qiskit.circuit.library.MCXRecursive¶

class
MCXRecursive
(num_ctrl_qubits=None, label=None, ctrl_state=None)[código fonte]¶ Implement the multicontrolled X gate using recursion.
Using a single ancilla qubit, the multicontrolled X gate is recursively split onto four subregisters. This is done until we reach the 3 or 4controlled X gate since for these we have a concrete implementation that do not require ancillas.
Create new MCX gate.

__init__
(num_ctrl_qubits, label=None, ctrl_state=None)[código fonte]¶ Create new MCX gate.
Methods
__init__
(num_ctrl_qubits[, label, ctrl_state])Create new MCX gate.
add_decomposition
(decomposition)Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble
()Assemble a QasmQobjInstruction
broadcast_arguments
(qargs, cargs)Validation and handling of the arguments and its relationship.
c_if
(classical, val)Add classical condition on register or cbit classical and value val.
control
([num_ctrl_qubits, label, ctrl_state])Return a multicontrolledX gate with more control lines.
copy
([name])Copy of the instruction.
get_num_ancilla_qubits
(num_ctrl_qubits[, mode])Get the number of required ancilla qubits.
inverse
()Invert this gate.
Return True .IFF.
mirror
()DEPRECATED: use instruction.reverse_ops().
power
(exponent)Creates a unitary gate as gate^exponent.
qasm
()Return a default OpenQASM string for the instruction.
repeat
(n)Creates an instruction with gate repeated n amount of times.
For a composite instruction, reverse the order of subinstructions.
soft_compare
(other)Soft comparison between gates.
Return a Numpy.array for the gate unitary matrix.
validate_parameter
(parameter)Gate parameters should be int, float, or ParameterExpression
Attributes
Return the control state of the gate as a decimal integer.
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
Return definition in terms of other basic gates.
Get the duration.
Return instruction label
Get name of gate.
The number of ancilla qubits.
Get number of control qubits.
Get parameters from base_gate.
Get the time unit of duration.

add_decomposition
(decomposition)¶ Add a decomposition of the instruction to the SessionEquivalenceLibrary.

assemble
()¶ Assemble a QasmQobjInstruction

broadcast_arguments
(qargs, cargs)¶ Validation and handling of the arguments and its relationship.
For example,
cx([q[0],q[1]], q[2])
meanscx(q[0], q[2]); cx(q[1], q[2])
. This method yields the arguments in the right grouping. In the given example:in: [[q[0],q[1]], q[2]],[] outs: [q[0], q[2]], [] [q[1], q[2]], []
The general broadcasting rules are:
If len(qargs) == 1:
[q[0], q[1]] > [q[0]],[q[1]]
If len(qargs) == 2:
[[q[0], q[1]], [r[0], r[1]]] > [q[0], r[0]], [q[1], r[1]] [[q[0]], [r[0], r[1]]] > [q[0], r[0]], [q[0], r[1]] [[q[0], q[1]], [r[0]]] > [q[0], r[0]], [q[1], r[0]]
If len(qargs) >= 3:
[q[0], q[1]], [r[0], r[1]], ...] > [q[0], r[0], ...], [q[1], r[1], ...]
 Parâmetros
qargs (
List
) – List of quantum bit arguments.cargs (
List
) – List of classical bit arguments.
 Tipo de retorno
Tuple
[List
,List
] Retorna
A tuple with single arguments.
 Levanta
CircuitError – If the input is not valid. For example, the number of arguments does not match the gate expectation.

c_if
(classical, val)¶ Add classical condition on register or cbit classical and value val.

control
(num_ctrl_qubits=1, label=None, ctrl_state=None)¶ Return a multicontrolledX gate with more control lines.
 Parâmetros
num_ctrl_qubits (int) – number of control qubits.
label (str or None) – An optional label for the gate [Default: None]
ctrl_state (int or str or None) – control state expressed as integer, string (e.g. ‘110’), or None. If None, use all 1s.
 Retorna
controlled version of this gate.
 Tipo de retorno

copy
(name=None)¶ Copy of the instruction.
 Parâmetros
name (str) – name to be given to the copied circuit, if None then the name stays the same.
 Retorna
 a copy of the current instruction, with the name
updated if it was provided
 Tipo de retorno

property
ctrl_state
¶ Return the control state of the gate as a decimal integer.
 Tipo de retorno
int

property
decompositions
¶ Get the decompositions of the instruction from the SessionEquivalenceLibrary.

property
definition
¶ Return definition in terms of other basic gates. If the gate has open controls, as determined from self.ctrl_state, the returned definition is conjugated with X without changing the internal _definition.
 Tipo de retorno
List

property
duration
¶ Get the duration.

static
get_num_ancilla_qubits
(num_ctrl_qubits, mode='recursion')[código fonte]¶ Get the number of required ancilla qubits.

inverse
()[código fonte]¶ Invert this gate. The MCX is its own inverse.

is_parameterized
()¶ Return True .IFF. instruction is parameterized else False

property
label
¶ Return instruction label
 Tipo de retorno
str

mirror
()¶ DEPRECATED: use instruction.reverse_ops().
 Retorna
 a new instruction with subinstructions
reversed.
 Tipo de retorno

property
name
¶ Get name of gate. If the gate has open controls the gate name will become:
<original_name_o<ctrl_state>
where <original_name> is the gate name for the default case of closed control qubits and <ctrl_state> is the integer value of the control state for the gate.
 Tipo de retorno
str

property
num_ancilla_qubits
¶ The number of ancilla qubits.

property
num_ctrl_qubits
¶ Get number of control qubits.
 Retorna
The number of control qubits for the gate.
 Tipo de retorno
int

property
params
¶ Get parameters from base_gate.
 Retorna
List of gate parameters.
 Tipo de retorno
list
 Levanta
CircuitError – Controlled gate does not define a base gate

power
(exponent)¶ Creates a unitary gate as gate^exponent.
 Parâmetros
exponent (float) – Gate^exponent
 Retorna
To which to_matrix is self.to_matrix^exponent.
 Tipo de retorno
 Levanta
CircuitError – If Gate is not unitary

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
(n)¶ Creates an instruction with gate repeated n amount of times.
 Parâmetros
n (int) – Number of times to repeat the instruction
 Retorna
Containing the definition.
 Tipo de retorno
 Levanta
CircuitError – If n < 1.

reverse_ops
()¶ For a composite instruction, reverse the order of subinstructions.
This is done by recursively reversing all subinstructions. It does not invert any gate.
 Retorna
 a new instruction with
subinstructions reversed.
 Tipo de retorno

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.
 Parâmetros
other (instruction) – other instruction.
 Retorna
are self and other equal up to parameter expressions.
 Tipo de retorno
bool

to_matrix
()¶ Return a Numpy.array for the gate unitary matrix.
 Retorna
if the Gate subclass has a matrix definition.
 Tipo de retorno
np.ndarray
 Levanta
CircuitError – If a Gate subclass does not implement this method an exception will be raised when this base class method is called.

property
unit
¶ Get the time unit of duration.

validate_parameter
(parameter)¶ Gate parameters should be int, float, or ParameterExpression
