当前位置: 首页>>代码示例>>Python>>正文


Python Add.as_independent方法代码示例

本文整理汇总了Python中sympy.core.Add.as_independent方法的典型用法代码示例。如果您正苦于以下问题:Python Add.as_independent方法的具体用法?Python Add.as_independent怎么用?Python Add.as_independent使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在sympy.core.Add的用法示例。


在下文中一共展示了Add.as_independent方法的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。

示例1: __new__

# 需要导入模块: from sympy.core import Add [as 别名]
# 或者: from sympy.core.Add import as_independent [as 别名]
    def __new__(cls, expr, *symbols):

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

        point = S.Zero
        if symbols:
            symbols = list(map(sympify, symbols))
            if symbols[-1] in (S.Infinity, S.Zero):
                point = symbols[-1]
                symbols = symbols[:-1]
            if not all(isinstance(s, Symbol) for s in symbols):
                raise NotImplementedError(
                    'Order at points other than 0 or oo not supported.')
        if not symbols:
            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))
            args = tuple(symbols) + (point,)

            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(*args)
                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=default_sort_key)
        args = (expr,) + tuple(symbols) + (point,)
        obj = Expr.__new__(cls, *args)
        return obj
开发者ID:QuaBoo,项目名称:sympy,代码行数:90,代码来源:order.py

示例2: __new__

# 需要导入模块: from sympy.core import Add [as 别名]
# 或者: from sympy.core.Add import as_independent [as 别名]
    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 not all(p is S.Zero for p in point) and \
           not all(p is S.Infinity for p in point):
            raise NotImplementedError('Order at points other than 0 '
                'or oo not supported, got %s as a point.' % point)

        if 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(variables, point)
                expr = Add(*[f.expr for (e, f) in lst])

            elif expr:
                if point[0] == S.Zero:
                    expr = expr.as_leading_term(*variables)
                expr = expr.as_independent(*variables, as_Add=False)[1]

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

                if len(variables) == 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 = variables[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)

#.........这里部分代码省略.........
开发者ID:Amo10,项目名称:Computer-Science-2014-2015,代码行数:103,代码来源:order.py

示例3: __new__

# 需要导入模块: from sympy.core import Add [as 别名]
# 或者: from sympy.core.Add import as_independent [as 别名]
    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:
            v = set(expr.variables)
            symbols = v | set(symbols)
            if symbols == v:
                return expr
            symbols = list(symbols)

        elif symbols:

            symbols = list(set(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])

                margs = list(Mul.make_args(expr.as_independent(*symbols)[1]))

                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]

                    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
开发者ID:yuriy-demidov,项目名称:sympy,代码行数:79,代码来源:order.py


注:本文中的sympy.core.Add.as_independent方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。