def apply_observables()

in src/braket/default_simulator/density_matrix_simulation.py [0:0]

• 12 lines of code
• 3 McCabe index (conditional complexity)

    def apply_observables(self, observables: List[Observable]) -> None:
        """Applies the diagonalizing matrices of the given observables
        to the state of the simulation.

        This method can only be called once.

        Args:
            observables (List[Observable]): The observables to apply

        Raises:
            RuntimeError: If this method is called more than once
        """
        if self._post_observables is not None:
            raise RuntimeError("Observables have already been applied.")
        operations = list(
            sum(
                [observable.diagonalizing_gates(self._qubit_count) for observable in observables],
                (),
            )
        )
        self._post_observables = DensityMatrixSimulation._apply_operations(
            self._density_matrix, self._qubit_count, operations
        )