示例#1
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def test_composite_option():
    assert construct_domain({(1,): sin(y)}, composite=False) == (EX, {(1,): EX(sin(y))})

    assert construct_domain({(1,): y}, composite=False) == (EX, {(1,): EX(y)})

    assert construct_domain({(1, 1): 1}, composite=False) == (ZZ, {(1, 1): 1})

    assert construct_domain({(1, 0): y}, composite=False) == (EX, {(1, 0): EX(y)})
示例#2
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def gegenbauer_poly(n, a, x=None, polys=False):
    """Generates Gegenbauer polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    a
        Decides minimal domain for the list of
        coefficients.
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError(
            "can't generate Gegenbauer polynomial of degree %s" % n)

    K, a = construct_domain(a, field=True)
    poly = DMP(dup_gegenbauer(int(n), a, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
示例#3
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def jacobi_poly(n, a, b, x=None, polys=False):
    """Generates Jacobi polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    a
        Lower limit of minimal domain for the list of
        coefficients.
    b
        Upper limit of minimal domain for the list of
        coefficients.
    x : optional
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Jacobi polynomial of degree %s" % n)

    K, v = construct_domain([a, b], field=True)
    poly = DMP(dup_jacobi(int(n), v[0], v[1], K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
示例#4
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def laguerre_poly(n, x=None, alpha=None, polys=False):
    """Generates Laguerre polynomial of degree `n` in `x`.

    Parameters
    ==========

    n : int
        `n` decides the degree of polynomial
    x : optional
    alpha
        Decides minimal domain for the list
        of coefficients.
    polys : bool, optional
        ``polys=True`` returns an expression, otherwise
        (default) returns an expression.
    """
    if n < 0:
        raise ValueError("can't generate Laguerre polynomial of degree %s" % n)

    if alpha is not None:
        K, alpha = construct_domain(
            alpha, field=True)  # XXX: ground_field=True
    else:
        K, alpha = QQ, QQ(0)

    poly = DMP(dup_laguerre(int(n), alpha, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    return poly if polys else poly.as_expr()
示例#5
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def test_precision():
    f1 = Float("1.01")
    f2 = Float("1.0000000000000000000001")
    for x in [1, 1e-2, 1e-6, 1e-13, 1e-14, 1e-16, 1e-20, 1e-100, 1e-300,
            f1, f2]:
        result = construct_domain([x])
        y = float(result[1][0])
        assert abs(x - y) / x < 1e-14  # Test relative accuracy

    result = construct_domain([f1])
    y = result[1][0]
    assert y-1 > 1e-50

    result = construct_domain([f2])
    y = result[1][0]
    assert y-1 > 1e-50
示例#6
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文件: fields.py 项目: asmeurer/sympy
def sfield(exprs, *symbols, **options):
    """Construct a field deriving generators and domain
    from options and input expressions.

    Parameters
    ==========

    exprs : :class:`Expr` or sequence of :class:`Expr` (sympifiable)
    symbols : sequence of :class:`Symbol`/:class:`Expr`
    options : keyword arguments understood by :class:`Options`

    Examples
    ========

    >>> from sympy.core import symbols
    >>> from sympy.functions import exp, log
    >>> from sympy.polys.fields import sfield

    >>> x = symbols("x")
    >>> K, f = sfield((x*log(x) + 4*x**2)*exp(1/x + log(x)/3)/x**2)
    >>> K
    Rational function field in x, exp(1/x), log(x), x**(1/3) over ZZ with lex order
    >>> f
    (4*x**2*(exp(1/x)) + x*(exp(1/x))*(log(x)))/((x**(1/3))**5)
    """
    single = False
    if not is_sequence(exprs):
        exprs, single = [exprs], True

    exprs = list(map(sympify, exprs))
    opt = build_options(symbols, options)
    numdens = []
    for expr in exprs:
        numdens.extend(expr.as_numer_denom())
    reps, opt = _parallel_dict_from_expr(numdens, opt)

    if opt.domain is None:
        # NOTE: this is inefficient because construct_domain() automatically
        # performs conversion to the target domain. It shouldn't do this.
        coeffs = sum([list(rep.values()) for rep in reps], [])
        opt.domain, _ = construct_domain(coeffs, opt=opt)

    _field = FracField(opt.gens, opt.domain, opt.order)
    fracs = []
    for i in range(0, len(reps), 2):
        fracs.append(_field(tuple(reps[i:i+2])))

    if single:
        return (_field, fracs[0])
    else:
        return (_field, fracs)
示例#7
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def jacobi_poly(n, a, b, x=None, **args):
    """Generates Jacobi polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Jacobi polynomial of degree %s" % n)

    K, v = construct_domain([a, b], field=True)
    poly = DMP(dup_jacobi(int(n), v[0], v[1], K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
示例#8
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def gegenbauer_poly(n, a, x=None, **args):
    """Generates Gegenbauer polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Gegenbauer polynomial of degree %s" % n)

    K, a = construct_domain(a, field=True)
    poly = DMP(dup_gegenbauer(int(n), a, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
示例#9
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def laguerre_poly(n, x=None, alpha=None, **args):
    """Generates Laguerre polynomial of degree `n` in `x`. """
    if n < 0:
        raise ValueError("can't generate Laguerre polynomial of degree %s" % n)

    if alpha is not None:
        K, alpha = construct_domain(alpha, field=True) # XXX: ground_field=True
    else:
        K, alpha = QQ, QQ(0)

    poly = DMP(dup_laguerre(int(n), alpha, K), K)

    if x is not None:
        poly = Poly.new(poly, x)
    else:
        poly = PurePoly.new(poly, Dummy('x'))

    if not args.get('polys', False):
        return poly.as_expr()
    else:
        return poly
示例#10
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def test_construct_domain():

    assert construct_domain([1, 2, 3]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([1, 2, 3], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)])

    assert construct_domain([S.One, S(2), S(3)]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([S.One, S(2), S(3)], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)])

    assert construct_domain([S.Half, S(2)]) == (QQ, [QQ(1, 2), QQ(2)])
    result = construct_domain([3.14, 1, S.Half])
    assert isinstance(result[0], RealField)
    assert result[1] == [RR(3.14), RR(1.0), RR(0.5)]

    result = construct_domain([3.14, I, S.Half])
    assert isinstance(result[0], ComplexField)
    assert result[1] == [CC(3.14), CC(1.0j), CC(0.5)]

    assert construct_domain([1, I]) == (ZZ_I, [ZZ_I(1, 0), ZZ_I(0, 1)])
    assert construct_domain([1, I/2]) == (QQ_I, [QQ_I(1, 0), QQ_I(0, S.Half)])

    assert construct_domain([3.14, sqrt(2)], extension=None) == (EX, [EX(3.14), EX(sqrt(2))])
    assert construct_domain([3.14, sqrt(2)], extension=True) == (EX, [EX(3.14), EX(sqrt(2))])

    assert construct_domain([1, sqrt(2)], extension=None) == (EX, [EX(1), EX(sqrt(2))])

    assert construct_domain([x, sqrt(x)]) == (EX, [EX(x), EX(sqrt(x))])
    assert construct_domain([x, sqrt(x), sqrt(y)]) == (EX, [EX(x), EX(sqrt(x)), EX(sqrt(y))])

    alg = QQ.algebraic_field(sqrt(2))

    assert construct_domain([7, S.Half, sqrt(2)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(S.Half), alg.convert(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2) + sqrt(3))

    assert construct_domain([7, sqrt(2), sqrt(3)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(sqrt(2)), alg.convert(sqrt(3))])

    dom = ZZ[x]

    assert construct_domain([2*x, 3]) == \
        (dom, [dom.convert(2*x), dom.convert(3)])

    dom = ZZ[x, y]

    assert construct_domain([2*x, 3*y]) == \
        (dom, [dom.convert(2*x), dom.convert(3*y)])

    dom = QQ[x]

    assert construct_domain([x/2, 3]) == \
        (dom, [dom.convert(x/2), dom.convert(3)])

    dom = QQ[x, y]

    assert construct_domain([x/2, 3*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3*y)])

    dom = ZZ_I[x]

    assert construct_domain([2*x, I]) == \
        (dom, [dom.convert(2*x), dom.convert(I)])

    dom = ZZ_I[x, y]

    assert construct_domain([2*x, I*y]) == \
        (dom, [dom.convert(2*x), dom.convert(I*y)])

    dom = QQ_I[x]

    assert construct_domain([x/2, I]) == \
        (dom, [dom.convert(x/2), dom.convert(I)])

    dom = QQ_I[x, y]

    assert construct_domain([x/2, I*y]) == \
        (dom, [dom.convert(x/2), dom.convert(I*y)])

    dom = RR[x]

    assert construct_domain([x/2, 3.5]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5)])

    dom = RR[x, y]

    assert construct_domain([x/2, 3.5*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5*y)])

    dom = CC[x]

    assert construct_domain([I*x/2, 3.5]) == \
        (dom, [dom.convert(I*x/2), dom.convert(3.5)])

    dom = CC[x, y]

    assert construct_domain([I*x/2, 3.5*y]) == \
        (dom, [dom.convert(I*x/2), dom.convert(3.5*y)])

    dom = CC[x]

    assert construct_domain([x/2, I*3.5]) == \
        (dom, [dom.convert(x/2), dom.convert(I*3.5)])

    dom = CC[x, y]

    assert construct_domain([x/2, I*3.5*y]) == \
        (dom, [dom.convert(x/2), dom.convert(I*3.5*y)])

    dom = ZZ.frac_field(x)

    assert construct_domain([2/x, 3]) == \
        (dom, [dom.convert(2/x), dom.convert(3)])

    dom = ZZ.frac_field(x, y)

    assert construct_domain([2/x, 3*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3*y)])

    dom = RR.frac_field(x)

    assert construct_domain([2/x, 3.5]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5)])

    dom = RR.frac_field(x, y)

    assert construct_domain([2/x, 3.5*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5*y)])

    dom = RealField(prec=336)[x]

    assert construct_domain([pi.evalf(100)*x]) == \
        (dom, [dom.convert(pi.evalf(100)*x)])

    assert construct_domain(2) == (ZZ, ZZ(2))
    assert construct_domain(S(2)/3) == (QQ, QQ(2, 3))
    assert construct_domain(Rational(2, 3)) == (QQ, QQ(2, 3))

    assert construct_domain({}) == (ZZ, {})
示例#11
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def test_issue_11538():
    for n in [E, pi, Catalan]:
        assert construct_domain(n)[0] == ZZ[n]
        assert construct_domain(x + n)[0] == ZZ[x, n]
    assert construct_domain(GoldenRatio)[0] == EX
    assert construct_domain(x + GoldenRatio)[0] == EX
示例#12
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def test_construct_domain():
    assert construct_domain([1, 2, 3]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([1, 2, 3],
                            field=True) == (QQ, [QQ(1), QQ(2),
                                                 QQ(3)])

    assert construct_domain([S(1), S(2), S(3)]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([S(1), S(2), S(3)],
                            field=True) == (QQ, [QQ(1), QQ(2),
                                                 QQ(3)])

    assert construct_domain([S(1) / 2, S(2)]) == (QQ, [QQ(1, 2), QQ(2)])
    result = construct_domain([3.14, 1, S(1) / 2])
    assert isinstance(result[0], RealField)
    assert result[1] == [RR(3.14), RR(1.0), RR(0.5)]

    assert construct_domain([3.14, sqrt(2)],
                            extension=None) == (EX, [EX(3.14),
                                                     EX(sqrt(2))])
    assert construct_domain([3.14, sqrt(2)],
                            extension=True) == (EX, [EX(3.14),
                                                     EX(sqrt(2))])

    assert construct_domain([1, sqrt(2)],
                            extension=None) == (EX, [EX(1), EX(sqrt(2))])

    assert construct_domain([x, sqrt(x)]) == (EX, [EX(x), EX(sqrt(x))])
    assert construct_domain([x, sqrt(x), sqrt(y)
                             ]) == (EX, [EX(x),
                                         EX(sqrt(x)),
                                         EX(sqrt(y))])

    alg = QQ.algebraic_field(sqrt(2))

    assert construct_domain([7, S(1)/2, sqrt(2)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(S(1)/2), alg.convert(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2) + sqrt(3))

    assert construct_domain([7, sqrt(2), sqrt(3)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(sqrt(2)), alg.convert(sqrt(3))])

    dom = ZZ[x]

    assert construct_domain([2*x, 3]) == \
        (dom, [dom.convert(2*x), dom.convert(3)])

    dom = ZZ[x, y]

    assert construct_domain([2*x, 3*y]) == \
        (dom, [dom.convert(2*x), dom.convert(3*y)])

    dom = QQ[x]

    assert construct_domain([x/2, 3]) == \
        (dom, [dom.convert(x/2), dom.convert(3)])

    dom = QQ[x, y]

    assert construct_domain([x/2, 3*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3*y)])

    dom = RR[x]

    assert construct_domain([x/2, 3.5]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5)])

    dom = RR[x, y]

    assert construct_domain([x/2, 3.5*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5*y)])

    dom = ZZ.frac_field(x)

    assert construct_domain([2/x, 3]) == \
        (dom, [dom.convert(2/x), dom.convert(3)])

    dom = ZZ.frac_field(x, y)

    assert construct_domain([2/x, 3*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3*y)])

    dom = RR.frac_field(x)

    assert construct_domain([2/x, 3.5]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5)])

    dom = RR.frac_field(x, y)

    assert construct_domain([2/x, 3.5*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5*y)])

    dom = RealField(prec=336)[x]

    assert construct_domain([pi.evalf(100)*x]) == \
        (dom, [dom.convert(pi.evalf(100)*x)])

    assert construct_domain(2) == (ZZ, ZZ(2))
    assert construct_domain(S(2) / 3) == (QQ, QQ(2, 3))

    assert construct_domain({}) == (ZZ, {})
示例#13
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    def _integrate(field=None):
        irreducibles = set()
        atans = set()
        pairs = set()

        for poly in reducibles:
            for z in poly.free_symbols:
                if z in V:
                    break  # should this be: `irreducibles |= \
            else:          # set(root_factors(poly, z, filter=field))`
                continue   # and the line below deleted?
                           #               |
                           #               V
            irreducibles |= set(root_factors(poly, z, filter=field))

        log_part, atan_part = [], []

        for poly in list(irreducibles):
            m = collect(poly, I, evaluate=False)
            y = m.get(I, S.Zero)
            if y:
                x = m.get(S.One, S.Zero)
                if x.has(I) or y.has(I):
                    continue  # nontrivial x + I*y
                pairs.add((x, y))
                irreducibles.remove(poly)

        while pairs:
            x, y = pairs.pop()
            if (x, -y) in pairs:
                pairs.remove((x, -y))
                # Choosing b with no minus sign
                if y.could_extract_minus_sign():
                    y = -y
                irreducibles.add(x*x + y*y)
                atans.add(atan(x/y))
            else:
                irreducibles.add(x + I*y)


        B = _symbols('B', len(irreducibles))
        C = _symbols('C', len(atans))

        # Note: the ordering matters here
        for poly, b in reversed(list(zip(ordered(irreducibles), B))):
            if poly.has(*V):
                poly_coeffs.append(b)
                log_part.append(b * log(poly))

        for poly, c in reversed(list(zip(ordered(atans), C))):
            if poly.has(*V):
                poly_coeffs.append(c)
                atan_part.append(c * poly)

        # TODO: Currently it's better to use symbolic expressions here instead
        # of rational functions, because it's simpler and FracElement doesn't
        # give big speed improvement yet. This is because cancellation is slow
        # due to slow polynomial GCD algorithms. If this gets improved then
        # revise this code.
        candidate = poly_part/poly_denom + Add(*log_part) + Add(*atan_part)
        h = F - _derivation(candidate) / denom
        raw_numer = h.as_numer_denom()[0]

        # Rewrite raw_numer as a polynomial in K[coeffs][V] where K is a field
        # that we have to determine. We can't use simply atoms() because log(3),
        # sqrt(y) and similar expressions can appear, leading to non-trivial
        # domains.
        syms = set(poly_coeffs) | set(V)
        non_syms = set()

        def find_non_syms(expr):
            if expr.is_Integer or expr.is_Rational:
                pass # ignore trivial numbers
            elif expr in syms:
                pass # ignore variables
            elif not expr.has(*syms):
                non_syms.add(expr)
            elif expr.is_Add or expr.is_Mul or expr.is_Pow:
                list(map(find_non_syms, expr.args))
            else:
                # TODO: Non-polynomial expression. This should have been
                # filtered out at an earlier stage.
                raise PolynomialError

        try:
            find_non_syms(raw_numer)
        except PolynomialError:
            return None
        else:
            ground, _ = construct_domain(non_syms, field=True)

        coeff_ring = PolyRing(poly_coeffs, ground)
        ring = PolyRing(V, coeff_ring)
        try:
            numer = ring.from_expr(raw_numer)
        except ValueError:
            raise PolynomialError
        solution = solve_lin_sys(numer.coeffs(), coeff_ring, _raw=False)

        if solution is None:
            return None
        else:
            return candidate.subs(solution).subs(
                list(zip(poly_coeffs, [S.Zero]*len(poly_coeffs))))
示例#14
0
def test_construct_domain():
    assert construct_domain([1, 2, 3]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([1, 2, 3],
                            field=True) == (QQ, [QQ(1), QQ(2),
                                                 QQ(3)])

    assert construct_domain([S(1), S(2), S(3)]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([S(1), S(2), S(3)],
                            field=True) == (QQ, [QQ(1), QQ(2),
                                                 QQ(3)])

    assert construct_domain([S(1) / 2, S(2)]) == (QQ, [QQ(1, 2), QQ(2)])
    assert construct_domain([3.14, 1,
                             S(1) / 2]) == (RR, [RR(3.14),
                                                 RR(1.0),
                                                 RR(0.5)])

    assert construct_domain([3.14, sqrt(2)],
                            extension=None) == (EX, [EX(3.14),
                                                     EX(sqrt(2))])
    assert construct_domain([3.14, sqrt(2)],
                            extension=True) == (EX, [EX(3.14),
                                                     EX(sqrt(2))])

    assert construct_domain([1, sqrt(2)],
                            extension=None) == (EX, [EX(1), EX(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2))

    assert construct_domain([7, S(1)/2, sqrt(2)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(S(1)/2), alg.convert(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2) + sqrt(3))

    assert construct_domain([7, sqrt(2), sqrt(3)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(sqrt(2)), alg.convert(sqrt(3))])

    dom = ZZ[x]

    assert construct_domain([2*x, 3]) == \
        (dom, [dom.convert(2*x), dom.convert(3)])

    dom = ZZ[x, y]

    assert construct_domain([2*x, 3*y]) == \
        (dom, [dom.convert(2*x), dom.convert(3*y)])

    dom = QQ[x]

    assert construct_domain([x/2, 3]) == \
        (dom, [dom.convert(x/2), dom.convert(3)])

    dom = QQ[x, y]

    assert construct_domain([x/2, 3*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3*y)])

    dom = RR[x]

    assert construct_domain([x/2, 3.5]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5)])

    dom = RR[x, y]

    assert construct_domain([x/2, 3.5*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5*y)])

    dom = ZZ.frac_field(x)

    assert construct_domain([2/x, 3]) == \
        (dom, [dom.convert(2/x), dom.convert(3)])

    dom = ZZ.frac_field(x, y)

    assert construct_domain([2/x, 3*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3*y)])
示例#15
0
def test_construct_domain():
    assert construct_domain([1, 2, 3]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain(
        [1, 2, 3], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)])

    assert construct_domain([S(1), S(2), S(3)]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain(
        [S(1), S(2), S(3)], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)])

    assert construct_domain([S(1)/2, S(2)]) == (QQ, [QQ(1, 2), QQ(2)])
    assert construct_domain(
        [3.14, 1, S(1)/2]) == (RR, [RR(3.14), RR(1.0), RR(0.5)])

    assert construct_domain(
        [3.14, sqrt(2)], extension=None) == (EX, [EX(3.14), EX(sqrt(2))])
    assert construct_domain(
        [3.14, sqrt(2)], extension=True) == (EX, [EX(3.14), EX(sqrt(2))])

    assert construct_domain(
        [1, sqrt(2)], extension=None) == (EX, [EX(1), EX(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2))

    assert construct_domain([7, S(1)/2, sqrt(2)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(S(1)/2), alg.convert(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2) + sqrt(3))

    assert construct_domain([7, sqrt(2), sqrt(3)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(sqrt(2)), alg.convert(sqrt(3))])

    dom = ZZ[x]

    assert construct_domain([2*x, 3]) == \
        (dom, [dom.convert(2*x), dom.convert(3)])

    dom = ZZ[x, y]

    assert construct_domain([2*x, 3*y]) == \
        (dom, [dom.convert(2*x), dom.convert(3*y)])

    dom = QQ[x]

    assert construct_domain([x/2, 3]) == \
        (dom, [dom.convert(x/2), dom.convert(3)])

    dom = QQ[x, y]

    assert construct_domain([x/2, 3*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3*y)])

    dom = RR[x]

    assert construct_domain([x/2, 3.5]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5)])

    dom = RR[x, y]

    assert construct_domain([x/2, 3.5*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5*y)])

    dom = ZZ.frac_field(x)

    assert construct_domain([2/x, 3]) == \
        (dom, [dom.convert(2/x), dom.convert(3)])

    dom = ZZ.frac_field(x, y)

    assert construct_domain([2/x, 3*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3*y)])

    dom = RR.frac_field(x)

    assert construct_domain([2/x, 3.5]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5)])

    dom = RR.frac_field(x, y)

    assert construct_domain([2/x, 3.5*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5*y)])

    assert construct_domain(2) == (ZZ, ZZ(2))
    assert construct_domain(S(2)/3) == (QQ, QQ(2, 3))
示例#16
0
 def get_domain(cls, items_sympy, **kwargs):
     K, items_K = construct_domain(items_sympy, **kwargs)
     return K, items_K
示例#17
0
文件: heurisch.py 项目: sympy/sympy
    def _integrate(field=None):
        irreducibles = set()
        atans = set()
        pairs = set()

        for poly in reducibles:
            for z in poly.free_symbols:
                if z in V:
                    break  # should this be: `irreducibles |= \
            else:          # set(root_factors(poly, z, filter=field))`
                continue   # and the line below deleted?
                           #               |
                           #               V
            irreducibles |= set(root_factors(poly, z, filter=field))

        log_part, atan_part = [], []

        for poly in list(irreducibles):
            m = collect(poly, I, evaluate=False)
            y = m.get(I, S.Zero)
            if y:
                x = m.get(S.One, S.Zero)
                if x.has(I) or y.has(I):
                    continue  # nontrivial x + I*y
                pairs.add((x, y))
                irreducibles.remove(poly)

        while pairs:
            x, y = pairs.pop()
            if (x, -y) in pairs:
                pairs.remove((x, -y))
                # Choosing b with no minus sign
                if y.could_extract_minus_sign():
                    y = -y
                irreducibles.add(x*x + y*y)
                atans.add(atan(x/y))
            else:
                irreducibles.add(x + I*y)


        B = _symbols('B', len(irreducibles))
        C = _symbols('C', len(atans))

        # Note: the ordering matters here
        for poly, b in reversed(list(ordered(zip(irreducibles, B)))):
            if poly.has(*V):
                poly_coeffs.append(b)
                log_part.append(b * log(poly))

        for poly, c in reversed(list(ordered(zip(atans, C)))):
            if poly.has(*V):
                poly_coeffs.append(c)
                atan_part.append(c * poly)

        # TODO: Currently it's better to use symbolic expressions here instead
        # of rational functions, because it's simpler and FracElement doesn't
        # give big speed improvement yet. This is because cancellation is slow
        # due to slow polynomial GCD algorithms. If this gets improved then
        # revise this code.
        candidate = poly_part/poly_denom + Add(*log_part) + Add(*atan_part)
        h = F - _derivation(candidate) / denom
        raw_numer = h.as_numer_denom()[0]

        # Rewrite raw_numer as a polynomial in K[coeffs][V] where K is a field
        # that we have to determine. We can't use simply atoms() because log(3),
        # sqrt(y) and similar expressions can appear, leading to non-trivial
        # domains.
        syms = set(poly_coeffs) | set(V)
        non_syms = set([])

        def find_non_syms(expr):
            if expr.is_Integer or expr.is_Rational:
                pass # ignore trivial numbers
            elif expr in syms:
                pass # ignore variables
            elif not expr.has(*syms):
                non_syms.add(expr)
            elif expr.is_Add or expr.is_Mul or expr.is_Pow:
                list(map(find_non_syms, expr.args))
            else:
                # TODO: Non-polynomial expression. This should have been
                # filtered out at an earlier stage.
                raise PolynomialError

        try:
            find_non_syms(raw_numer)
        except PolynomialError:
            return None
        else:
            ground, _ = construct_domain(non_syms, field=True)

        coeff_ring = PolyRing(poly_coeffs, ground)
        ring = PolyRing(V, coeff_ring)
        try:
            numer = ring.from_expr(raw_numer)
        except ValueError:
            raise PolynomialError
        solution = solve_lin_sys(numer.coeffs(), coeff_ring, _raw=False)

        if solution is None:
            return None
        else:
            return candidate.subs(solution).subs(
                list(zip(poly_coeffs, [S.Zero]*len(poly_coeffs))))
示例#18
0
def test_issue_11538():
    for n in [E, pi, Catalan]:
        assert construct_domain(n)[0] == ZZ[n]
        assert construct_domain(x + n)[0] == ZZ[x, n]
    assert construct_domain(GoldenRatio)[0] == EX
    assert construct_domain(x + GoldenRatio)[0] == EX
示例#19
0
def test_construct_domain():
    assert construct_domain([1, 2, 3]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([1, 2, 3], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)])

    assert construct_domain([S(1), S(2), S(3)]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)])
    assert construct_domain([S(1), S(2), S(3)], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)])

    assert construct_domain([S(1)/2, S(2)]) == (QQ, [QQ(1, 2), QQ(2)])
    result = construct_domain([3.14, 1, S(1)/2])
    assert isinstance(result[0], RealField)
    assert result[1] == [RR(3.14), RR(1.0), RR(0.5)]

    assert construct_domain([3.14, sqrt(2)], extension=None) == (EX, [EX(3.14), EX(sqrt(2))])
    assert construct_domain([3.14, sqrt(2)], extension=True) == (EX, [EX(3.14), EX(sqrt(2))])

    assert construct_domain([1, sqrt(2)], extension=None) == (EX, [EX(1), EX(sqrt(2))])

    assert construct_domain([x, sqrt(x)]) == (EX, [EX(x), EX(sqrt(x))])
    assert construct_domain([x, sqrt(x), sqrt(y)]) == (EX, [EX(x), EX(sqrt(x)), EX(sqrt(y))])

    alg = QQ.algebraic_field(sqrt(2))

    assert construct_domain([7, S(1)/2, sqrt(2)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(S(1)/2), alg.convert(sqrt(2))])

    alg = QQ.algebraic_field(sqrt(2) + sqrt(3))

    assert construct_domain([7, sqrt(2), sqrt(3)], extension=True) == \
        (alg, [alg.convert(7), alg.convert(sqrt(2)), alg.convert(sqrt(3))])

    dom = ZZ[x]

    assert construct_domain([2*x, 3]) == \
        (dom, [dom.convert(2*x), dom.convert(3)])

    dom = ZZ[x, y]

    assert construct_domain([2*x, 3*y]) == \
        (dom, [dom.convert(2*x), dom.convert(3*y)])

    dom = QQ[x]

    assert construct_domain([x/2, 3]) == \
        (dom, [dom.convert(x/2), dom.convert(3)])

    dom = QQ[x, y]

    assert construct_domain([x/2, 3*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3*y)])

    dom = RR[x]

    assert construct_domain([x/2, 3.5]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5)])

    dom = RR[x, y]

    assert construct_domain([x/2, 3.5*y]) == \
        (dom, [dom.convert(x/2), dom.convert(3.5*y)])

    dom = ZZ.frac_field(x)

    assert construct_domain([2/x, 3]) == \
        (dom, [dom.convert(2/x), dom.convert(3)])

    dom = ZZ.frac_field(x, y)

    assert construct_domain([2/x, 3*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3*y)])

    dom = RR.frac_field(x)

    assert construct_domain([2/x, 3.5]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5)])

    dom = RR.frac_field(x, y)

    assert construct_domain([2/x, 3.5*y]) == \
        (dom, [dom.convert(2/x), dom.convert(3.5*y)])

    dom = RealField(prec=336)[x]

    assert construct_domain([pi.evalf(100)*x]) == \
        (dom, [dom.convert(pi.evalf(100)*x)])

    assert construct_domain(2) == (ZZ, ZZ(2))
    assert construct_domain(S(2)/3) == (QQ, QQ(2, 3))

    assert construct_domain({}) == (ZZ, {})
示例#20
0
文件: heurisch.py 项目: AALEKH/sympy
    def _integrate(field=None):
        irreducibles = set()

        for poly in reducibles:
            for z in poly.atoms(Symbol):
                if z in V:
                    break
            else:
                continue

            irreducibles |= set(root_factors(poly, z, filter=field))

        log_coeffs, log_part = [], []
        B = _symbols('B', len(irreducibles))

        for i, poly in enumerate(irreducibles):
            if poly.has(*V):
                log_coeffs.append(B[i])
                log_part.append(log_coeffs[-1] * log(poly))

        coeffs = poly_coeffs + log_coeffs

        # TODO: Currently it's better to use symbolic expressions here instead
        # of rational functions, because it's simpler and FracElement doesn't
        # give big speed improvement yet. This is because cancelation is slow
        # due to slow polynomial GCD algorithms. If this gets improved then
        # revise this code.
        candidate = poly_part/poly_denom + Add(*log_part)
        h = F - _derivation(candidate) / denom
        raw_numer = h.as_numer_denom()[0]

        # Rewrite raw_numer as a polynomial in K[coeffs][V] where K is a field
        # that we have to determine. We can't use simply atoms() because log(3),
        # sqrt(y) and similar expressions can appear, leading to non-trivial
        # domains.
        syms = set(coeffs) | set(V)
        non_syms = set([])

        def find_non_syms(expr):
            if expr.is_Integer or expr.is_Rational:
                pass # ignore trivial numbers
            elif expr in syms:
                pass # ignore variables
            elif not expr.has(*syms):
                non_syms.add(expr)
            elif expr.is_Add or expr.is_Mul or expr.is_Pow:
                list(map(find_non_syms, expr.args))
            else:
                # TODO: Non-polynomial expression. This should have been
                # filtered out at an earlier stage.
                raise PolynomialError

        try:
            find_non_syms(raw_numer)
        except PolynomialError:
            return None
        else:
            ground, _ = construct_domain(non_syms, field=True)

        coeff_ring = PolyRing(coeffs, ground)
        ring = PolyRing(V, coeff_ring)

        numer = ring.from_expr(raw_numer)

        solution = solve_lin_sys(numer.coeffs(), coeff_ring)

        if solution is None:
            return None
        else:
            solution = [ (k.as_expr(), v.as_expr()) for k, v in solution.items() ]
            return candidate.subs(solution).subs(list(zip(coeffs, [S.Zero]*len(coeffs))))
示例#21
0
    def _integrate(field=None):
        irreducibles = set()

        for poly in reducibles:
            for z in poly.free_symbols:
                if z in V:
                    break  # should this be: `irreducibles |= \
            else:  # set(root_factors(poly, z, filter=field))`
                continue  # and the line below deleted?
                #               |
                #               V
            irreducibles |= set(root_factors(poly, z, filter=field))

        log_coeffs, log_part = [], []
        B = _symbols('B', len(irreducibles))

        # Note: the ordering matters here
        for poly, b in reversed(list(ordered(zip(irreducibles, B)))):
            if poly.has(*V):
                poly_coeffs.append(b)
                log_part.append(b * log(poly))

        # TODO: Currently it's better to use symbolic expressions here instead
        # of rational functions, because it's simpler and FracElement doesn't
        # give big speed improvement yet. This is because cancelation is slow
        # due to slow polynomial GCD algorithms. If this gets improved then
        # revise this code.
        candidate = poly_part / poly_denom + Add(*log_part)
        h = F - _derivation(candidate) / denom
        raw_numer = h.as_numer_denom()[0]

        # Rewrite raw_numer as a polynomial in K[coeffs][V] where K is a field
        # that we have to determine. We can't use simply atoms() because log(3),
        # sqrt(y) and similar expressions can appear, leading to non-trivial
        # domains.
        syms = set(poly_coeffs) | set(V)
        non_syms = set([])

        def find_non_syms(expr):
            if expr.is_Integer or expr.is_Rational:
                pass  # ignore trivial numbers
            elif expr in syms:
                pass  # ignore variables
            elif not expr.has(*syms):
                non_syms.add(expr)
            elif expr.is_Add or expr.is_Mul or expr.is_Pow:
                list(map(find_non_syms, expr.args))
            else:
                # TODO: Non-polynomial expression. This should have been
                # filtered out at an earlier stage.
                raise PolynomialError

        try:
            find_non_syms(raw_numer)
        except PolynomialError:
            return None
        else:
            ground, _ = construct_domain(non_syms, field=True)

        coeff_ring = PolyRing(poly_coeffs, ground)
        ring = PolyRing(V, coeff_ring)

        numer = ring.from_expr(raw_numer)

        solution = solve_lin_sys(numer.coeffs(), coeff_ring, _raw=False)

        if solution is None:
            return None
        else:
            return candidate.subs(solution).subs(
                list(zip(poly_coeffs, [S.Zero] * len(poly_coeffs))))