Exemple #1
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 def test_bad_input(self):
     """Test bad input."""
     A = numpy.random.randn(3, 3)
     v = numpy.random.randn(2)
     G = givens_matrix_elements(v[0], v[1])
     with self.assertRaises(ValueError):
         double_givens_rotate(A, G, 0, 1, which='a')
Exemple #2
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 def test_odd_dimension(self):
     """Test that it raises an error for odd-dimensional input."""
     A = numpy.random.randn(3, 3)
     v = numpy.random.randn(2)
     G = givens_matrix_elements(v[0], v[1])
     with self.assertRaises(ValueError):
         double_givens_rotate(A, G, 0, 1, which='row')
     with self.assertRaises(ValueError):
         double_givens_rotate(A, G, 0, 1, which='col')
Exemple #3
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    def test_n_equals_9(self):
        n = 9
        # Obtain a random antisymmetric matrix
        rand_mat = numpy.random.randn(2 * n, 2 * n)
        antisymmetric_matrix = rand_mat - rand_mat.T

        # Get the diagonalizing fermionic unitary
        ferm_unitary = diagonalizing_fermionic_unitary(antisymmetric_matrix)
        lower_unitary = ferm_unitary[n:]

        # Get fermionic Gaussian decomposition of lower_unitary
        left_unitary, decomposition, diagonal = (
            fermionic_gaussian_decomposition(lower_unitary))

        # Check that left_unitary zeroes out the correct entries of
        # lower_unitary
        product = left_unitary.dot(lower_unitary)
        for i in range(n - 1):
            for j in range(n - 1 - i):
                self.assertAlmostEqual(product[i, j], 0.)

        # Compute right_unitary
        right_unitary = numpy.eye(2 * n, dtype=complex)
        for parallel_set in decomposition:
            combined_op = numpy.eye(2 * n, dtype=complex)
            for op in parallel_set:
                if op == 'pht':
                    swap_rows(combined_op, n - 1, 2 * n - 1)
                else:
                    i, j, theta, phi = op
                    c = numpy.cos(theta)
                    s = numpy.sin(theta)
                    phase = numpy.exp(1.j * phi)
                    givens_rotation = numpy.array(
                        [[c, -phase * s], [s, phase * c]], dtype=complex)
                    double_givens_rotate(combined_op, givens_rotation, i, j)
            right_unitary = combined_op.dot(right_unitary)

        # Compute left_unitary * lower_unitary * right_unitary^\dagger
        product = left_unitary.dot(lower_unitary.dot(right_unitary.T.conj()))

        # Construct the diagonal matrix
        diag = numpy.zeros((n, 2 * n), dtype=complex)
        diag[range(n), range(n, 2 * n)] = diagonal

        # Assert that W and D are the same
        for i in numpy.ndindex((n, 2 * n)):
            self.assertAlmostEqual(diag[i], product[i])
Exemple #4
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    def test_main_procedure(self):
        for n in self.test_dimensions:
            # Obtain a random quadratic Hamiltonian
            quadratic_hamiltonian = random_quadratic_hamiltonian(n)

            # Get the diagonalizing fermionic unitary
            ferm_unitary = (
                quadratic_hamiltonian.diagonalizing_bogoliubov_transform())
            lower_unitary = ferm_unitary[n:]

            # Get fermionic Gaussian decomposition of lower_unitary
            decomposition, left_decomposition, diagonal, left_diagonal = (
                fermionic_gaussian_decomposition(lower_unitary))

            # Compute left_unitary
            left_unitary = numpy.eye(n, dtype=complex)
            for parallel_set in left_decomposition:
                combined_op = numpy.eye(n, dtype=complex)
                for op in reversed(parallel_set):
                    i, j, theta, phi = op
                    c = numpy.cos(theta)
                    s = numpy.sin(theta)
                    phase = numpy.exp(1.j * phi)
                    givens_rotation = numpy.array(
                        [[c, -phase * s], [s, phase * c]], dtype=complex)
                    givens_rotate(combined_op, givens_rotation, i, j)
                left_unitary = combined_op.dot(left_unitary)
            for i in range(n):
                left_unitary[i] *= left_diagonal[i]
            left_unitary = left_unitary.T
            for i in range(n):
                left_unitary[i] *= diagonal[i]

            # Check that left_unitary zeroes out the correct entries of
            # lower_unitary
            product = left_unitary.dot(lower_unitary)
            for i in range(n - 1):
                for j in range(n - 1 - i):
                    self.assertAlmostEqual(product[i, j], 0.)

            # Compute right_unitary
            right_unitary = numpy.eye(2 * n, dtype=complex)
            for parallel_set in decomposition:
                combined_op = numpy.eye(2 * n, dtype=complex)
                for op in reversed(parallel_set):
                    if op == 'pht':
                        swap_rows(combined_op, n - 1, 2 * n - 1)
                    else:
                        i, j, theta, phi = op
                        c = numpy.cos(theta)
                        s = numpy.sin(theta)
                        phase = numpy.exp(1.j * phi)
                        givens_rotation = numpy.array(
                            [[c, -phase * s], [s, phase * c]], dtype=complex)
                        double_givens_rotate(combined_op, givens_rotation, i,
                                             j)
                right_unitary = combined_op.dot(right_unitary)

            # Compute left_unitary * lower_unitary * right_unitary^\dagger
            product = left_unitary.dot(
                lower_unitary.dot(right_unitary.T.conj()))

            # Construct the diagonal matrix
            diag = numpy.zeros((n, 2 * n), dtype=complex)
            diag[range(n), range(n, 2 * n)] = diagonal

            # Assert that W and D are the same
            for i in numpy.ndindex((n, 2 * n)):
                self.assertAlmostEqual(diag[i], product[i])