# qiskit.circuit.library.YGate¶

class YGate(label=None)[ソース]

The single-qubit Pauli-Y gate ($$\sigma_y$$).

Matrix Representation:

$\begin{split}Y = \begin{pmatrix} 0 & -i \\ i & 0 \end{pmatrix}\end{split}$

Circuit symbol:

     ┌───┐
q_0: ┤ Y ├
└───┘


Equivalent to a $$\pi$$ radian rotation about the Y axis.

A global phase difference exists between the definitions of $$RY(\pi)$$ and $$Y$$.

$\begin{split}RY(\pi) = \begin{pmatrix} 0 & -1 \\ 1 & 0 \end{pmatrix} = -i Y\end{split}$

The gate is equivalent to a bit and phase flip.

$\begin{split}|0\rangle \rightarrow i|1\rangle \\ |1\rangle \rightarrow -i|0\rangle\end{split}$

Create new Y gate.

__init__(label=None)[ソース]

Create new Y gate.

Methods

 __init__([label]) Create new Y gate. add_decomposition(decomposition) Add a decomposition of the instruction to the SessionEquivalenceLibrary. 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 a (multi-)controlled-Y gate. copy([name]) Copy of the instruction. Return inverted Y gate ($$Y{\dagger} = Y$$) Return True .IFF. DEPRECATED: use instruction.reverse_ops(). power(exponent) Creates a unitary gate as gate^exponent. Return a default OpenQASM string for the instruction. Creates an instruction with gate repeated n amount of times. For a composite instruction, reverse the order of sub-instructions. 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

 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

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]], []


• 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], ...]

パラメータ
• qargs (List) – List of quantum bit arguments.

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

Tuple[List, List]

A tuple with single arguments.

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)[ソース]

Return a (multi-)controlled-Y gate.

One control returns a CY gate.

パラメータ
• 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.

controlled version of this gate.

ControlledGate

copy(name=None)

Copy of the instruction.

パラメータ

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

a copy of the current instruction, with the name

updated if it was provided

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()[ソース]

Return inverted Y gate ($$Y{\dagger} = Y$$)

is_parameterized()

Return True .IFF. instruction is parameterized else False

property label

Return gate label

str

mirror()

DEPRECATED: use instruction.reverse_ops().

a new instruction with sub-instructions

reversed.

qiskit.circuit.Instruction

property params

return instruction params.

power(exponent)

Creates a unitary gate as gate^exponent.

パラメータ

exponent (float) – Gate^exponent

To which to_matrix is self.to_matrix^exponent.

qiskit.extensions.UnitaryGate

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.

パラメータ

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

Containing the definition.

qiskit.circuit.Instruction

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.

a new instruction with

sub-instructions reversed.

qiskit.circuit.Instruction

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.

パラメータ

other (instruction) – other instruction.

are self and other equal up to parameter expressions.

bool

to_matrix()

Return a Numpy.array for the gate unitary matrix.

if the Gate subclass has a matrix definition.

np.ndarray

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