Example #1
0
def test_triangular():
    assert ask(Q.upper_triangular(X + Z.T + Identity(2)),
               Q.upper_triangular(X) & Q.lower_triangular(Z)) is True
    assert ask(Q.upper_triangular(X * Z.T),
               Q.upper_triangular(X) & Q.lower_triangular(Z)) is True
    assert ask(Q.lower_triangular(Identity(3))) is True
    assert ask(Q.lower_triangular(ZeroMatrix(3, 3))) is True
    assert ask(Q.upper_triangular(ZeroMatrix(3, 3))) is True
    assert ask(Q.lower_triangular(OneMatrix(1, 1))) is True
    assert ask(Q.upper_triangular(OneMatrix(1, 1))) is True
    assert ask(Q.lower_triangular(OneMatrix(3, 3))) is False
    assert ask(Q.upper_triangular(OneMatrix(3, 3))) is False
    assert ask(Q.triangular(X), Q.unit_triangular(X))
    assert ask(Q.upper_triangular(X**3), Q.upper_triangular(X))
    assert ask(Q.lower_triangular(X**3), Q.lower_triangular(X))
Example #2
0
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
Example #3
0
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
Example #4
0
def test_refine():
    assert refine(det(A), Q.orthogonal(A)) == 1
    assert refine(det(A), Q.singular(A)) == 0
    assert refine(det(A), Q.unit_triangular(A)) == 1
    assert refine(det(A), Q.normal(A)) == det(A)
Example #5
0
def get_known_facts(x=None):
    """
    Facts between unary predicates.

    Parameters
    ==========

    x : Symbol, optional
        Placeholder symbol for unary facts. Default is ``Symbol('x')``.

    Returns
    =======

    fact : Known facts in conjugated normal form.

    """
    if x is None:
        x = Symbol('x')

    fact = And(
        # primitive predicates for extended real exclude each other.
        Exclusive(Q.negative_infinite(x), Q.negative(x), Q.zero(x),
                  Q.positive(x), Q.positive_infinite(x)),

        # build complex plane
        Exclusive(Q.real(x), Q.imaginary(x)),
        Implies(Q.real(x) | Q.imaginary(x), Q.complex(x)),

        # other subsets of complex
        Exclusive(Q.transcendental(x), Q.algebraic(x)),
        Equivalent(Q.real(x),
                   Q.rational(x) | Q.irrational(x)),
        Exclusive(Q.irrational(x), Q.rational(x)),
        Implies(Q.rational(x), Q.algebraic(x)),

        # integers
        Exclusive(Q.even(x), Q.odd(x)),
        Implies(Q.integer(x), Q.rational(x)),
        Implies(Q.zero(x), Q.even(x)),
        Exclusive(Q.composite(x), Q.prime(x)),
        Implies(Q.composite(x) | Q.prime(x),
                Q.integer(x) & Q.positive(x)),
        Implies(Q.even(x) & Q.positive(x) & ~Q.prime(x), Q.composite(x)),

        # hermitian and antihermitian
        Implies(Q.real(x), Q.hermitian(x)),
        Implies(Q.imaginary(x), Q.antihermitian(x)),
        Implies(Q.zero(x),
                Q.hermitian(x) | Q.antihermitian(x)),

        # define finity and infinity, and build extended real line
        Exclusive(Q.infinite(x), Q.finite(x)),
        Implies(Q.complex(x), Q.finite(x)),
        Implies(
            Q.negative_infinite(x) | Q.positive_infinite(x), Q.infinite(x)),

        # commutativity
        Implies(Q.finite(x) | Q.infinite(x), Q.commutative(x)),

        # matrices
        Implies(Q.orthogonal(x), Q.positive_definite(x)),
        Implies(Q.orthogonal(x), Q.unitary(x)),
        Implies(Q.unitary(x) & Q.real_elements(x), Q.orthogonal(x)),
        Implies(Q.unitary(x), Q.normal(x)),
        Implies(Q.unitary(x), Q.invertible(x)),
        Implies(Q.normal(x), Q.square(x)),
        Implies(Q.diagonal(x), Q.normal(x)),
        Implies(Q.positive_definite(x), Q.invertible(x)),
        Implies(Q.diagonal(x), Q.upper_triangular(x)),
        Implies(Q.diagonal(x), Q.lower_triangular(x)),
        Implies(Q.lower_triangular(x), Q.triangular(x)),
        Implies(Q.upper_triangular(x), Q.triangular(x)),
        Implies(Q.triangular(x),
                Q.upper_triangular(x) | Q.lower_triangular(x)),
        Implies(Q.upper_triangular(x) & Q.lower_triangular(x), Q.diagonal(x)),
        Implies(Q.diagonal(x), Q.symmetric(x)),
        Implies(Q.unit_triangular(x), Q.triangular(x)),
        Implies(Q.invertible(x), Q.fullrank(x)),
        Implies(Q.invertible(x), Q.square(x)),
        Implies(Q.symmetric(x), Q.square(x)),
        Implies(Q.fullrank(x) & Q.square(x), Q.invertible(x)),
        Equivalent(Q.invertible(x), ~Q.singular(x)),
        Implies(Q.integer_elements(x), Q.real_elements(x)),
        Implies(Q.real_elements(x), Q.complex_elements(x)),
    )
    return fact