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QuantumRegister

class qiskit.circuit.QuantumRegister(size=None, name=None, bits=None)

GitHub

Bases: Register

Implement a quantum register.

Create a new generic register.

Either the size or the bits argument must be provided. If size is not None, the register will be pre-populated with bits of the correct type.

Parameters

  • size (int) – Optional. The number of bits to include in the register.
  • name (str) – Optional. The name of the register. If not provided, a unique name will be auto-generated from the register type.
  • bits (list[Bit]) – Optional. A list of Bit() instances to be used to populate the register.

Raises

  • CircuitError – if both the size and bits arguments are provided, or if neither are.
  • CircuitError – if size is not valid.
  • CircuitError – if name is not a valid name according to the OpenQASM spec.
  • CircuitError – if bits contained duplicated bits.
  • CircuitError – if bits contained bits of an incorrect type.

Attributes

instances_counter

Default value: count(6)

name

Get the register name.

name_format

Default value: re.compile('[a-z][a-zA-Z0-9_]*')

prefix

Default value: 'q'

size

Get the register size.


Methods

index

index(bit)

Find the index of the provided bit within this register.

qasm

qasm()

Return OPENQASM string for this register.

Deprecated since version 0.23.0

The method qiskit.circuit.quantumregister.QuantumRegister.qasm() is deprecated as of qiskit-terra 0.23.0. It will be removed no earlier than 3 months after the release date. Correct exporting to OpenQASM 2 is the responsibility of a larger exporter; it cannot safely be done on an object-by-object basis without context. No replacement will be provided, because the premise is wrong.

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