qiskit.circuit.library.CHGate¶

class
CHGate
(label=None, ctrl_state=None)[소스]¶ ControlledHadamard gate.
Applies a Hadamard on the target qubit if the control is in the \(1\rangle\) state.
Circuit symbol:
 q_0: ──■──
┌─┴─┐
 q_1: ┤ H ├
└───┘
Matrix Representation:
\[\begin{split}CH\ q_0, q_1 = I \otimes 0\rangle\langle 0 + H \otimes 1\rangle\langle 1 = \begin{pmatrix} 1 & 0 & 0 & 0 \\ 0 & \frac{1}{\sqrt{2}} & 0 & \frac{1}{\sqrt{2}} \\ 0 & 0 & 1 & 0 \\ 0 & \frac{1}{\sqrt{2}} & 0 & \frac{1}{\sqrt{2}} \end{pmatrix}\end{split}\]참고
In Qiskit’s convention, higher qubit indices are more significant (little endian convention). In many textbooks, controlled gates are presented with the assumption of more significant qubits as control, which in our case would be q_1. Thus a textbook matrix for this gate will be:
┌───┐ q_0: ┤ H ├ └─┬─┘ q_1: ──■──
\[\begin{split}CH\ q_1, q_0 = 0\rangle\langle 0 \otimes I + 1\rangle\langle 1 \otimes H = \begin{pmatrix} 1 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 \\ 0 & 0 & \frac{1}{\sqrt{2}} & \frac{1}{\sqrt{2}} \\ 0 & 0 & \frac{1}{\sqrt{2}} & \frac{1}{\sqrt{2}} \end{pmatrix}\end{split}\]Create new CH gate.
Methods
__init__
([label, ctrl_state])Create new CH 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 inverted CH gate (itself).
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 gate label
Get name of gate.
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
 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])
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], ...]
 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 labelctrl_state (
Union
[int
,str
,None
]) – The control state in decimal or as a bitstring (e.g. ‘111’). If None, use 2**num_ctrl_qubits1.
 반환값
Controlled version of gate. This default algorithm uses num_ctrl_qubits1 ancillae qubits so returns a gate of size num_qubits + 2*num_ctrl_qubits  1.
 반환 형식
 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

property
ctrl_state
¶ Return the control state of the gate as a decimal integer.
 반환 형식
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.
 반환 형식
List

property
duration
¶ Get the duration.

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 subinstructions
reversed.
 반환 형식

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.
 반환 형식
str

property
num_ctrl_qubits
¶ Get number of control qubits.
 반환값
The number of control qubits for the gate.
 반환 형식
int

property
params
¶ Get parameters from base_gate.
 반환값
List of gate parameters.
 반환 형식
list
 예외
CircuitError – Controlled gate does not define a base gate

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
 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
 예외
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.
 반환값
 a new instruction with
subinstructions reversed.
 반환 형식

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.
 매개변수
other (instruction) – other instruction.
 반환값
are self and other equal up to parameter expressions.
 반환 형식
bool

to_matrix
()¶ Return a Numpy.array for the gate unitary matrix.
 반환값
if the Gate subclass has a matrix definition.
 반환 형식
np.ndarray
 예외
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