid integration variable or limits: %s" % str(symbols))
        else:
            # no symbols provided -- let's compute full anti-derivative
            limits = [Tuple(symb) for symb in function.atoms(Symbol)]

            if not limits:
                return function

        obj = Expr.__new__(cls, **assumptions)
        arglist = [function]
        arglist.extend(limits)
        obj._args = tuple(arglist)

        return obj
Beispiel #6
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    def __new__(cls, function, *symbols, **assumptions):
        from sympy.integrals.integrals import _process_limits

        # Any embedded piecewise functions need to be brought out to the
        # top level so that integration can go into piecewise mode at the
        # earliest possible moment.
        function = piecewise_fold(sympify(function))

        if function is S.NaN:
            return S.NaN

        if not symbols:
            raise ValueError("Summation variables must be given")

        limits, sign = _process_limits(*symbols)

        # Only limits with lower and upper bounds are supported; the indefinite Sum
        # is not supported
        if any(len(l) != 3 or None in l for l in limits):
            raise ValueError('Sum requires values for lower and upper bounds.')

        obj = Expr.__new__(cls, **assumptions)
        arglist = [sign*function]
        arglist.extend(limits)
        obj._args = tuple(arglist)

        return obj
Beispiel #7
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    def __new__(cls, label, range=None, **kw_args):
        from sympy.utilities.misc import filldedent

        if isinstance(label, basestring):
            label = Symbol(label, integer=True)
        label, range = 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 SymPy expression."""))
        else:
            args = label,

        obj = Expr.__new__(cls, *args, **kw_args)
        return obj
Beispiel #8
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    def __new__(cls, function, *symbols, **assumptions):

        # Any embedded piecewise functions need to be brought out to the
        # top level so that integration can go into piecewise mode at the
        # earliest possible moment.
        function = piecewise_fold(sympify(function))

        if function is S.NaN:
            return S.NaN

        if symbols:
            limits, sign = _process_limits(*symbols)
        else:
            # no symbols provided -- let's compute full anti-derivative
            limits, sign = [Tuple(s) for s in function.free_symbols], 1

            if len(limits) != 1:
                raise ValueError("specify integration variables to integrate %s" % function)

        while isinstance(function, Integral):
            # denest the integrand
            limits = list(function.limits) + limits
            function = function.function

        obj = Expr.__new__(cls, **assumptions)
        arglist = [sign*function]
        arglist.extend(limits)
        obj._args = tuple(arglist)
        obj.is_commutative = all(s.is_commutative for s in obj.free_symbols)

        return obj
Beispiel #9
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    def __new__(cls, term, *symbols, **assumptions):
        term = sympify(term)

        if term is S.NaN:
            return S.NaN

        if len(symbols) == 1:
            symbol = symbols[0]

            if isinstance(symbol, C.Equality):
                k = symbol.lhs
                a = symbol.rhs.start
                n = symbol.rhs.end
            elif is_sequence(symbol):
                k, a, n = symbol
            else:
                raise ValueError("Invalid arguments")

            k, a, n = map(sympify, (k, a, n))

        else:
            raise NotImplementedError

        obj = Expr.__new__(cls, **assumptions)
        obj._args = (term, Tuple(k, a, n))

        return obj
Beispiel #10
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    def __new__(cls, label, range=None, **kw_args):

        if isinstance(label, basestring):
            label = Symbol(label, integer=True)
        label, range = map(sympify, (label, range))

        if not label.is_integer:
            raise TypeError("Idx object requires an integer label")

        elif is_sequence(range):
            assert len(range) == 2, "Idx got range tuple with wrong length"
            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(S.Zero, range-S.One)
        elif range:
            raise TypeError("range must be ordered iterable or integer sympy expression")
        else:
            args = label,

        obj = Expr.__new__(cls, *args, **kw_args)
        return obj
Beispiel #11
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 def __new__(cls, arg):
     if hasattr(arg, 'adjoint'):
         obj = arg.adjoint()
     elif hasattr(arg, 'conjugate') and hasattr(arg, 'transpose'):
         obj = arg.conjugate().transpose()
     if obj is not None:
         return obj
     return Expr.__new__(cls, arg)
Beispiel #12
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 def __new__(cls, arg):
     if hasattr(arg, "adjoint"):
         obj = arg.adjoint()
     elif hasattr(arg, "conjugate") and hasattr(arg, "transpose"):
         obj = arg.conjugate().transpose()
     if obj is not None:
         return obj
     return Expr.__new__(cls, arg)
Beispiel #13
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    def _new(cls, poly, index):
        """Construct new ``RootOf`` object from raw data. """
        obj = Expr.__new__(cls)

        obj.poly = poly
        obj.index = index

        return obj
Beispiel #14
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    def __new__(cls, label, shape=None, **kw_args):
        if isinstance(label, string_types):
            label = Symbol(label)
        elif isinstance(label, Symbol):
            pass
        else:
            raise TypeError("Base label should be a string or Symbol.")

        if is_sequence(shape):
            shape = Tuple(*shape)
        else:
            shape = sympify(shape)
        if shape is not None:
            obj = Expr.__new__(cls, label, shape, **kw_args)
        else:
            obj = Expr.__new__(cls, label, **kw_args)
        obj._shape = shape
        return obj
Beispiel #15
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 def __new__(cls, name, n, m):
     n, m = map(sympify, (n, m))
     from sympy import MatrixBase
     if isinstance(name, (MatrixBase,)):
         if n.is_Integer and m.is_Integer:
             return name[n, m]
     name = sympify(name)
     obj = Expr.__new__(cls, name, n, m)
     return obj
Beispiel #16
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    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
Beispiel #17
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    def __new__(cls, label, shape=None, **kw_args):
        if isinstance(label, basestring):
            label = Symbol(label)

        obj = Expr.__new__(cls, label, **kw_args)
        if is_sequence(shape):
            obj._shape = Tuple(*shape)
        else:
            obj._shape = shape
        return obj
Beispiel #18
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    def __new__(cls, f, x=None):
        if not isinstance(f, Poly):
            f = Poly(f, x)
        elif x is not None:
            raise SymbolsError("Redundant symbols were given")

        if f.is_multivariate:
            raise ValueError('multivariate polynomial')

        return Expr.__new__(cls, f)
Beispiel #19
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 def __new__(cls, base, *args, **kw_args):
     if not args: raise IndexException("Indexed needs at least one index")
     if isinstance(base, (basestring, Symbol)):
         base = IndexedBase(base)
     elif not isinstance(base, IndexedBase):
         raise TypeError("Indexed expects string, Symbol or IndexedBase as base")
     # FIXME: 2.4 compatibility
     args = map(_ensure_Idx, args)
     # args = tuple([ a if isinstance(a, Idx) else Idx(a) for a in args ])
     return Expr.__new__(cls, base, *args, **kw_args)
Beispiel #20
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    def __new__(cls, label, shape=None, **kw_args):
        if isinstance(label, string_types):
            label = Symbol(label)
        elif isinstance(label, Symbol):
            pass
        else:
            label = _sympify(label)

        if is_sequence(shape):
            shape = Tuple(*shape)
        elif shape is not None:
            shape = Tuple(shape)

        if shape is not None:
            obj = Expr.__new__(cls, label, shape, **kw_args)
        else:
            obj = Expr.__new__(cls, label, **kw_args)
        obj._shape = shape
        return obj
Beispiel #21
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    def __new__(cls, function, *symbols, **assumptions):
        # Any embedded piecewise functions need to be brought out to the
        # top level so that integration can go into piecewise mode at the
        # earliest possible moment.
        function = piecewise_fold(sympify(function))

        if function is S.NaN:
            return S.NaN

        symbols = list(symbols)
        if not symbols:
            # no symbols provided -- let's compute full anti-derivative
            symbols = sorted(function.free_symbols, Basic.compare)
            if not symbols:
                raise ValueError('An integration variable is required.')

        while isinstance(function, Integral):
            # denest the integrand
            symbols = list(function.limits) + symbols
            function = function.function

        limits = []
        for V in symbols:
            if isinstance(V, Symbol):
                limits.append(Tuple(V))
                continue
            elif isinstance(V, (tuple, list, Tuple)):
                V = sympify(flatten(V))
                if V[0].is_Symbol:
                    newsymbol = V[0]
                    if len(V) == 3:
                        if V[1] is None and V[2] is not None:
                            nlim = [V[2]]
                        elif V[1] is not None and V[2] is None:
                            function = -function
                            nlim = [V[1]]
                        elif V[1] is None and V[2] is None:
                            nlim = []
                        else:
                            nlim = V[1:]
                        limits.append(Tuple(newsymbol, *nlim ))
                        continue
                    elif len(V) == 1 or (len(V) == 2 and V[1] is None):
                        limits.append(Tuple(newsymbol))
                        continue
                    elif len(V) == 2:
                        limits.append(Tuple(newsymbol, V[1]))
                        continue
            raise ValueError("Invalid integration variable or limits: %s" % str(symbols))

        obj = Expr.__new__(cls, **assumptions)
        obj._args = tuple([function] + limits)
        obj.is_commutative = all(s.is_commutative for s in obj.free_symbols)

        return obj
Beispiel #22
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 def __new__(cls, name, n, m):
     n, m = map(_sympify, (n, m))
     from sympy import MatrixBase
     if isinstance(name, (MatrixBase,)):
         if n.is_Integer and m.is_Integer:
             return name[n, m]
     if isinstance(name, string_types):
         name = Symbol(name)
     name = _sympify(name)
     obj = Expr.__new__(cls, name, n, m)
     return obj
Beispiel #23
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    def __new__(cls, base, *args, **kw_args):
        from sympy.utilities.misc import filldedent

        if not args:
            raise IndexException("Indexed needs at least one index.")
        if isinstance(base, (basestring, Symbol)):
            base = IndexedBase(base)
        elif not isinstance(base, IndexedBase):
            raise TypeError(filldedent("""
                Indexed expects string, Symbol or IndexedBase as base."""))
        return Expr.__new__(cls, base, *args, **kw_args)
Beispiel #24
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    def __new__(cls, label, shape=None, **kw_args):
        if not isinstance(label, (basestring, Symbol)):
            raise TypeError("Base label should be a string or Symbol.")

        label = sympify(label)
        obj = Expr.__new__(cls, label, **kw_args)
        if is_sequence(shape):
            obj._shape = Tuple(*shape)
        else:
            obj._shape = sympify(shape)
        return obj
Beispiel #25
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    def __new__(cls, f, *args, **flags):
        if not hasattr(f, '__call__'):
            raise TypeError("%s is not a callable object" % f)

        roots = RootsOf(*args)

        if not flags.get('evaluate', True):
            return Expr.__new__(cls, f, roots)
        else:
            if roots.count == 0:
                return S.Zero
            else:
                result = []

                for root in roots.exact_roots():
                    result.append(f(root))

                if len(result) < roots.count:
                    result.append(Expr.__new__(cls, f, roots))

                return Add(*result)
Beispiel #26
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    def __new__(cls, base, *args, **kw_args):
        from sympy.utilities.misc import filldedent

        if not args:
            raise IndexException("Indexed needs at least one index.")
        if isinstance(base, (string_types, 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)
Beispiel #27
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 def __new__(cls, e, z, z0, dir="+"):
     e = sympify(e)
     z = sympify(z)
     z0 = sympify(z0)
     if isinstance(dir, basestring):
         dir = Symbol(dir)
     elif not isinstance(dir, Symbol):
         raise TypeError("direction must be of type basestring or Symbol, not %s" % type(dir))
     if str(dir) not in ("+", "-"):
         raise ValueError("direction must be either '+' or '-', not %s" % dir)
     obj = Expr.__new__(cls)
     obj._args = (e, z, z0, dir)
     return obj
Beispiel #28
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    def __new__(cls, expr, *symbols, **assumptions):

        expr = sympify(expr).expand()
        if expr is S.NaN:
            return S.NaN

        if symbols:
            symbols = map(sympify, symbols)
            if not all(isinstance(s, Symbol) for s in symbols):
                raise NotImplementedError(
                    'Order at points other than 0 not supported.')
        else:
            symbols = list(expr.free_symbols)

        if expr.is_Order:

            new_symbols = list(expr.variables)
            for s in symbols:
                if s not in new_symbols:
                    new_symbols.append(s)
            if len(new_symbols) == len(expr.variables):
                return expr
            symbols = new_symbols

        elif symbols:

            if expr.is_Add:
                lst = expr.extract_leading_order(*symbols)
                expr = Add(*[f.expr for (e, f) in lst])
            elif expr:
                if len(symbols) > 1 or expr.is_commutative is False:
                    # TODO
                    # We cannot use compute_leading_term because that only
                    # works in one symbol.
                    expr = expr.as_leading_term(*symbols)
                else:
                    expr = expr.compute_leading_term(symbols[0])
                terms = expr.as_coeff_mul(*symbols)[1]
                s = set(symbols)
                expr = Mul(*[t for t in terms if s & t.free_symbols])

        if expr is S.Zero:
            return expr
        elif not expr.has(*symbols):
            expr = S.One

        # create Order instance:
        symbols.sort(key=cmp_to_key(Basic.compare))
        obj = Expr.__new__(cls, expr, *symbols, **assumptions)

        return obj
Beispiel #29
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    def _new(cls, poly, index):
        """Construct new ``CRootOf`` 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
Beispiel #30
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    def __new__(cls, function, argument, **kwargs):
        evaluate = kwargs.pop('evaluate', global_evaluate[0])
        argument = repack_if_can(sympify(unpack_if_can(argument)))

        if not is_Function(function):
            raise TypeError('function is not a FunctionClass, Functor or Lambda: %s'%function)

        if evaluate:
            function, argument = Apply.reduce(function, argument)

        if function == Id:
            return argument
        else:
            return Expr.__new__(cls, function, argument, **kwargs)
Beispiel #31
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    def __new__(cls, expr, *symbols, **assumptions):

        expr = sympify(expr)
        if expr is S.NaN:
            return S.NaN

        if symbols:
            symbols = map(sympify, symbols)
            if not all(isinstance(s, Symbol) for s in symbols):
                raise NotImplementedError(
                    'Order at points other than 0 not supported.')
        else:
            symbols = list(expr.free_symbols)

        if expr.is_Order:
            v = set(expr.variables)
            symbols = v | set(symbols)
            if symbols == v:
                return expr
            symbols = list(symbols)

        elif symbols:

            symbols = list(set(symbols))

            if len(symbols) > 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(*symbols)
                expr = Add(*[f.expr for (e, f) in lst])

            elif expr:
                expr = expr.as_leading_term(*symbols)
                expr = expr.as_independent(*symbols, as_Add=False)[1]

                expr = expand_power_base(expr)
                expr = expand_log(expr)

                if len(symbols) == 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 = symbols[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_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_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_real:
                                        margs[i] = x**(r * q)

                    expr = Mul(*margs)

        if expr is S.Zero:
            return expr

        if not expr.has(*symbols):
            expr = S.One

        # create Order instance:
        symbols.sort(key=cmp_to_key(Basic.compare))
        obj = Expr.__new__(cls, expr, *symbols, **assumptions)

        return obj
Beispiel #32
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    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(v.is_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(
                    "Multivariable orders at different points are not supported."
                )
            if point[0] is S.Infinity:
                s = {k: 1 / Dummy() for k in variables}
                rs = {1 / v: 1 / k for k, v in s.items()}
                ps = [S.Zero for p in point]
            elif point[0] is S.NegativeInfinity:
                s = {k: -1 / Dummy() for k in variables}
                rs = {-1 / v: -1 / k for k, v in s.items()}
                ps = [S.Zero for p in point]
            elif point[0] is not S.Zero:
                s = {k: Dummy() + point[0] for k in variables}
                rs = {(v - point[0]).together(): k - point[0]
                      for k, v in s.items()}
                ps = [S.Zero for p in point]
            else:
                s = ()
                rs = ()
                ps = list(point)

            expr = expr.subs(s)

            if expr.is_Add:
                expr = expr.factor()

            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()

            old_expr = None
            while old_expr != expr:
                old_expr = expr
                if expr.is_Add:
                    lst = expr.extract_leading_order(args)
                    expr = Add(*[f.expr for (e, f) in lst])

                elif expr:
                    try:
                        expr = expr.as_leading_term(*args)
                    except PoleError:
                        if isinstance(expr, Function) or\
                                all(isinstance(arg, Function) for arg in expr.args):
                            # It is not possible to simplify an expression
                            # containing only functions (which raise error on
                            # call to leading term) further
                            pass
                        else:
                            orders = []
                            pts = tuple(zip(args, ps))
                            for arg in expr.args:
                                try:
                                    lt = arg.as_leading_term(*args)
                                except PoleError:
                                    lt = arg
                                if lt not in args:
                                    order = Order(lt)
                                else:
                                    order = Order(lt, *pts)
                                orders.append(order)
                            if expr.is_Add:
                                new_expr = Order(Add(*orders), *pts)
                                if new_expr.is_Add:
                                    new_expr = Order(
                                        Add(*[a.expr for a in new_expr.args]),
                                        *pts)
                                expr = new_expr.expr
                            elif expr.is_Mul:
                                expr = Mul(*[a.expr for a in orders])
                            elif expr.is_Pow:
                                expr = orders[0].expr**orders[1].expr
                    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_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_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_real:
                                            margs[i] = x**(r * q)

                        expr = Mul(*margs)

            expr = expr.subs(rs)

        if expr.is_Order:
            expr = expr.expr

        if not expr.has(*variables) and not expr.is_zero:
            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
Beispiel #33
0
    def __new__(cls, function, *symbols, **assumptions):
        """Create an unevaluated integral.

        Arguments are an integrand followed by one or more limits.

        If no limits are given and there is only one free symbol in the
        expression, that symbol will be used, otherwise an error will be
        raised.

        >>> from sympy import Integral
        >>> from sympy.abc import x, y
        >>> Integral(x)
        Integral(x, x)
        >>> Integral(y)
        Integral(y, y)

        When limits are provided, they are interpreted as follows (using
        ``x`` as though it were the variable of integration):

            (x,) or x - indefinite integral
            (x, a) - "evaluate at" integral
            (x, a, b) - definite integral

        Although the same integral will be obtained from an indefinite
        integral and an "evaluate at" integral when ``a == x``, they
        respond differently to substitution:

        >>> i = Integral(x, x)
        >>> at = Integral(x, (x, x))
        >>> i.doit() == at.doit()
        True
        >>> i.subs(x, 1)
        Integral(1, x)
        >>> at.subs(x, 1)
        Integral(x, (x, 1))

        The ``as_dummy`` method can be used to see which symbols cannot be
        targeted by subs: those with a preppended underscore cannot be
        changed with ``subs``. (Also, the integration variables themselves --
        the first element of a limit -- can never be changed by subs.)

        >>> i.as_dummy()
        Integral(x, x)
        >>> at.as_dummy()
        Integral(_x, (_x, x))

        """

        # Any embedded piecewise functions need to be brought out to the
        # top level so that integration can go into piecewise mode at the
        # earliest possible moment.
        function = piecewise_fold(sympify(function))

        if function is S.NaN:
            return S.NaN

        if symbols:
            limits, sign = _process_limits(*symbols)
        else:
            # no symbols provided -- let's compute full anti-derivative
            free = function.free_symbols
            if len(free) != 1:
                raise ValueError("specify variables of integration for %s" %
                                 function)
            limits, sign = [Tuple(s) for s in free], 1

        while isinstance(function, Integral):
            # denest the integrand
            limits = list(function.limits) + limits
            function = function.function

        obj = Expr.__new__(cls, **assumptions)
        arglist = [sign * function]
        arglist.extend(limits)
        obj._args = tuple(arglist)
        obj.is_commutative = all(s.is_commutative for s in obj.free_symbols)

        return obj
Beispiel #34
0
 def __new__(cls, setarg):
     return Expr.__new__(cls, setarg)
Beispiel #35
0
    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, 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] is S.Infinity:
                s = dict([(k, 1 / Dummy()) for k in variables])
                rs = dict([(1 / v, 1 / k) for k, v in s.items()])
            elif point[0] is not S.Zero:
                s = dict((k, Dummy() + point[0]) for k in variables)
                rs = dict((v - point[0], k - point[0]) for k, v in s.items())
            else:
                s = ()
                rs = ()

            expr = expr.subs(s)

            if expr.is_Add:
                from sympy 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_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_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_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
Beispiel #36
0
    def __new__(cls, expr, *symbols, **assumptions):
        expr = sympify(expr).expand()
        if expr is S.NaN:
            return S.NaN

        if symbols:
            symbols = map(sympify, symbols)
        else:
            symbols = list(expr.atoms(C.Symbol))

        symbols.sort(Basic.compare)

        if expr.is_Order:

            new_symbols = list(expr.symbols)
            for s in symbols:
                if s not in new_symbols:
                    new_symbols.append(s)
            if len(new_symbols)==len(expr.symbols):
                return expr
            symbols = new_symbols

        elif symbols:

            symbol_map = {}
            new_symbols = []
            for s in symbols:
                if isinstance(s, C.Symbol):
                    new_symbols.append(s)
                    continue
                z = C.Symbol('z',dummy=True)
                x1,s1 = solve4linearsymbol(s, z)
                expr = expr.subs(x1,s1)
                symbol_map[z] = s
                new_symbols.append(z)

            if symbol_map:
                r = Order(expr, *new_symbols, **assumptions)
                expr = r.expr.subs(symbol_map)
                symbols = []
                for s in r.symbols:
                    if symbol_map.has_key(s):
                        symbols.append(symbol_map[s])
                    else:
                        symbols.append(s)
            else:
                if expr.is_Add:
                    lst = expr.extract_leading_order(*symbols)
                    expr = C.Add(*[f.expr for (e,f) in lst])
                else:
                    expr = expr.as_leading_term(*symbols)
                    coeff, terms = expr.as_coeff_terms()
                    if coeff is S.Zero:
                        return coeff
                    expr = C.Mul(*[t for t in terms if t.has(*symbols)])

        elif expr is not S.Zero:
            expr = S.One

        if expr is S.Zero:
            return expr

        # create Order instance:
        obj = Expr.__new__(cls, expr, *symbols, **assumptions)

        return obj