# Initialize¶

class Initialize(params, num_qubits=None)[source]

Bases: qiskit.circuit.instruction.Instruction

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>.

Methods

 add_decomposition Add a decomposition of the instruction to the SessionEquivalenceLibrary. assemble Assemble a QasmQobjInstruction broadcast_arguments Validation of the arguments. c_if Add classical condition on register or cbit classical and value val. copy 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 Creates an instruction with gate repeated n amount of times. reverse_ops For a composite instruction, reverse the order of sub-instructions. soft_compare Soft comparison between gates. validate_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.

label

Return instruction label

Return type

str

params

return instruction params.

unit

Get the time unit of duration.