qiskit.circuit.library.SGate

class SGate(label=None)

Single qubit S gate (Z**0.5).

It induces a \(\pi/2\) phase, and is sometimes called the P gate (phase).

This is a Clifford gate and a square-root of Pauli-Z.

Matrix Representation:

\[\begin{split}S = \begin{pmatrix} 1 & 0 \\ 0 & i \end{pmatrix}\end{split}\]

Circuit symbol:

     ┌───┐
q_0: ┤ S ├
     └───┘

Equivalent to a \(\pi/2\) radian rotation about the Z axis.

Create new S gate.

__init__(label=None)

Create new S gate.

Methods

__init__([label])	Create new S 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 classical and value val.
control([num_ctrl_qubits, label, ctrl_state])	Return controlled version of gate.
copy([name])	Copy of the instruction.
inverse()	Return inverse of S (SdgGate).
is_parameterized()	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.
reverse_ops()	For a composite instruction, reverse the order of sub-instructions.
to_matrix()	Return a numpy.array for the S gate.
validate_parameter(parameter)	Gate parameters should be int, float, or ParameterExpression

Attributes

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 gate label
params	return instruction params.
unit	Get the time unit of duration.

add_decomposition(decomposition)

Add a decomposition of the instruction to the SessionEquivalenceLibrary.

assemble()

Assemble a QasmQobjInstruction

반환 형식

Instruction

broadcast_arguments(qargs, cargs)

Validation and handling of the arguments and its relationship.

For example, cx([q[0],q[1]], q[2]) means cx(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], ...]
  

매개변수

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

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

반환 형식

Tuple[List, List]

반환값

A tuple with single arguments.

예외

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 classical and value val.

control(num_ctrl_qubits=1, label=None, ctrl_state=None)

Return controlled version of gate. See ControlledGate for usage.

매개변수

• num_ctrl_qubits (Optional[int]) – number of controls to add to gate (default=1)

• label (Optional[str]) – optional gate label

• ctrl_state (Union[int, str, None]) – The control state in decimal or as a bitstring (e.g. ‘111’). If None, use 2**num_ctrl_qubits-1.

반환값

Controlled version of gate. This default algorithm uses num_ctrl_qubits-1 ancillae qubits so returns a gate of size num_qubits + 2*num_ctrl_qubits - 1.

반환 형식

qiskit.circuit.ControlledGate

예외

QiskitError – unrecognized mode or invalid ctrl_state

copy(name=None)

Copy of the instruction.

매개변수

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

반환값

a copy of the current instruction, with the name

updated if it was provided

반환 형식

qiskit.circuit.Instruction

property decompositions

Get the decompositions of the instruction from the SessionEquivalenceLibrary.

property definition

Return definition in terms of other basic gates.

property duration

Get the duration.

inverse()

Return inverse of S (SdgGate).

is_parameterized()

Return True .IFF. instruction is parameterized else False

property label

Return gate label

반환 형식

str

mirror()

DEPRECATED: use instruction.reverse_ops().

반환값

a new instruction with sub-instructions

reversed.

반환 형식

qiskit.circuit.Instruction

property params

return instruction params.

power(exponent)

Creates a unitary gate as gate^exponent.

매개변수

exponent (float) – Gate^exponent

반환값

To which to_matrix is self.to_matrix^exponent.

반환 형식

qiskit.extensions.UnitaryGate

예외

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.

매개변수

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

반환값

Containing the definition.

반환 형식

qiskit.circuit.Instruction

예외

CircuitError – If n < 1.

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.

반환값

a new instruction with

sub-instructions reversed.

반환 형식

qiskit.circuit.Instruction

to_matrix()

Return a numpy.array for the S gate.

property unit

Get the time unit of duration.

validate_parameter(parameter)

Gate parameters should be int, float, or ParameterExpression