AncillaQubit#

class qiskit.circuit.AncillaQubit(register=None, index=None)[source]#

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.

Deprecated since version 0.17: The property qiskit.circuit.bit.Bit.index is deprecated as of qiskit-terra 0.17. It will be removed no earlier than 3 months after the release date. 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.

Deprecated since version 0.17: The property qiskit.circuit.bit.Bit.register is deprecated as of qiskit-terra 0.17. It will be removed no earlier than 3 months after the release date. Instead, use find_bit() to find all the containing registers within a circuit and the index of the bit within the circuit.