Skip to main contentIBM Quantum Documentation
You are viewing the API reference for an old version of Qiskit SDK. Switch to latest version

Clbit

class qiskit.circuit.Clbit(register=None, index=None)

GitHub(opens in a new tab)

Bases: Bit

Implement a classical bit.

Creates a classical bit.

Parameters

Raises

CircuitError – if the provided register is not a valid ClassicalRegister


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.

Was this page helpful?
Report a bug or request content on GitHub.