Пример #1
0
def test_MatrixSlice():
    X = MatrixSymbol('X', 4, 4)
    B = MatrixSlice(X, (1, 3), (1, 3))
    C = MatrixSlice(X, (0, 3), (1, 3))
    assert ask(Q.symmetric(B), Q.symmetric(X))
    assert ask(Q.invertible(B), Q.invertible(X))
    assert ask(Q.diagonal(B), Q.diagonal(X))
    assert ask(Q.orthogonal(B), Q.orthogonal(X))
    assert ask(Q.upper_triangular(B), Q.upper_triangular(X))

    assert not ask(Q.symmetric(C), Q.symmetric(X))
    assert not ask(Q.invertible(C), Q.invertible(X))
    assert not ask(Q.diagonal(C), Q.diagonal(X))
    assert not ask(Q.orthogonal(C), Q.orthogonal(X))
    assert not ask(Q.upper_triangular(C), Q.upper_triangular(X))
Пример #2
0
def identify_removable_identity_matrices(expr):
    editor = _EditArrayContraction(expr)

    flag: bool = True
    while flag:
        flag = False
        for arg_with_ind in editor.args_with_ind:
            if isinstance(arg_with_ind.element, Identity):
                k = arg_with_ind.element.shape[0]
                # Candidate for removal:
                if arg_with_ind.indices == [None, None]:
                    # Free identity matrix, will be cleared by _remove_trivial_dims:
                    continue
                elif None in arg_with_ind.indices:
                    ind = [j for j in arg_with_ind.indices if j is not None][0]
                    counted = editor.count_args_with_index(ind)
                    if counted == 1:
                        # Identity matrix contracted only on one index with itself,
                        # transform to a OneArray(k) element:
                        editor.insert_after(arg_with_ind, OneArray(k))
                        editor.args_with_ind.remove(arg_with_ind)
                        flag = True
                        break
                    elif counted > 2:
                        # Case counted = 2 is a matrix multiplication by identity matrix, skip it.
                        # Case counted > 2 is a multiple contraction,
                        # this is a case where the contraction becomes a diagonalization if the
                        # identity matrix is dropped.
                        continue
                elif arg_with_ind.indices[0] == arg_with_ind.indices[1]:
                    ind = arg_with_ind.indices[0]
                    counted = editor.count_args_with_index(ind)
                    if counted > 1:
                        editor.args_with_ind.remove(arg_with_ind)
                        flag = True
                        break
                    else:
                        # This is a trace, skip it as it will be recognized somewhere else:
                        pass
            elif ask(Q.diagonal(arg_with_ind.element)):
                if arg_with_ind.indices == [None, None]:
                    continue
                elif None in arg_with_ind.indices:
                    pass
                elif arg_with_ind.indices[0] == arg_with_ind.indices[1]:
                    ind = arg_with_ind.indices[0]
                    counted = editor.count_args_with_index(ind)
                    if counted == 3:
                        # A_ai B_bi D_ii ==> A_ai D_ij B_bj
                        ind_new = editor.get_new_contraction_index()
                        other_args = [
                            j for j in editor.args_with_ind
                            if j != arg_with_ind
                        ]
                        other_args[1].indices = [
                            ind_new if j == ind else j
                            for j in other_args[1].indices
                        ]
                        arg_with_ind.indices = [ind, ind_new]
                        flag = True
                        break

    return editor.to_array_contraction()
Пример #3
0
def test_diagonal():
    assert ask(Q.diagonal(X + Z.T + Identity(2)),
               Q.diagonal(X) & Q.diagonal(Z)) is True
    assert ask(Q.diagonal(ZeroMatrix(3, 3)))
    assert ask(Q.diagonal(OneMatrix(1, 1))) is True
    assert ask(Q.diagonal(OneMatrix(3, 3))) is False
    assert ask(Q.lower_triangular(X) & Q.upper_triangular(X), Q.diagonal(X))
    assert ask(Q.diagonal(X), Q.lower_triangular(X) & Q.upper_triangular(X))
    assert ask(Q.symmetric(X), Q.diagonal(X))
    assert ask(Q.triangular(X), Q.diagonal(X))
    assert ask(Q.diagonal(C0x0))
    assert ask(Q.diagonal(A1x1))
    assert ask(Q.diagonal(A1x1 + B1x1))
    assert ask(Q.diagonal(A1x1 * B1x1))
    assert ask(Q.diagonal(V1.T * V2))
    assert ask(Q.diagonal(V1.T * (X + Z) * V1))
    assert ask(Q.diagonal(MatrixSlice(Y, (0, 1), (1, 2)))) is True
    assert ask(Q.diagonal(V1.T * (V1 + V2))) is True
    assert ask(Q.diagonal(X**3), Q.diagonal(X))
    assert ask(Q.diagonal(Identity(3)))
    assert ask(Q.diagonal(DiagMatrix(V1)))
    assert ask(Q.diagonal(DiagonalMatrix(X)))
Пример #4
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