qiskit/releasenotes/notes/0.20/new-state-preparation-class...

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---
features:
- |
Introduced a new class :class:`~qiskit.circuit.library.StatePreparation`.
This class allows users to prepare a desired state in the same fashion as
:class:`~qiskit.extensions.Initialize` without the reset being
automatically applied.
For example, to prepare a qubit in the state :math:`(|0\rangle - |1\rangle) / \sqrt{2}`::
import numpy as np
from qiskit import QuantumCircuit
circuit = QuantumCircuit(1)
circuit.prepare_state([1/np.sqrt(2), -1/np.sqrt(2)], 0)
circuit.draw()
The output is as::
┌─────────────────────────────────────┐
q_0: ┤ State Preparation(0.70711,-0.70711) ├
└─────────────────────────────────────┘