Python ask.Q类代码示例

def refine_MatMul(expr, assumptions):
    """
    >>> from sympy import MatrixSymbol, Q, assuming, refine
    >>> X = MatrixSymbol('X', 2, 2)
    >>> expr = X * X.T
    >>> print(expr)
    X*X.T
    >>> with assuming(Q.orthogonal(X)):
    ...     print(refine(expr))
    I
    """
    newargs = []
    exprargs = []

    for args in expr.args:
        if args.is_Matrix:
            exprargs.append(args)
        else:
            newargs.append(args)

    last = exprargs[0]
    for arg in exprargs[1:]:
        if arg == last.T and ask(Q.orthogonal(arg), assumptions):
            last = Identity(arg.shape[0])
        elif arg == last.conjugate() and ask(Q.unitary(arg), assumptions):
            last = Identity(arg.shape[0])
        else:
            newargs.append(last)
            last = arg
    newargs.append(last)

    return MatMul(*newargs)

def test_is_literal():
    assert is_literal(True) is True
    assert is_literal(False) is True
    assert is_literal(A) is True
    assert is_literal(~A) is True
    assert is_literal(Or(A, B)) is False
    assert is_literal(Q.zero(A)) is True
    assert is_literal(Not(Q.zero(A))) is True
    assert is_literal(Or(A, B)) is False
    assert is_literal(And(Q.zero(A), Q.zero(B))) is False

def test_global():
    """Test for global assumptions"""
    global_assumptions.add(Q.is_true(x > 0))
    assert Q.is_true(x > 0) in global_assumptions
    global_assumptions.remove(Q.is_true(x > 0))
    assert not Q.is_true(x > 0) in global_assumptions
    # same with multiple of assumptions
    global_assumptions.add(Q.is_true(x > 0), Q.is_true(y > 0))
    assert Q.is_true(x > 0) in global_assumptions
    assert Q.is_true(y > 0) in global_assumptions
    global_assumptions.clear()
    assert not Q.is_true(x > 0) in global_assumptions
    assert not Q.is_true(y > 0) in global_assumptions

def test_binary_symbols():
    assert ITE(x < 1, y, z).binary_symbols == set((y, z))
    for f in (Eq, Ne):
        assert f(x, 1).binary_symbols == set()
        assert f(x, True).binary_symbols == set([x])
        assert f(x, False).binary_symbols == set([x])
    assert S.true.binary_symbols == set()
    assert S.false.binary_symbols == set()
    assert x.binary_symbols == set([x])
    assert And(x, Eq(y, False), Eq(z, 1)).binary_symbols == set([x, y])
    assert Q.prime(x).binary_symbols == set()
    assert Q.is_true(x < 1).binary_symbols == set()
    assert Q.is_true(x).binary_symbols == set([x])
    assert Q.is_true(Eq(x, True)).binary_symbols == set([x])
    assert Q.prime(x).binary_symbols == set()

def refine_Inverse(expr, assumptions):
    """
    >>> from sympy import MatrixSymbol, Q, assuming, refine
    >>> X = MatrixSymbol('X', 2, 2)
    >>> X.I
    X**(-1)
    >>> with assuming(Q.orthogonal(X)):
    ...     print(refine(X.I))
    X.T
    """
    if ask(Q.orthogonal(expr), assumptions):
        return expr.arg.T
    elif ask(Q.unitary(expr), assumptions):
        return expr.arg.conjugate()
    elif ask(Q.singular(expr), assumptions):
        raise ValueError("Inverse of singular matrix %s" % expr.arg)

    return expr

def refine_Determinant(expr, assumptions):
    """
    >>> from sympy import MatrixSymbol, Q, assuming, refine, det
    >>> X = MatrixSymbol('X', 2, 2)
    >>> det(X)
    Determinant(X)
    >>> with assuming(Q.orthogonal(X)):
    ...     print(refine(det(X)))
    1
    """
    if ask(Q.orthogonal(expr.arg), assumptions):
        return S.One
    elif ask(Q.singular(expr.arg), assumptions):
        return S.Zero
    elif ask(Q.unit_triangular(expr.arg), assumptions):
        return S.One

    return expr

def refine_Transpose(expr, assumptions):
    """
    >>> from sympy import MatrixSymbol, Q, assuming, refine
    >>> X = MatrixSymbol('X', 2, 2)
    >>> X.T
    X.T
    >>> with assuming(Q.symmetric(X)):
    ...     print(refine(X.T))
    X
    """
    if ask(Q.symmetric(expr), assumptions):
        return expr.arg

    return expr

    def _contains(self, other):
        from sympy.assumptions.ask import ask, Q
        if ask(Q.real(other)) is False:
            return False

        if self.left_open:
            expr = other > self.start
        else:
            expr = other >= self.start

        if self.right_open:
            expr = And(expr, other < self.end)
        else:
            expr = And(expr, other <= self.end)

        return expr

 def _contains(self, other):
     from sympy.assumptions.ask import ask, Q
     return (other >= self.inf and other <= self.sup and
             ask(Q.integer((self.start - other)/self.step)))

def register_fact(klass, fact, registry=fact_registry):
    registry[klass] |= set([fact])


for klass, fact in [
    (Mul, Equivalent(Q.zero, AnyArgs(Q.zero))),
    (MatMul, Implies(AllArgs(Q.square), Equivalent(Q.invertible, AllArgs(Q.invertible)))),
    (Add, Implies(AllArgs(Q.positive), Q.positive)),
    (Add, Implies(AllArgs(Q.negative), Q.negative)),
    (Mul, Implies(AllArgs(Q.positive), Q.positive)),
    (Mul, Implies(AllArgs(Q.commutative), Q.commutative)),
    (Mul, Implies(AllArgs(Q.real), Q.commutative)),
    # This one can still be made easier to read. I think we need basic pattern
    # matching, so that we can just write Equivalent(Q.zero(x**y), Q.zero(x) & Q.positive(y))
    (Pow, CustomLambda(lambda power: Equivalent(Q.zero(power), Q.zero(power.base) & Q.positive(power.exp)))),
    (Integer, CheckIsPrime(Q.prime)),
    # Implicitly assumes Mul has more than one arg
    # Would be AllArgs(Q.prime | Q.composite) except 1 is composite
    (Mul, Implies(AllArgs(Q.prime), ~Q.prime)),
    # More advanced prime assumptions will require inequalities, as 1 provides
    # a corner case.
    (Mul, Implies(AllArgs(Q.imaginary | Q.real), Implies(ExactlyOneArg(Q.imaginary), Q.imaginary))),
    (Mul, Implies(AllArgs(Q.real), Q.real)),
    (Add, Implies(AllArgs(Q.real), Q.real)),
    #General Case: Odd number of imaginary args implies mul is imaginary(To be implemented)
    (Mul, Implies(AllArgs(Q.real), Implies(ExactlyOneArg(Q.irrational),
        Q.irrational))),
    (Add, Implies(AllArgs(Q.real), Implies(ExactlyOneArg(Q.irrational),
        Q.irrational))),
    (Mul, Implies(AllArgs(Q.rational), Q.rational)),

def test_equal():
    """Test for equality"""
    assert Q.positive(x)  == Q.positive(x)
    assert Q.positive(x)  != ~Q.positive(x)
    assert ~Q.positive(x) == ~Q.positive(x)

def test_composite_predicates():
    pred = Q.integer | ~Q.positive
    assert type(pred(x)) is Or
    assert pred(x) == Q.integer(x) | ~Q.positive(x)

def test_equal():
    """Test for equality"""
    x = symbols('x')
    assert Q.positive(x)  == Q.positive(x)
    assert Q.positive(x)  != ~Q.positive(x)
    assert ~Q.positive(x) == ~Q.positive(x)

def test_pretty():
    x = symbols('x')
    assert pretty(Q.positive(x)) == "Q.positive(x)"

def test_pretty():
    assert pretty(Q.positive(x)) == "Q.positive(x)"