MCXGate
class qiskit.circuit.library.MCXGate(num_ctrl_qubits=None, label=None, ctrl_state=None)
Bases: ControlledGate
The general, multi-controlled X gate.
Can be applied to a QuantumCircuit with the mcx() method.
Create new MCX gate.
Attributes
condition_bits
Get Clbits in condition.
ctrl_state
Return the control state of the gate as a decimal integer.
decompositions
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
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.
duration
Get the duration.
label
Return instruction label
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.
num_ancilla_qubits
The number of ancilla qubits.
num_clbits
Return the number of clbits.
num_ctrl_qubits
num_qubits
Return the number of qubits.
params
Get parameters from base_gate.
Returns
List of gate parameters.
Return type
Raises
CircuitError – Controlled gate does not define a base gate
unit
Get the time unit of duration.
Methods
control
control(num_ctrl_qubits=1, label=None, ctrl_state=None)
Return a multi-controlled-X gate with more control lines.
Parameters
- num_ctrl_qubits (int) – number of control qubits.
- label (str or None) – An optional label for the gate [Default: None]
- ctrl_state (int orstr or None) – control state expressed as integer, string (e.g. ‘110’), or None. If None, use all 1s.
Returns
controlled version of this gate.
Return type
get_num_ancilla_qubits
static get_num_ancilla_qubits(num_ctrl_qubits, mode='noancilla')
Get the number of required ancilla qubits without instantiating the class.
This staticmethod might be necessary to check the number of ancillas before creating the gate, or to use the number of ancillas in the initialization.
Return type
inverse
inverse()
Invert this gate. The MCX is its own inverse.