AncillaQubit
class qiskit.circuit.AncillaQubit(register=None, index=None)
Bases: Qubit
A qubit used as ancillary qubit.
Creates a qubit.
Parameters
- register (QuantumRegister) – Optional. A quantum register containing the bit.
- index (int) – Optional. The index of the bit in its containing register.
Raises
CircuitError – if the provided register is not a valid QuantumRegister
Attributes
index
Get the index of an old-style bit in the register that owns it.
In modern Qiskit Terra (version 0.17+), bits are the fundamental object and registers are aliases to collections of bits. A bit can be in many registers depending on the circuit, so a single containing register is no longer a property of a bit. It is an error to access this attribute on bits that were not constructed as “owned” by a register.
The property qiskit.circuit.bit.Bit.index is deprecated as of qiskit-terra 0.17. It will be removed in the Qiskit 1.0 release. Instead, use find_bit() to find all the containing registers within a circuit and the index of the bit within the circuit.
register
Get the register of an old-style bit.
In modern Qiskit Terra (version 0.17+), bits are the fundamental object and registers are aliases to collections of bits. A bit can be in many registers depending on the circuit, so a single containing register is no longer a property of a bit. It is an error to access this attribute on bits that were not constructed as “owned” by a register.
The property qiskit.circuit.bit.Bit.register is deprecated as of qiskit-terra 0.17. It will be removed in the Qiskit 1.0 release. Instead, use find_bit() to find all the containing registers within a circuit and the index of the bit within the circuit.