Source code for braket.emulation.passes.circuit_passes.noise_model_transformation

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from braket.circuits import Circuit
from braket.circuits.noise_model import NoiseModel
from braket.emulation.passes import TransformationPass
from braket.program_sets import ProgramSet




class NoiseModelTransformation(TransformationPass):
    """A transformation pass that applies noise models to circuits.

    This pass applies a specified noise model to circuits, adding noise operations
    according to the noise model's criteria. This is essential for realistic device
    emulation that includes noise characteristics.

    Supported specifications:
        - Circuit: Applies noise model to the circuit
        - ProgramSet: Recursively applies noise to all contained circuits

    Examples:
        >>> noise_model = NoiseModel().add_noise(BitFlip(0.1), GateCriteria(Gate.H))
        >>> modifier = NoiseModelModifier(noise_model)
        >>> circuit = Circuit().h(0)
        >>> noisy_circuit = modifier(circuit)
        >>> noisy_circuit = modifier.modify(circuit)
        >>> # Now has bit flip noise after H gate
    """

    def __init__(self, noise_model: NoiseModel):
        """Initialize the noise model modifier.

        Args:
            noise_model (NoiseModel): The noise model to apply to circuits. If None,
                        circuits are returned unchanged.
        """
        self._noise_model = noise_model
        self._supported_specifications = Circuit | ProgramSet



    def transform(self, circuits: Circuit | ProgramSet) -> Circuit | ProgramSet:
        """Apply noise model to circuits.

        Args:
            circuits: Circuit or ProgramSet to add noise to

        Returns:
            Circuit(s) with noise model applied
        """
        if not self._noise_model:
            return circuits
        return self._noise_model.apply(circuits)