iqm.error_reduction_tools.twirling.twirling_modifiers

Module for Poor Man’s Pauli Twirling (PMPT) and circuit manipulation utilities.

This module provides functions and classes for randomizing quantum circuits using PMPT and readout twirling techniques, as well as helpers for circuit analysis and gate manipulation. It is designed to work with Qiskit circuits transpiled to a restricted gate set (typically R and CZ gates), and supports readout twirling, Z rotation tracking, and logical equivalence checks. The main entry point is randomize_circuit, which returns a randomized circuit logically equivalent to the input (considering readout twirling and suppression of Z rotations before measurement).

Functions

absorb_pending_pi_rotation(registers, qubit, ...)	Absorb a pending π rotation (from the left) into the current R gate.
insert_twirling_pi_rotation(registers, ...)	Insert a new π rotation (to the right) after the current R gate for twirling.
process_cz_gate(operation, new_circuit, ...)	Process a CZ gate: propagate pending π-rotation parity as Z kicks.
process_measure_gate(operation, new_circuit, ...)	Process a measurement gate: record readout twirling character and append.
process_r_gate(operation, twirled_circuit, ...)	Process an R gate: absorb pending operations, then optionally insert a twirling π rotation.
randomize_circuit(circuit, rgen[, ...])	Randomize a quantum circuit using Poor Man's Pauli Twirling (PMPT).
take_care_of_pending_operations(registers, ...)	Process pending Z and π-rotation operations before the current R gate.

Classes

TrackingRegisters([virtual_z, extra_phi, ...])

Container for tracking registers during circuit randomization.

Inheritance