ExactReciprocal

class qiskit.circuit.library.ExactReciprocal(num_state_qubits, scaling, neg_vals=False, name='1/x')

Bases: QuantumCircuit

Exact reciprocal

|x\rangle |0\rangle \mapsto \cos(1/x)|x\rangle|0\rangle + \sin(1/x)|x\rangle |1\rangle

Deprecated since version 2.2

The class qiskit.circuit.library.arithmetic.exact_reciprocal.ExactReciprocal is deprecated as of Qiskit 2.2. It will be removed in Qiskit 3.0. Use the class qiskit.circuit.library.ExactReciprocalGate instead.

Parameters

num_state_qubits (int) – The number of qubits representing the value to invert.
scaling (float) – Scaling factor $s$ of the reciprocal function, i.e. to compute $s / x$ .
neg_vals (bool) – Whether $x$ might represent negative values. In this case the first qubit is the sign, with $|1\rangle$ for negative and $|0\rangle$ for positive. For the negative case it is assumed that the remaining string represents $1 - x$ . This is because $e^{-2 \pi i x} = e^{2 \pi i (1 - x)}$ for $x \in [0,1)$ .
name (str) – The name of the object.

Note

It is assumed that the binary string $x$ represents a number < 1.

Attributes

name

Type: str

A human-readable name for the circuit.

Example

from qiskit import QuantumCircuit

qc = QuantumCircuit(2, 2, name="my_circuit")
print(qc.name)

my_circuit