qiskit.extensions.Initialize

class Initialize(params, num_qubits=None)

Complex amplitude initialization.

Class that implements the (complex amplitude) initialization of some flexible collection of qubit registers. Note that Initialize is an Instruction and not a Gate since it contains a reset instruction, which is not unitary.

Create new initialize composite.

params (str, list, int or Statevector):

• Statevector: Statevector to initialize to.

• list: vector of complex amplitudes to initialize to.

• string: labels of basis states of the Pauli eigenstates Z, X, Y. See

  from_label(). Notice the order of the labels is reversed with respect to the qubit index to be applied to. Example label ‘01’ initializes the qubit zero to |1> and the qubit one to |0>.

• int: an integer that is used as a bitmap indicating which qubits to initialize

  to |1>. Example: setting params to 5 would initialize qubit 0 and qubit 2 to |1> and qubit 1 to |0>.

num_qubits (int): This parameter is only used if params is an int. Indicates the total

number of qubits in the initialize call. Example: initialize covers 5 qubits and params is 3. This allows qubits 0 and 1 to be initialized to |1> and the remaining 3 qubits to be initialized to |0>.

__init__(params, num_qubits=None)

Create new initialize composite.

params (str, list, int or Statevector):

• Statevector: Statevector to initialize to.

• list: vector of complex amplitudes to initialize to.

• string: labels of basis states of the Pauli eigenstates Z, X, Y. See

  from_label(). Notice the order of the labels is reversed with respect to the qubit index to be applied to. Example label ‘01’ initializes the qubit zero to |1> and the qubit one to |0>.

• int: an integer that is used as a bitmap indicating which qubits to initialize

  to |1>. Example: setting params to 5 would initialize qubit 0 and qubit 2 to |1> and qubit 1 to |0>.

num_qubits (int): This parameter is only used if params is an int. Indicates the total

number of qubits in the initialize call. Example: initialize covers 5 qubits and params is 3. This allows qubits 0 and 1 to be initialized to |1> and the remaining 3 qubits to be initialized to |0>.

Methods

__init__(params[, num_qubits])	Create new initialize composite.
add_decomposition(decomposition)	Add a decomposition of the instruction to the SessionEquivalenceLibrary.
assemble()	Assemble a QasmQobjInstruction
broadcast_arguments(qargs, cargs)	Validation of the arguments.
c_if(classical, val)	Add classical condition on register classical and value val.
copy([name])	Copy of the instruction.
gates_to_uncompute()	Call to create a circuit with gates that take the desired vector to zero.
inverse()	Invert this instruction.
is_parameterized()	Return True .IFF.
mirror()	DEPRECATED: use instruction.reverse_ops().
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.
soft_compare(other)	Soft comparison between gates.
validate_parameter(parameter)	Initialize instruction parameter can be str, int, float, and complex.

Attributes

decompositions	Get the decompositions of the instruction from the SessionEquivalenceLibrary.
definition	Return definition in terms of other basic gates.
duration	Get the duration.
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

broadcast_arguments(qargs, cargs)

Validation of the arguments.

매개변수

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

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

Yields

Tuple(List, List) – 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.

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.

gates_to_uncompute()

Call to create a circuit with gates that take the desired vector to zero.

반환값

circuit to take self.params vector to \(|{00\ldots0}\rangle\)

반환 형식

QuantumCircuit

inverse()

Invert this instruction.

If the instruction is composite (i.e. has a definition), then its definition will be recursively inverted.

Special instructions inheriting from Instruction can implement their own inverse (e.g. T and Tdg, Barrier, etc.)

반환값

a fresh instruction for the inverse

반환 형식

qiskit.circuit.Instruction

예외

CircuitError – if the instruction is not composite and an inverse has not been implemented for it.

is_parameterized()

Return True .IFF. instruction is parameterized else False

mirror()

DEPRECATED: use instruction.reverse_ops().

반환값

a new instruction with sub-instructions

reversed.

반환 형식

qiskit.circuit.Instruction

property params

return instruction params.

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

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

property unit

Get the time unit of duration.

validate_parameter(parameter)

Initialize instruction parameter can be str, int, float, and complex.