def _eval_simplify(self, ratio=1.7, measure=None, rational=False, inverse=False):
        from sympy.simplify.simplify import factor_sum, sum_combine
        from sympy.core.function import expand
        from sympy.core.mul import Mul

        # split the function into adds
        terms = Add.make_args(expand(self.function))
        s_t = [] # Sum Terms
        o_t = [] # Other Terms

        for term in terms:
            if term.has(Sum):
                # if there is an embedded sum here
                # it is of the form x * (Sum(whatever))
                # hence we make a Mul out of it, and simplify all interior sum terms
                subterms = Mul.make_args(expand(term))
                out_terms = []
                for subterm in subterms:
                    # go through each term
                    if isinstance(subterm, Sum):
                        # if it's a sum, simplify it
                        out_terms.append(subterm._eval_simplify())
                    else:
                        # otherwise, add it as is
                        out_terms.append(subterm)

                # turn it back into a Mul
                s_t.append(Mul(*out_terms))
            else:
                o_t.append(term)

        # next try to combine any interior sums for further simplification
        result = Add(sum_combine(s_t), *o_t)

        return factor_sum(result, limits=self.limits)
Exemplo n.º 2
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    def _eval_simplify(self, ratio=1.7, measure=None):
        from sympy.simplify.simplify import factor_sum, sum_combine
        from sympy.core.function import expand
        from sympy.core.mul import Mul

        # split the function into adds
        terms = Add.make_args(expand(self.function))
        s_t = [] # Sum Terms
        o_t = [] # Other Terms

        for term in terms:
            if term.has(Sum):
                # if there is an embedded sum here
                # it is of the form x * (Sum(whatever))
                # hence we make a Mul out of it, and simplify all interior sum terms
                subterms = Mul.make_args(expand(term))
                out_terms = []
                for subterm in subterms:
                    # go through each term
                    if isinstance(subterm, Sum):
                        # if it's a sum, simplify it
                        out_terms.append(subterm._eval_simplify())
                    else:
                        # otherwise, add it as is
                        out_terms.append(subterm)

                # turn it back into a Mul
                s_t.append(Mul(*out_terms))
            else:
                o_t.append(term)

        # next try to combine any interior sums for further simplification
        result = Add(sum_combine(s_t), *o_t)

        return factor_sum(result, limits=self.limits)
Exemplo n.º 3
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    def do(expr):
        from sympy.concrete.summations import Sum
        from sympy.simplify.simplify import factor_sum
        is_iterable = iterable(expr)

        if not isinstance(expr, Basic) or expr.is_Atom:
            if is_iterable:
                return type(expr)([do(i) for i in expr])
            return expr

        if expr.is_Pow or expr.is_Function or \
                is_iterable or not hasattr(expr, 'args_cnc'):
            args = expr.args
            newargs = tuple([do(i) for i in args])
            if newargs == args:
                return expr
            return expr.func(*newargs)

        if isinstance(expr, Sum):
            return factor_sum(expr,
                              radical=radical,
                              clear=clear,
                              fraction=fraction,
                              sign=sign)

        cont, p = expr.as_content_primitive(radical=radical, clear=clear)
        if p.is_Add:
            list_args = [do(a) for a in Add.make_args(p)]
            # get a common negative (if there) which gcd_terms does not remove
            if all(a.as_coeff_Mul()[0].extract_multiplicatively(-1) is not None
                   for a in list_args):
                cont = -cont
                list_args = [-a for a in list_args]
            # watch out for exp(-(x+2)) which gcd_terms will change to exp(-x-2)
            special = {}
            for i, a in enumerate(list_args):
                b, e = a.as_base_exp()
                if e.is_Mul and e != Mul(*e.args):
                    list_args[i] = Dummy()
                    special[list_args[i]] = a
            # rebuild p not worrying about the order which gcd_terms will fix
            p = Add._from_args(list_args)
            p = gcd_terms(p, isprimitive=True, clear=clear,
                          fraction=fraction).xreplace(special)
        elif p.args:
            p = p.func(*[do(a) for a in p.args])
        rv = _keep_coeff(cont, p, clear=clear, sign=sign)
        return rv
Exemplo n.º 4
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    def do(expr):
        from sympy.concrete.summations import Sum
        from sympy.simplify.simplify import factor_sum
        is_iterable = iterable(expr)

        if not isinstance(expr, Basic) or expr.is_Atom:
            if is_iterable:
                return type(expr)([do(i) for i in expr])
            return expr

        if expr.is_Pow or expr.is_Function or \
                is_iterable or not hasattr(expr, 'args_cnc'):
            args = expr.args
            newargs = tuple([do(i) for i in args])
            if newargs == args:
                return expr
            return expr.func(*newargs)

        if isinstance(expr, Sum):
            return factor_sum(expr, radical=radical, clear=clear, fraction=fraction, sign=sign)

        cont, p = expr.as_content_primitive(radical=radical, clear=clear)
        if p.is_Add:
            list_args = [do(a) for a in Add.make_args(p)]
            # get a common negative (if there) which gcd_terms does not remove
            if all(a.as_coeff_Mul()[0].extract_multiplicatively(-1) is not None
                   for a in list_args):
                cont = -cont
                list_args = [-a for a in list_args]
            # watch out for exp(-(x+2)) which gcd_terms will change to exp(-x-2)
            special = {}
            for i, a in enumerate(list_args):
                b, e = a.as_base_exp()
                if e.is_Mul and e != Mul(*e.args):
                    list_args[i] = Dummy()
                    special[list_args[i]] = a
            # rebuild p not worrying about the order which gcd_terms will fix
            p = Add._from_args(list_args)
            p = gcd_terms(p,
                isprimitive=True,
                clear=clear,
                fraction=fraction).xreplace(special)
        elif p.args:
            p = p.func(
                *[do(a) for a in p.args])
        rv = _keep_coeff(cont, p, clear=clear, sign=sign)
        return rv