WhileLoopOp#

class qiskit.circuit.WhileLoopOp(condition, body, label=None)[fuente]#

Bases: ControlFlowOp

A circuit operation which repeatedly executes a subcircuit (body) until a condition (condition) evaluates as False.

Parámetros:
  • condition (tuple[ClassicalRegister, int] | tuple[Clbit, int] | expr.Expr) – A condition to be checked prior to executing body. Can be specified as either a tuple of a ClassicalRegister to be tested for equality with a given int, or as a tuple of a Clbit to be compared to either a bool or an int.

  • body (QuantumCircuit) – The loop body to be repeatedly executed.

  • label (str | None) – An optional label for identifying the instruction.

The classical bits used in condition must be a subset of those attached to body.

Circuit symbol:

     ┌─────────────┐
q_0: ┤0            ├
     │             │
q_1: ┤1            ├
     │  while_loop │
q_2: ┤2            ├
     │             │
c_0: ╡0            ╞
     └─────────────┘

Create a new instruction.

Parámetros:
  • name (str) – instruction name

  • num_qubits (int) – instruction’s qubit width

  • num_clbits (int) – instruction’s clbit width

  • params (list[int|float|complex|str|ndarray|list|ParameterExpression]) – list of parameters

  • duration (int or float) – instruction’s duration. it must be integer if unit is “dt”

  • unit (str) – time unit of duration

  • label (str or None) – An optional label for identifying the instruction.

Muestra:
  • CircuitError – when the register is not in the correct format.

  • TypeError – when the optional label is provided, but it is not a string.

Attributes

blocks#
condition_bits#

Get Clbits in condition.

decompositions#

Get the decompositions of the instruction from the SessionEquivalenceLibrary.

definition#

Return definition in terms of other basic gates.

duration#

Get the duration.

label#

Return instruction label

name#

Return the name.

num_clbits#

Return the number of clbits.

num_qubits#

Return the number of qubits.

params#
unit#

Get the time unit of duration.

Methods

add_decomposition(decomposition)#

Add a decomposition of the instruction to the SessionEquivalenceLibrary.

assemble()#

Assemble a QasmQobjInstruction

broadcast_arguments(qargs, cargs)#

Validation of the arguments.

Parámetros:
  • qargs (List) – List of quantum bit arguments.

  • cargs (List) – List of classical bit arguments.

Campos:

Tuple(List, List) – A tuple with single arguments.

Muestra:

CircuitError – If the input is not valid. For example, the number of arguments does not match the gate expectation.

c_if(classical, val)[fuente]#

Set a classical equality condition on this instruction between the register or cbit classical and value val.

Nota

This is a setter method, not an additive one. Calling this multiple times will silently override any previously set condition; it does not stack.

copy(name=None)#

Copy of the instruction.

Parámetros:

name (str) – name to be given to the copied circuit, if None then the name stays the same.

Devuelve:

a copy of the current instruction, with the name updated if it was provided

Tipo del valor devuelto:

qiskit.circuit.Instruction

inverse()#

Invert this instruction.

If the instruction is composite (i.e. has a definition), then its definition will be recursively inverted.

Special instructions inheriting from Instruction can implement their own inverse (e.g. T and Tdg, Barrier, etc.)

Devuelve:

a fresh instruction for the inverse

Tipo del valor devuelto:

qiskit.circuit.Instruction

Muestra:

CircuitError – if the instruction is not composite and an inverse has not been implemented for it.

is_parameterized()#

Return True .IFF. instruction is parameterized else False

qasm()#

Return a default OpenQASM string for the instruction.

Derived instructions may override this to print in a different format (e.g. measure q[0] -> c[0];).

Obsoleto desde la versión 0.25.0: The method qiskit.circuit.instruction.Instruction.qasm() is deprecated as of qiskit-terra 0.25.0. 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.

repeat(n)#

Creates an instruction with gate repeated n amount of times.

Parámetros:

n (int) – Number of times to repeat the instruction

Devuelve:

Containing the definition.

Tipo del valor devuelto:

qiskit.circuit.Instruction

Muestra:

CircuitError – If n < 1.

replace_blocks(blocks)[fuente]#

Replace blocks and return new instruction. :param blocks: Tuple of QuantumCircuits to replace in instruction.

Devuelve:

New ControlFlowOp with replaced blocks.

reverse_ops()#

For a composite instruction, reverse the order of sub-instructions.

This is done by recursively reversing all sub-instructions. It does not invert any gate.

Devuelve:

a new instruction with

sub-instructions reversed.

Tipo del valor devuelto:

qiskit.circuit.Instruction

soft_compare(other)#

Soft comparison between gates. Their names, number of qubits, and classical bit numbers must match. The number of parameters must match. Each parameter is compared. If one is a ParameterExpression then it is not taken into account.

Parámetros:

other (instruction) – other instruction.

Devuelve:

are self and other equal up to parameter expressions.

Tipo del valor devuelto:

bool

validate_parameter(parameter)#

Instruction parameters has no validation or normalization.