Source code for torchquantum.layer.layers.random_layers

"""
MIT License

Copyright (c) 2020-present TorchQuantum Authors

Permission is hereby granted, free of charge, to any person obtaining a copy
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"""

import torch
import torch.nn as nn
import torchquantum as tq
import torchquantum.functional as tqf
import numpy as np

from typing import Iterable
from torchquantum.plugin.qiskit import QISKIT_INCOMPATIBLE_FUNC_NAMES
from torchpack.utils.logging import logger

__all__ = [
    "RandomLayer",
    "RandomLayerAllTypes",
    "RandomOp1All",
]


[docs]class RandomOp1All(tq.QuantumModule):
[docs] def __init__( self, n_wires: int, op_types=(tq.RX, tq.RY, tq.RZ), op_ratios=None, has_params=True, trainable=True, seed=None, ): """Layer adding a random gate to all wires Params: n_wires (int): number of wires/gates in integer format op_types (Iterable): single-wire gates to select from in iterable format op_ratios (Iterable): probabilities to select each gate option in iterable format seed (int): random seed in integer format """ super().__init__() self.n_wires = n_wires self.op_types = op_types self.op_ratios = op_ratios self.seed = seed self.gate_all = nn.ModuleList() if seed is not None: np.random.seed(seed) for k in range(self.n_wires): op = np.random.choice(self.op_types, p=self.op_ratios) self.gate_all.append(op(has_params=has_params, trainable=trainable))
[docs] @tq.static_support def forward(self, q_device: tq.QuantumDevice): for k in range(self.n_wires): self.gate_all[k](q_device, wires=k)
[docs]class RandomLayer(tq.QuantumModule): """ Quantum module that represents a random layer of quantum operations applied to specified wires. Args: wires (int or Iterable[int]): Indices of the wires the operations are applied to. n_ops (int): Number of random operations in the layer. n_params (int): Number of parameters for each random operation. op_ratios (list or float): Ratios determining the relative frequencies of different operation types. op_types (tuple or tq.Operator): Types of random operations to be included in the layer. seed (int): Seed for random number generation. qiskit_compatible (bool): Flag indicating whether the layer should be compatible with Qiskit. Attributes: n_ops (int): Number of random operations in the layer. n_params (int): Number of parameters for each random operation. wires (list): Indices of the wires the operations are applied to. n_wires (int): Number of wires. op_types (list): Types of random operations included in the layer. op_ratios (numpy.array): Ratios determining the relative frequencies of different operation types. seed (int): Seed for random number generation. op_list (tq.QuantumModuleList): List of random operations in the layer. """
[docs] def __init__( self, wires, n_ops=None, n_params=None, op_ratios=None, op_types=(tq.RX, tq.RY, tq.RZ, tq.CNOT), seed=None, qiskit_compatible=False, ): super().__init__() self.n_ops = n_ops self.n_params = n_params assert n_params is not None or n_ops is not None self.wires = wires if isinstance(wires, Iterable) else [wires] self.n_wires = len(wires) op_types = op_types if isinstance(op_types, Iterable) else [op_types] if op_ratios is None: op_ratios = [1] * len(op_types) else: op_ratios = op_ratios if isinstance(op_ratios, Iterable) else [op_ratios] op_types_valid = [] op_ratios_valid = [] if qiskit_compatible: for op_type, op_ratio in zip(op_types, op_ratios): if op_type().name.lower() in QISKIT_INCOMPATIBLE_FUNC_NAMES: logger.warning( f"Remove {op_type} from op_types to make " f"the layer qiskit-compatible." ) else: op_types_valid.append(op_type) op_ratios_valid.append(op_ratio) else: op_types_valid = op_types op_ratios_valid = op_ratios self.op_types = op_types_valid self.op_ratios = np.array(op_ratios_valid) / sum(op_ratios_valid) self.seed = seed self.op_list = tq.QuantumModuleList() if seed is not None: np.random.seed(seed) self.build_random_layer()
[docs] def rebuild_random_layer_from_op_list(self, n_ops_in, wires_in, op_list_in): """ Rebuilds a random layer from the given operation list. This method is used for loading a random layer from a checkpoint. Args: n_ops_in (int): Number of operations in the layer. wires_in (list): Indices of the wires the operations are applied to. op_list_in (list): List of operations in the layer. """ self.n_ops = n_ops_in self.wires = wires_in self.op_list = tq.QuantumModuleList() for op_in in op_list_in: op = tq.op_name_dict[op_in.name.lower()]( has_params=op_in.has_params, trainable=op_in.trainable, wires=op_in.wires, n_wires=op_in.n_wires, ) self.op_list.append(op)
[docs] def build_random_layer(self): op_cnt = 0 param_cnt = 0 while True: op = np.random.choice(self.op_types, p=self.op_ratios) n_op_wires = op.num_wires if n_op_wires > self.n_wires: continue if n_op_wires == -1: is_AnyWire = True n_op_wires = self.n_wires else: is_AnyWire = False op_wires = list( np.random.choice(self.wires, size=n_op_wires, replace=False) ) if is_AnyWire: if op().name in ["MultiRZ"]: operation = op( has_params=True, trainable=True, n_wires=n_op_wires, wires=op_wires, ) else: operation = op(n_wires=n_op_wires, wires=op_wires) elif op().name in tq.operator.parameterized_ops: operation = op(has_params=True, trainable=True, wires=op_wires) else: operation = op(wires=op_wires) self.op_list.append(operation) op_cnt += 1 param_cnt += op.num_params if self.n_ops is not None and op_cnt == self.n_ops: break elif self.n_ops is None and self.n_params is not None: if param_cnt == self.n_params: break elif param_cnt > self.n_params: """ the last operation has too many params and exceed the constraint, so need to remove it and sample another """ op_cnt -= 1 param_cnt -= op.num_params del self.op_list[-1]
[docs] @tq.static_support def forward(self, q_device: tq.QuantumDevice): for op in self.op_list: op(q_device)
[docs]class RandomLayerAllTypes(RandomLayer): """ Random layer with a wide range of quantum gate types. This class extends the `RandomLayer` class to include a variety of quantum gate types as options for the random layer. Args: wires (int or list): Indices of the wires the operations are applied to. n_ops (int): Number of operations in the layer. n_params (int): Number of parameters for each operation. op_ratios (list): Ratios for selecting different types of operations. op_types (tuple): Types of operations to include in the layer. seed (int): Seed for the random number generator. qiskit_compatible (bool): Flag indicating whether the layer should be Qiskit-compatible. """
[docs] def __init__( self, wires, n_ops=None, n_params=None, op_ratios=None, op_types=( tq.Hadamard, tq.SHadamard, tq.PauliX, tq.PauliY, tq.PauliZ, tq.S, tq.T, tq.SX, tq.CNOT, tq.CZ, tq.CY, tq.RX, tq.RY, tq.RZ, tq.RZZ, tq.SWAP, tq.CSWAP, tq.Toffoli, tq.PhaseShift, tq.Rot, tq.MultiRZ, tq.CRX, tq.CRY, tq.CRZ, tq.CRot, tq.U1, tq.U2, tq.U3, tq.MultiCNOT, tq.MultiXCNOT, ), seed=None, qiskit_compatible=False, ): super().__init__( wires=wires, n_ops=n_ops, n_params=n_params, op_ratios=op_ratios, op_types=op_types, seed=seed, qiskit_compatible=qiskit_compatible, )