Esempio n. 1
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def test_solve_biquadratic():
    x0, y0, x1, y1, r = symbols('x0 y0 x1 y1 r')

    f_1 = (x - 1)**2 + (y - 1)**2 - r**2
    f_2 = (x - 2)**2 + (y - 2)**2 - r**2

    assert solve_poly_system([f_1, f_2], x, y) == \
        [(Rational(3, 2) - sqrt(-1 + 2*r**2)/2, Rational(3, 2) + sqrt(-1 + 2*r**2)/2),
         (Rational(3, 2) + sqrt(-1 + 2*r**2)/2, Rational(3, 2) - sqrt(-1 + 2*r**2)/2)]

    f_1 = (x - 1)**2 + (y - 2)**2 - r**2
    f_2 = (x - 1)**2 + (y - 1)**2 - r**2

    assert solve_poly_system([f_1, f_2], x, y) == \
        [(1 - sqrt(((2*r - 1)*(2*r + 1)))/2, Rational(3, 2)),
         (1 + sqrt(((2*r - 1)*(2*r + 1)))/2, Rational(3, 2))]

    def query(expr):
        return expr.is_Pow and expr.exp is S.Half

    f_1 = (x - 1 )**2 + (y - 2)**2 - r**2
    f_2 = (x - x1)**2 + (y - 1)**2 - r**2

    result = solve_poly_system([f_1, f_2], x, y)

    assert len(result) == 2 and all(len(r) == 2 for r in result)
    assert all(r.count(query) == 1 for r in flatten(result))

    f_1 = (x - x0)**2 + (y - y0)**2 - r**2
    f_2 = (x - x1)**2 + (y - y1)**2 - r**2

    result = solve_poly_system([f_1, f_2], x, y)

    assert len(result) == 2 and all(len(r) == 2 for r in result)
    assert all(len(r.find(query)) == 1 for r in flatten(result))
Esempio n. 2
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def test_solve_biquadratic():
    x0, y0, x1, y1, r = symbols('x0 y0 x1 y1 r')

    f_1 = (x - 1)**2 + (y - 1)**2 - r**2
    f_2 = (x - 2)**2 + (y - 2)**2 - r**2

    assert (solve_poly_system([f_1, f_2], x, y) ==
            [{x: Rational(3, 2) - sqrt(-1 + 2*r**2)/2,
              y: Rational(3, 2) + sqrt(-1 + 2*r**2)/2},
             {x: Rational(3, 2) + sqrt(-1 + 2*r**2)/2,
              y: Rational(3, 2) - sqrt(-1 + 2*r**2)/2}])

    f_1 = (x - 1)**2 + (y - 2)**2 - r**2
    f_2 = (x - 1)**2 + (y - 1)**2 - r**2

    assert (solve_poly_system([f_1, f_2], x, y) ==
            [{x: 1 - sqrt(((2*r - 1)*(2*r + 1)))/2, y: Rational(3, 2)},
             {x: 1 + sqrt(((2*r - 1)*(2*r + 1)))/2, y: Rational(3, 2)}])

    def query(expr):
        return expr.is_Pow and expr.exp is S.Half

    f_1 = (x - 1 )**2 + (y - 2)**2 - r**2
    f_2 = (x - x1)**2 + (y - 1)**2 - r**2

    result = [tuple(r.values()) for r in solve_poly_system([f_1, f_2], x, y)]

    assert len(result) == 2 and all(len(r) == 2 for r in result)
    assert all(r.count(query) == 1 for r in flatten(result))

    f_1 = (x - x0)**2 + (y - y0)**2 - r**2
    f_2 = (x - x1)**2 + (y - y1)**2 - r**2

    result = [tuple(r.values()) for r in solve_poly_system([f_1, f_2], x, y)]

    assert len(result) == 2 and all(len(r) == 2 for r in result)
    assert all(len(r.find(query)) == 1 for r in flatten(result))

    eqs = [y**2 - 4 + x, y*2 + 3*x - 7]
    assert solve_poly_system(eqs, x, y) == [{x: Rational(11, 9),
                                             y: Rational(5, 3)},
                                            {x: 3, y: -1}]
    eqs = [y + x**2 - 3, -y + x - 4]
    assert solve_poly_system(eqs, x, y) == [{x: -S.Half + sqrt(29)/2,
                                             y: Rational(-9, 2) + sqrt(29)/2},
                                            {x: -sqrt(29)/2 - S.Half,
                                             y: Rational(-9, 2) - sqrt(29)/2}]
Esempio n. 3
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 def _new(cls, *args, **kwargs):
     shape, flat_list = cls._handle_ndarray_creation_inputs(*args, **kwargs)
     flat_list = flatten(flat_list)
     self = object.__new__(cls)
     self._shape = shape
     self._array = list(flat_list)
     self._rank = len(shape)
     self._loop_size = functools.reduce(lambda x, y: x * y,
                                        shape) if shape else 0
     return self
Esempio n. 4
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def test_flatten():
    assert flatten((1, (1,))) == [1, 1]
    assert flatten((x, (x,))) == [x, x]

    ls = [[(-2, -1), (1, 2)], [(0, 0)]]

    assert flatten(ls, levels=0) == ls
    assert flatten(ls, levels=1) == [(-2, -1), (1, 2), (0, 0)]
    assert flatten(ls, levels=2) == [-2, -1, 1, 2, 0, 0]
    assert flatten(ls, levels=3) == [-2, -1, 1, 2, 0, 0]

    pytest.raises(ValueError, lambda: flatten(ls, levels=-1))

    class MyOp(Basic):
        pass

    assert flatten([MyOp(x, y), z]) == [MyOp(x, y), z]
    assert flatten([MyOp(x, y), z], cls=MyOp) == [x, y, z]

    assert flatten({1, 11, 2}) == list({1, 11, 2})
Esempio n. 5
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 def _new(cls, *args, **kwargs):
     shape, flat_list = cls._handle_ndarray_creation_inputs(*args, **kwargs)
     shape = Tuple(*map(_sympify, shape))
     flat_list = flatten(flat_list)
     flat_list = Tuple(*flat_list)
     self = Basic.__new__(cls, flat_list, shape, **kwargs)
     self._shape = shape
     self._array = tuple(flat_list)
     self._rank = len(shape)
     self._loop_size = functools.reduce(lambda x, y: x * y,
                                        shape) if shape else 0
     return self
Esempio n. 6
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    def __new__(cls, *args, **kwargs):

        shape, flat_list = cls._handle_ndarray_creation_inputs(*args, **kwargs)
        self = object.__new__(cls)
        self._shape = shape
        self._rank = len(shape)
        self._loop_size = functools.reduce(lambda x, y: x * y,
                                           shape) if shape else 0

        # Sparse array:
        if isinstance(flat_list, (dict, Dict)):
            self._sparse_array = dict(flat_list)
            return self

        self._sparse_array = {}

        for i, el in enumerate(flatten(flat_list)):
            if el != 0:
                self._sparse_array[i] = _sympify(el)

        return self
Esempio n. 7
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    def __new__(cls, *args, **kwargs):

        shape, flat_list = cls._handle_ndarray_creation_inputs(*args, **kwargs)
        shape = Tuple(*map(_sympify, shape))
        loop_size = functools.reduce(lambda x, y: x * y, shape) if shape else 0

        # Sparse array:
        if isinstance(flat_list, (dict, Dict)):
            sparse_array = Dict(flat_list)
        else:
            sparse_array = {}
            for i, el in enumerate(flatten(flat_list)):
                if el != 0:
                    sparse_array[i] = _sympify(el)

        sparse_array = Dict(sparse_array)

        self = Expr.__new__(cls, sparse_array, shape, **kwargs)
        self._shape = shape
        self._rank = len(shape)
        self._loop_size = loop_size
        self._sparse_array = sparse_array

        return self
Esempio n. 8
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def test_solve_biquadratic():
    x0, y0, x1, y1, r = symbols('x0 y0 x1 y1 r')

    f_1 = (x - 1)**2 + (y - 1)**2 - r**2
    f_2 = (x - 2)**2 + (y - 2)**2 - r**2

    assert (solve_poly_system([f_1, f_2], x, y) == [{
        x:
        Rational(3, 2) - sqrt(-1 + 2 * r**2) / 2,
        y:
        Rational(3, 2) + sqrt(-1 + 2 * r**2) / 2
    }, {
        x:
        Rational(3, 2) + sqrt(-1 + 2 * r**2) / 2,
        y:
        Rational(3, 2) - sqrt(-1 + 2 * r**2) / 2
    }])

    f_1 = (x - 1)**2 + (y - 2)**2 - r**2
    f_2 = (x - 1)**2 + (y - 1)**2 - r**2

    assert (solve_poly_system([f_1, f_2], x, y) == [{
        x:
        1 - sqrt(((2 * r - 1) * (2 * r + 1))) / 2,
        y:
        Rational(3, 2)
    }, {
        x:
        1 + sqrt(((2 * r - 1) * (2 * r + 1))) / 2,
        y:
        Rational(3, 2)
    }])

    def query(expr):
        return expr.is_Pow and expr.exp is Rational(1, 2)

    f_1 = (x - 1)**2 + (y - 2)**2 - r**2
    f_2 = (x - x1)**2 + (y - 1)**2 - r**2

    result = [tuple(r.values()) for r in solve_poly_system([f_1, f_2], x, y)]

    assert len(result) == 2 and all(len(r) == 2 for r in result)
    assert all(r.count(query) == 1 for r in flatten(result))

    f_1 = (x - x0)**2 + (y - y0)**2 - r**2
    f_2 = (x - x1)**2 + (y - y1)**2 - r**2

    result = [tuple(r.values()) for r in solve_poly_system([f_1, f_2], x, y)]

    assert len(result) == 2 and all(len(r) == 2 for r in result)
    assert all(len(r.find(query)) == 1 for r in flatten(result))

    eqs = [y**2 - 4 + x, y * 2 + 3 * x - 7]
    assert solve_poly_system(eqs, x, y) == [{
        x: Rational(11, 9),
        y: Rational(5, 3)
    }, {
        x: 3,
        y: -1
    }]
    eqs = [y + x**2 - 3, -y + x - 4]
    assert solve_poly_system(eqs, x, y) == [{
        x: Rational(-1, 2) + sqrt(29) / 2,
        y: Rational(-9, 2) + sqrt(29) / 2
    }, {
        x: -sqrt(29) / 2 - Rational(1, 2),
        y: Rational(-9, 2) - sqrt(29) / 2
    }]

    # issue sympy/sympy#6785
    roots = solve_poly_system([((x - 5)**2 / 250000 +
                                (y - Rational(5, 10))**2 / 250000) - 1, x], x,
                              y)
    assert roots == [{
        x: 0,
        y: Rational(1, 2) + 15 * sqrt(1111)
    }, {
        x: 0,
        y: Rational(1, 2) - 15 * sqrt(1111)
    }]

    roots = solve_poly_system([((x - 5)**2 / 250000 +
                                (y - 5.0 / 10)**2 / 250000) - 1, x], x, y)
    assert len(roots) == 2
    assert roots[0][x] == roots[1][x] == 0
    assert roots[0][y].epsilon_eq(-499.474999374969, 1e12)
    assert roots[1][y].epsilon_eq(+500.474999374969, 1e12)