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Barrier

Barrier(num_qubits) GitHub(opens in a new tab)

Barrier instruction.

Create new barrier instruction.


Attributes

decompositions

Get the decompositions of the instruction from the SessionEquivalenceLibrary.

definition

Return definition in terms of other basic gates.

params

return instruction params.


Methods

add_decomposition

Barrier.add_decomposition(decomposition)

Add a decomposition of the instruction to the SessionEquivalenceLibrary.

assemble

Barrier.assemble()

Assemble a QasmQobjInstruction

broadcast_arguments

Barrier.broadcast_arguments(qargs, cargs)

Validation of the arguments.

Parameters

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

Yields

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

Raises

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

c_if

Barrier.c_if(classical, val)

Add classical condition on register classical and value val.

copy

Barrier.copy(name=None)

Copy of the instruction.

Parameters

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

Returns

a copy of the current instruction, with the name

updated if it was provided

Return type

qiskit.circuit.Instruction

inverse

Barrier.inverse()

Special case. Return self.

is_parameterized

Barrier.is_parameterized()

Return True .IFF. instruction is parameterized else False

mirror

Barrier.mirror()

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

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

Returns

a fresh gate with sub-gates reversed

Return type

qiskit.circuit.Instruction

qasm

Barrier.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];).

repeat

Barrier.repeat(n)

Creates an instruction with gate repeated n amount of times.

Parameters

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

Returns

Containing the definition.

Return type

qiskit.circuit.Instruction

Raises

CircuitError – If n < 1.

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