IfElseOp¶

class IfElseOp(condition, true_body, false_body=None, label=None)[source]¶

Bases: ControlFlowOp

A circuit operation which executes a program (true_body) if a provided condition (condition) evaluates to true, and optionally evaluates another program (false_body) otherwise.

Parameters

condition (Tuple[Union[ClassicalRegister, Clbit], int]) -- A condition to be evaluated at circuit runtime which, if true, will trigger the evaluation of true_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.
true_body (QuantumCircuit) -- A program to be executed if condition evaluates to true.
false_body (Optional[QuantumCircuit]) -- A optional program to be executed if condition evaluates to false.
label (Optional[str]) -- An optional label for identifying the instruction.

If provided, false_body must be of the same num_qubits and num_clbits as true_body.

The classical bits used in condition must be a subset of those attached to the circuit on which this IfElseOp will be appended.

Circuit symbol:

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

Create a new instruction.

Parameters

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.

Raises

CircuitError -- when the register is not in the correct format.
TypeError -- when the optional label is provided, but it is not a string.

Methods

`add_decomposition`	Add a decomposition of the instruction to the SessionEquivalenceLibrary.
`assemble`	Assemble a QasmQobjInstruction
`broadcast_arguments`	Validation of the arguments.
`c_if`	Set a classical equality condition on this instruction between the register or cbit `classical` and value `val`.
`copy`	Copy of the instruction.
`inverse`	Invert this instruction.
`is_parameterized`	Return True .IFF.
`qasm`	Return a default OpenQASM string for the instruction.
`repeat`	Creates an instruction with gate repeated n amount of times.
`replace_blocks`	Replace blocks and return new instruction.
`reverse_ops`	For a composite instruction, reverse the order of sub-instructions.
`soft_compare`	Soft comparison between gates.
`validate_parameter`	Instruction parameters has no validation or normalization.

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.