Problemas del Modelo de Retícula con v0.5#

Los modelos de retícula solo han recibido algunas actualizaciones menores en esta versión de Qiskit Nature.

Un cambio importante es que, dado que todos los modelos de retícula ahora implementan la nueva interfaz Hamiltonian en lugar de la anterior Property, obtienes el operador real a través del método second_q_op() en lugar de second_q_ops() (Observa la s al final).

Descripción General#

En particular, las importaciones han cambiado de la siguiente manera:

Ubicación antigua

Ubicación nueva

qiskit_nature.problems.second_quantization.lattice.models

qiskit_nature.second_q.hamiltonians

qiskit_nature.problems.second_quantization.lattice.lattices

qiskit_nature.second_q.hamiltonians.lattices

qiskit_nature.problems.second_quantization.lattice.LatticeModelProblem

qiskit_nature.second_q.problems.LatticeModelProblem

Además, los métodos de fábrica para los objetos Lattice definidos en las clases LatticeModel se migraron de la siguiente manera:

Método anterior

Nuevo método

FermiHubbardModel.uniform_parameters

Lattice.uniform_parameters

FermiHubbardModel.from_parameters

Lattice.from_adjacency_matrix

IsingModel.uniform_parameters

Lattice.uniform_parameters

IsingModel.from_parameters

Lattice.from_adjacency_matrix

Más Recursos#

Asegúrate de consultar los siguientes tutoriales sobre cómo usar el nuevo código:

FermiHubbardModel.uniform_parameters#

Previamente#

from qiskit_nature.problems.second_quantization.lattice.lattices import LineLattice
from qiskit_nature.problems.second_quantization.lattice.models import FermiHubbardModel

line = LineLattice(2)
fermi = FermiHubbardModel.uniform_parameters(line, 2.0, 4.0, 3.0)
print(fermi.second_q_ops())  # Note: the trailing `s`

Fermionic Operator
register length=4, number terms=10
  (2+0j) * ( +_0 -_2 )
+ (-2+0j) * ( -_0 +_2 )
+ (4+0j) * ( +_0 -_0 )
+ (4+0j) * ( +_2 -_2 )
+ (2+0j) * ( +_1 -_3 )
+ (-2+0j) * ( -_1 +_3 )
+ (4+0j) * ( +_1 -_1 )
+ (4+0j) * ( +_3 -_3 )
+ (3+0j) * ...

Nuevo#

from qiskit_nature.second_q.hamiltonians.lattices import LineLattice
from qiskit_nature.second_q.hamiltonians import FermiHubbardModel

line = LineLattice(2)
fermi = FermiHubbardModel(line.uniform_parameters(2.0, 4.0), 3.0)
print(fermi.second_q_op())  # Note: NO trailing `s`

Fermionic Operator
number spin orbitals=4, number terms=10
  2.0 * ( +_0 -_2 )
+ -2.0 * ( -_0 +_2 )
+ 4.0 * ( +_0 -_0 )
+ 4.0 * ( +_2 -_2 )
+ 2.0 * ( +_1 -_3 )
+ -2.0 * ( -_1 +_3 )
+ 4.0 * ( +_1 -_1 )
+ 4.0 * ( +_3 -_3 )
+ 3.0 * ( +_0 -_0 +_1 -_1 )
+ 3.0 * ( +_2 -_2 +_3 -_3 )

FermiHubbardModel.from_parameters#

Previamente#

import numpy as np
from qiskit_nature.problems.second_quantization.lattice.models import FermiHubbardModel

interaction = np.array([[4.0, 2.0], [2.0, 4.0]])

fermi = FermiHubbardModel.from_parameters(interaction, 3.0)
print(fermi.second_q_ops())  # Note: the trailing `s`

Fermionic Operator
register length=4, number terms=10
  (4+0j) * ( +_0 -_0 )
+ (2+0j) * ( +_0 -_2 )
+ (-2+0j) * ( -_0 +_2 )
+ (4+0j) * ( +_2 -_2 )
+ (4+0j) * ( +_1 -_1 )
+ (2+0j) * ( +_1 -_3 )
+ (-2+0j) * ( -_1 +_3 )
+ (4+0j) * ( +_3 -_3 )
+ (3+0j) * ...

Nuevo#

import numpy as np
from qiskit_nature.second_q.hamiltonians.lattices import Lattice
from qiskit_nature.second_q.hamiltonians import FermiHubbardModel

interaction = np.array([[4.0, 2.0], [2.0, 4.0]])

lattice = Lattice.from_adjacency_matrix(interaction)
fermi = FermiHubbardModel(lattice, 3.0)
print(fermi.second_q_op())  # Note: NO trailing `s`

Fermionic Operator
number spin orbitals=4, number terms=10
  4.0 * ( +_0 -_0 )
+ 2.0 * ( +_0 -_2 )
+ -2.0 * ( -_0 +_2 )
+ 4.0 * ( +_2 -_2 )
+ 4.0 * ( +_1 -_1 )
+ 2.0 * ( +_1 -_3 )
+ -2.0 * ( -_1 +_3 )
+ 4.0 * ( +_3 -_3 )
+ 3.0 * ( +_0 -_0 +_1 -_1 )
+ 3.0 * ( +_2 -_2 +_3 -_3 )

IsingModel.uniform_parameters#

Previamente#

from qiskit_nature.problems.second_quantization.lattice.lattices import LineLattice
from qiskit_nature.problems.second_quantization.lattice.models import IsingModel

line = LineLattice(2)
ising = IsingModel.uniform_parameters(line, 2.0, 4.0)
print(ising.second_q_ops())  # Note: the trailing `s`

  Z_0 Z_1 * (2+0j)
+ X_0 * (4+0j)
+ X_1 * (4+0j)

Nuevo#

from qiskit_nature.second_q.hamiltonians.lattices import LineLattice
from qiskit_nature.second_q.hamiltonians import IsingModel

line = LineLattice(2)
ising = IsingModel(line.uniform_parameters(2.0, 4.0))
print(ising.second_q_op())  # Note: NO trailing `s`

Spin Operator
spin=1/2, number spins=2, number terms=3
  2.0 * ( Z_0 Z_1 )
+ 4.0 * ( X_0 )
+ 4.0 * ( X_1 )

IsingModel.from_parameters#

Previamente#

import numpy as np
from qiskit_nature.problems.second_quantization.lattice.models import IsingModel

interaction = np.array([[4.0, 2.0], [2.0, 4.0]])

ising = IsingModel.from_parameters(interaction)
print(ising.second_q_ops())  # Note: the trailing `s`

  X_0 * (4+0j)
+ Z_0 Z_1 * (2+0j)
+ X_1 * (4+0j)

Nuevo#

import numpy as np
from qiskit_nature.second_q.hamiltonians.lattices import Lattice
from qiskit_nature.second_q.hamiltonians import IsingModel

interaction = np.array([[4.0, 2.0], [2.0, 4.0]])

lattice = Lattice.from_adjacency_matrix(interaction)
ising = IsingModel(lattice)
print(ising.second_q_op())  # Note: NO trailing `s`

Spin Operator
spin=1/2, number spins=2, number terms=3
  4.0 * ( X_0 )
+ 2.0 * ( Z_0 Z_1 )
+ 4.0 * ( X_1 )