Source code for qiskit_aer.library.set_instructions.set_matrix_product_state

# This code is part of Qiskit.
#
# (C) Copyright IBM 2018, 2021.
#
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
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"""
Instruction to set the state simulator state to a matrix.
"""

from qiskit.circuit import QuantumCircuit, Instruction
from ..default_qubits import default_qubits


[docs]class SetMatrixProductState(Instruction): """Set the matrix product state of the simulator""" _directive = True def __init__(self, state): """Create new instruction to set the matrix product state of the simulator. Args: state (Tuple[List[Tuple[np.array[complex_t]]]], List[List[float]]): A matrix_product_state. .. note:: This set instruction must always be performed on the full width of qubits in a circuit. The matrix_product_state consists of a pair of vectors. The first is a vector of pairs of matrices of complex numbers. The second is a vector of vectors of double. """ super().__init__("set_matrix_product_state", len(state[0]), 0, [state])
[docs]def set_matrix_product_state(self, state): """Set the matrix product state of the simulator. Args: state (Tuple[List[Tuple[np.array[complex_t]]]], List[List[float]]): A matrix_product_state. Returns: QuantumCircuit: with attached instruction. Raises: ValueError: If the structure of the state is incorrect .. note: This instruction is always defined across all qubits in a circuit. """ qubits = default_qubits(self) if not isinstance(state, tuple) or len(state) != 2: raise ValueError( "The input matrix product state is not valid. Should be a list of 2 elements" ) if not isinstance(state[0], list) or not isinstance(state[1], list): raise ValueError( "The first element of the input matrix product state is not valid. Should be a list." ) if len(state[0]) != len(state[1]) + 1: raise ValueError( "The input matrix product state is not valid. " "Length of q_reg vector should be 1 more than length of lambda_reg" ) for elem in state[0]: if not isinstance(elem, tuple) or len(elem) != 2: raise ValueError( "The input matrix product state is not valid." "The first element should be a list of length 2" ) return self.append(SetMatrixProductState(state), qubits)
QuantumCircuit.set_matrix_product_state = set_matrix_product_state