Pauli Correlation Encoding upang Bawasan ang Pangangailangan sa Maxcut

Pagtantya ng paggamit: 30 minuto sa isang Eagle r3 processor (PAALALA: Ito ay isang tantya lamang. Maaaring mag-iba ang inyong runtime.)

Konteksto

Ang tutorial na ito ay nagpapakita ng Pauli Correlation Encoding (PCE) [1], isang diskarte na idinisenyo upang mag-encode ng mga optimization problem sa mga qubit nang mas maayos para sa quantum computation. Ang PCE ay nagmamapa ng mga classical variable sa optimization problem tungo sa multi-body Pauli-matrix correlation, na nagreresulta sa polynomial compression ng space requirement ng problema. Sa pamamagitan ng paggamit ng PCE, ang bilang ng mga qubit na kailangan para sa pag-encode ay nabababawasan, na ginagawang partikular na kapaki-pakinabang ito para sa near-term quantum device na may limitadong qubit resource. Dagdag pa, napatunayan sa pamamagitan ng analytical method na ang PCE ay likas na nakakabawas ng barren plateau, na nag-aalok ng super-polynomial resilience laban sa phenomenong ito. Ang built-in na feature na ito ay nagpapahintulot ng walang kapantay na performance sa mga quantum optimization solver.

Pangkalahatang-ideya

Ang PCE approach ay binubuo ng tatlong pangunahing hakbang, gaya ng ipinakikita sa Figure 1 mula sa [1] sa ibaba:

1. Pag-encode ng optimization problem tungo sa isang Pauli correlation space.
2. Paglutas ng problema gamit ang quantum-classical optimization solver.
3. Pag-decode ng solusyon pabalik sa orihinal na optimization space. Ang PCE approach ay maaaring iangkop sa anumang quantum optimization solver na may kakayahang magproseso ng mga Pauli correlation matrix. Sa Figure 1 mula sa [1], ang Max-Cut problem ay ginagamit bilang halimbawa upang ilarawan ang PCE approach. Ang Max-Cut problem na may $m=9$ node ay ine-encode tungo sa isang Pauli correlation space, na kumakatawan sa optimization problem bilang correlation matrix, partikular na, 2-body Pauli-matrix correlation sa $n=3$ qubit $(Q_1, Q_2, Q_3)$. Ang mga kulay ng node ay nagsasaad ng Pauli string na ginagamit para sa bawat naka-encode na node. Halimbawa, ang node 1, na tumutugma sa binary variable $x_1$, ay ine-encode sa pamamagitan ng expectation value ng $Z_1 \otimes Z_2 \otimes I_3$, habang ang $x_8$ ay ine-encode ng $I_1 \otimes Y_2 \otimes Y_3$. Ito ay tumutugma sa pag-compress ng $m$ variable ng problema tungo sa $n = O(m^{1/2})$ qubit. Sa mas malawak na pag-unawa, ang $k$-body correlation ay nagpapahintulot ng polynomial compression na may order na $k$. Ang napiling Pauli set ay binubuo ng tatlong subset ng mutually-commuting Pauli string, na nagpapahintulot na ang lahat ng $m$ correlation ay matantya nang eksperimental gamit lamang ang tatlong measurement setting.

Ang isang loss function $\mathcal{L}$ ng mga Pauli expectation value na gumagaya sa orihinal na Max-Cut objective function ay ginagawa. Pagkatapos, ang loss function ay ino-optimize gamit ang quantum-classical optimization solver, gaya ng Variational Quantum Eigensolver (VQE).

Kapag natapos na ang optimization, ang solusyon ay dine-decode pabalik sa orihinal na optimization space, na nagbubunga ng optimal na Max-Cut solution.

Mga Pangangailangan

Bago simulan ang tutorial na ito, tiyaking mayroon kayo ng sumusunod na naka-install:

• Qiskit SDK v1.0 o mas bago, na may visualization support
• Qiskit Runtime v0.22 o mas bago (pip install qiskit-ibm-runtime)

Pag-setup

# Added by doQumentation — required packages for this notebook
!pip install -q networkx numpy qiskit qiskit-ibm-runtime rustworkx scipy

from itertools import combinations

import numpy as np
import rustworkx as rx
from scipy.optimize import minimize

from qiskit.circuit.library import efficient_su2
from qiskit.transpiler.preset_passmanagers import generate_preset_pass_manager
from qiskit.quantum_info import SparsePauliOp
from qiskit_ibm_runtime import EstimatorV2 as Estimator
from qiskit_ibm_runtime import QiskitRuntimeService
from qiskit_ibm_runtime import Session
from rustworkx.visualization import mpl_draw

service = QiskitRuntimeService()
backend = service.least_busy(
    operational=True, simulator=False, min_num_qubits=127
)

def calc_cut_size(graph, partition0, partition1):
    """Calculate the cut size of the given partitions of the graph."""

    cut_size = 0
    for edge0, edge1 in graph.edge_list():
        if edge0 in partition0 and edge1 in partition1:
            cut_size += 1
        elif edge0 in partition1 and edge1 in partition0:
            cut_size += 1
    return cut_size

Hakbang 1: Mag-map ng Mga Classical Input tungo sa Quantum Problem

Max-Cut Problem

Ang Max-Cut problem ay isang combinatorial optimization problem na tinukoy sa isang graph $G = (V, E)$, kung saan ang $V$ ay ang set ng mga vertex at ang $E$ ay ang set ng mga edge. Ang layunin ay hatiin ang mga vertex tungo sa dalawang set, $S$ at $V \setminus S$, sa paraang ang bilang ng mga edge sa pagitan ng dalawang set ay napapalaki. Para sa detalyadong paglalarawan ng Max-Cut problem, pakitingin ang "Quantum approximate optimization algorithm" tutorial. Gayundin, ang Max-Cut problem ay ginagamit bilang halimbawa sa tutorial na "Advanced Techniques for QAOA". Sa mga tutorial na iyon, ang QAOA algorithm ay ginagamit upang lutasin ang Max-Cut problem.

Graph -> Hamiltonian

Ang tutorial na ito ay gumagamit ng random graph na may 1000 node.

Ang laki ng problema ay maaaring mahirap i-visualize, kaya sa ibaba ay isang graph na may 100 node. (Ang pag-render ng graph na may 1,000 node nang direkta ay gagawing masyadong siksik upang makita ang anuman!) Ang graph na pinag-uusapan natin ay sampung beses na mas malaki.

mpl_draw(rx.undirected_gnp_random_graph(100, 0.1, seed=42))

num_nodes = 1000  # Number of nodes in graph
graph = rx.undirected_gnp_random_graph(num_nodes, 0.1, seed=42)

import networkx as nx

nx_graph = nx.Graph()
nx_graph.add_nodes_from(range(num_nodes))

for edge in graph.edge_list():
    nx_graph.add_edge(edge[0], edge[1])

curr_cut_size, partition = nx.approximation.one_exchange(nx_graph, seed=1)
print(f"Initial cut size: {curr_cut_size}")

Initial cut size: 28075

Ine-encode natin ang graph na may 1000 node tungo sa 2-body Pauli-matrix correlation sa 100 qubit. Ang graph ay kinakatawan bilang correlation matrix, kung saan ang bawat node ay ine-encode ng isang Pauli string. Ang sign ng expectation value ng Pauli string ay nagsasaad ng partition ng node. Halimbawa, ang node 0 ay ine-encode ng isang Pauli string, $\prod_0 = I_{19} \otimes ... I_2 \otimes X_1 \otimes X_0$. Ang sign ng expectation value ng Pauli string na ito ay nagsasaad ng partition ng node 0. Tinutukoy natin ang Pauli-correlation encoding (PCE) na nauukol sa $\prod$ bilang

$x_i \coloneqq \textit{sgn}(\langle\prod_i \rangle)$

kung saan ang $x_i$ ay ang partition ng node $i$ at ang $\langle \prod_i \rangle \coloneqq \langle \psi |\prod_i| \psi \rangle$ ay ang expectation value ng Pauli string na nag-eencode ng node $i$ sa isang quantum state na $|\psi \rangle$. Ngayon, i-encode natin ang graph tungo sa isang Hamiltonian gamit ang PCE. Hinahati natin ang mga node tungo sa tatlong set: $S_1$, $S_2$, at $S_3$. Pagkatapos, ine-encode natin ang mga node sa bawat set gamit ang mga Pauli string na may $X$, $Y$, at $Z$, ayon sa pagkakabanggit.

num_qubits = 100

list_size = num_nodes // 3
node_x = [i for i in range(list_size)]
node_y = [i for i in range(list_size, 2 * list_size)]
node_z = [i for i in range(2 * list_size, num_nodes)]

print("List 1:", node_x)
print("List 2:", node_y)
print("List 3:", node_z)

List 1: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332]
List 2: [333, 334, 335, 336, 337, 338, 339, 340, 341, 342, 343, 344, 345, 346, 347, 348, 349, 350, 351, 352, 353, 354, 355, 356, 357, 358, 359, 360, 361, 362, 363, 364, 365, 366, 367, 368, 369, 370, 371, 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384, 385, 386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396, 397, 398, 399, 400, 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 427, 428, 429, 430, 431, 432, 433, 434, 435, 436, 437, 438, 439, 440, 441, 442, 443, 444, 445, 446, 447, 448, 449, 450, 451, 452, 453, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463, 464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 475, 476, 477, 478, 479, 480, 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 491, 492, 493, 494, 495, 496, 497, 498, 499, 500, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541, 542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554, 555, 556, 557, 558, 559, 560, 561, 562, 563, 564, 565, 566, 567, 568, 569, 570, 571, 572, 573, 574, 575, 576, 577, 578, 579, 580, 581, 582, 583, 584, 585, 586, 587, 588, 589, 590, 591, 592, 593, 594, 595, 596, 597, 598, 599, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610, 611, 612, 613, 614, 615, 616, 617, 618, 619, 620, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642, 643, 644, 645, 646, 647, 648, 649, 650, 651, 652, 653, 654, 655, 656, 657, 658, 659, 660, 661, 662, 663, 664, 665]
List 3: [666, 667, 668, 669, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 690, 691, 692, 693, 694, 695, 696, 697, 698, 699, 700, 701, 702, 703, 704, 705, 706, 707, 708, 709, 710, 711, 712, 713, 714, 715, 716, 717, 718, 719, 720, 721, 722, 723, 724, 725, 726, 727, 728, 729, 730, 731, 732, 733, 734, 735, 736, 737, 738, 739, 740, 741, 742, 743, 744, 745, 746, 747, 748, 749, 750, 751, 752, 753, 754, 755, 756, 757, 758, 759, 760, 761, 762, 763, 764, 765, 766, 767, 768, 769, 770, 771, 772, 773, 774, 775, 776, 777, 778, 779, 780, 781, 782, 783, 784, 785, 786, 787, 788, 789, 790, 791, 792, 793, 794, 795, 796, 797, 798, 799, 800, 801, 802, 803, 804, 805, 806, 807, 808, 809, 810, 811, 812, 813, 814, 815, 816, 817, 818, 819, 820, 821, 822, 823, 824, 825, 826, 827, 828, 829, 830, 831, 832, 833, 834, 835, 836, 837, 838, 839, 840, 841, 842, 843, 844, 845, 846, 847, 848, 849, 850, 851, 852, 853, 854, 855, 856, 857, 858, 859, 860, 861, 862, 863, 864, 865, 866, 867, 868, 869, 870, 871, 872, 873, 874, 875, 876, 877, 878, 879, 880, 881, 882, 883, 884, 885, 886, 887, 888, 889, 890, 891, 892, 893, 894, 895, 896, 897, 898, 899, 900, 901, 902, 903, 904, 905, 906, 907, 908, 909, 910, 911, 912, 913, 914, 915, 916, 917, 918, 919, 920, 921, 922, 923, 924, 925, 926, 927, 928, 929, 930, 931, 932, 933, 934, 935, 936, 937, 938, 939, 940, 941, 942, 943, 944, 945, 946, 947, 948, 949, 950, 951, 952, 953, 954, 955, 956, 957, 958, 959, 960, 961, 962, 963, 964, 965, 966, 967, 968, 969, 970, 971, 972, 973, 974, 975, 976, 977, 978, 979, 980, 981, 982, 983, 984, 985, 986, 987, 988, 989, 990, 991, 992, 993, 994, 995, 996, 997, 998, 999]

def build_pauli_correlation_encoding(pauli, node_list, n, k=2):
    pauli_correlation_encoding = []
    for idx, c in enumerate(combinations(range(n), k)):
        if idx >= len(node_list):
            break
        paulis = ["I"] * n
        paulis[c[0]], paulis[c[1]] = pauli, pauli
        pauli_correlation_encoding.append(("".join(paulis)[::-1], 1))

    hamiltonian = []
    for pauli, weight in pauli_correlation_encoding:
        hamiltonian.append(SparsePauliOp.from_list([(pauli, weight)]))

    return hamiltonian

pauli_correlation_encoding_x = build_pauli_correlation_encoding(
    "X", node_x, num_qubits
)
pauli_correlation_encoding_y = build_pauli_correlation_encoding(
    "Y", node_y, num_qubits
)
pauli_correlation_encoding_z = build_pauli_correlation_encoding(
    "Z", node_z, num_qubits
)

Hakbang 2: I-optimize ang Problema para sa Quantum Hardware Execution

Quantum circuit

Dito, ang state na $|\psi \rangle$ ay may parameter na $\mathbf{\theta}$, at ino-optimize natin ang mga parameter na $\mathbf{\theta}$ na ito gamit ang variational approach. Ang tutorial na ito ay gumagamit ng efficient_su2 ansatz para sa ating variational algorithm dahil sa expressive capability at kadaling i-implement nito. Ginagamit din natin ang relaxed loss function, na ipapakita pa sa tutorial na ito. Bilang resulta, makakayanan nating lutasin ang mga large-scale problem gamit ang mas kaunting qubit at mas mababaw na circuit depth.

# Build the quantum circuit
qc = efficient_su2(num_qubits, ["ry", "rz"], reps=2)

# Optimize the circuit

pm = generate_preset_pass_manager(optimization_level=3, backend=backend)
qc = pm.run(qc)

Loss function

Para sa loss function na $\mathcal{L}$, gumagamit tayo ng relaxation ng Max-Cut objective function gaya ng inilarawan sa [1], na tinutukoy bilang $\mathcal{V}(\mathbf{x}) \coloneqq \sum_{(i, j) \in E} W_{i, j}(1-x_i x_j)$. Dito, ang $W_{i, j}$ ay nagsasaad ng weight ng edge na $(i, j)$, at ang $x_i$ ay kumakatawan sa partition ng node $i$. Ang loss function na $\mathcal{L}$ ay ibinibigay sa pamamagitan ng:

$\mathcal{L}\coloneqq \sum_{(i, j) \in E} W_{i, j} \text{tanh} (\alpha \langle\prod_i \rangle) \text{tanh} (\alpha \langle\prod_j \rangle) + \mathcal{L}^{(\text{reg})}$

kung saan ang Max-Cut objective function ay pinalitan ng smooth hyperbolic tangent ng mga expectation value ng mga Pauli string na nag-eencode sa mga node. Ang regularization term na $\mathcal{L}^{(\text{reg})}$ at ang rescaling factor na $\alpha$, na proporsyonal sa bilang ng mga qubit, ay ipinakilala upang mapabuti ang performance ng solver.

Ang regularization term ay tinutukoy bilang:

Ang $\mathcal{L}^{(\text{reg})}$ ay tinutukoy bilang $\mathcal{L}^{(\text{reg})} \coloneqq \beta \nu \lbrack \frac{1}{m} \sum_{i \in V} \text{tanh} (\alpha \langle\prod_i \rangle)^2 \rbrack ^2$

kung saan ang $\beta=1/2$, $\nu = |E|/2 + (m -1) /4$, at ang $m$ ay ang bilang ng mga node sa graph.

def loss_func_estimator(x, ansatz, hamiltonian, estimator, graph):
    """
    Calculates the specified loss function for the given ansatz, Hamiltonian, and graph.

    The expectation values of each Pauli string in the Hamiltonian are first obtained
    by running the ansatz on the quantum backend. These expectation values are then
    passed through the nonlinear function tanh(alpha * prod_i). The loss function is
    subsequently computed from these transformed values.
    """
    job = estimator.run(
        [
            (ansatz, hamiltonian[0], x),
            (ansatz, hamiltonian[1], x),
            (ansatz, hamiltonian[2], x),
        ]
    )
    result = job.result()

    # calculate the loss function
    node_exp_map = {}
    idx = 0
    for r in result:
        for ev in r.data.evs:
            node_exp_map[idx] = ev
            idx += 1

    loss = 0
    alpha = num_qubits
    for edge0, edge1 in graph.edge_list():
        loss += np.tanh(alpha * node_exp_map[edge0]) * np.tanh(
            alpha * node_exp_map[edge1]
        )

    regulation_term = 0
    for i in range(len(graph.nodes())):
        regulation_term += np.tanh(alpha * node_exp_map[i]) ** 2
    regulation_term = regulation_term / len(graph.nodes())
    regulation_term = regulation_term**2
    beta = 1 / 2
    v = len(graph.edges()) / 2 + (len(graph.nodes()) - 1) / 4
    regulation_term = beta * v * regulation_term

    loss = loss + regulation_term

    global experiment_result
    print(f"Iter {len(experiment_result)}: {loss}")
    experiment_result.append({"loss": loss, "exp_map": node_exp_map})
    return loss

Hakbang 3: Magsagawa gamit ang Mga Qiskit Primitive

Sa tutorial na ito, itinakda nating max_iter=50 para sa optimization loop para sa demonstration purpose. Kung patatasin natin ang bilang ng mga iteration, maaari tayong umasa ng mas magandang resulta.

pce = []
pce.append(
    [op.apply_layout(qc.layout) for op in pauli_correlation_encoding_x]
)
pce.append(
    [op.apply_layout(qc.layout) for op in pauli_correlation_encoding_y]
)
pce.append(
    [op.apply_layout(qc.layout) for op in pauli_correlation_encoding_z]
)

# Run the optimization using Session

with Session(backend=backend) as session:
    estimator = Estimator(mode=session)

    experiment_result = []

    def loss_func(x):
        return loss_func_estimator(
            x, qc, [pce[0], pce[1], pce[2]], estimator, graph
        )

    np.random.seed(42)
    initial_params = np.random.rand(qc.num_parameters)
    result = minimize(
        loss_func, initial_params, method="COBYLA", options={"maxiter": 50}
    )
print(result)

Iter 0: 16659.649201600296
Iter 1: 12104.242957555361
Iter 2: 6541.137221994661
Iter 3: 6650.6188244671985
Iter 4: 7033.193518185085
Iter 5: 6743.687931793412
Iter 6: 6223.574718684094
Iter 7: 6457.3302709535965
Iter 8: 6581.316449107595
Iter 9: 6365.761052029896
Iter 10: 6415.872673527322
Iter 11: 6421.996561600348
Iter 12: 6636.372822791712
Iter 13: 6965.174320702346
Iter 14: 6774.236562696287
Iter 15: 6393.837617108355
Iter 16: 6234.311401676519
Iter 17: 6518.192237615901
Iter 18: 6559.933925068997
Iter 19: 6646.157979243488
Iter 20: 6573.726111605048
Iter 21: 6190.642092901959
Iter 22: 6653.06500163594
Iter 23: 6545.713700369988
Iter 24: 6399.996441760465
Iter 25: 6115.959687941808
Iter 26: 6665.915093554849
Iter 27: 6832.882201259893
Iter 28: 6541.392749578919
Iter 29: 6813.3456910443165
Iter 30: 6460.800944368402
Iter 31: 6359.635437029245
Iter 32: 6040.891641882451
Iter 33: 6573.930674936448
Iter 34: 6668.031753293785
Iter 35: 6450.002712889748
Iter 36: 6519.8298811058075
Iter 37: 6467.134502398199
Iter 38: 6655.284651397334
Iter 39: 6371.168353987336
Iter 40: 6480.337259347923
Iter 41: 6339.256786764425
Iter 42: 6588.635046825541
Iter 43: 6617.677964971322
Iter 44: 6469.0441600679205
Iter 45: 6567.874244906106
Iter 46: 6217.899975264532
Iter 47: 6783.481394627947
Iter 48: 6813.371853626112
Iter 49: 6506.5871531488765
 message: Maximum number of function evaluations has been exceeded.
 success: False
  status: 2
     fun: 6040.891641882451
       x: [ 1.375e+00  1.951e+00 ...  1.923e-01  4.087e-02]
    nfev: 50
   maxcv: 0.0

Hakbang 4: Mag-post-process at Ibalik ang Resulta sa Nais na Classical Format

Ang mga partition ng mga node ay tinutukoy sa pamamagitan ng pagsusuri sa sign ng mga expectation value ng mga Pauli string na nag-eencode sa mga node.

# Calculate the partitions based on the final expectation values
# If the expectation value is positive, the node belongs to partition 0 (par0)
# Otherwise, the node belongs to partition 1 (par1)

par0, par1 = set(), set()

for i in experiment_result[-1]["exp_map"]:
    if experiment_result[-1]["exp_map"][i] >= 0:
        par0.add(i)
    else:
        par1.add(i)
print(par0, par1)

{0, 1, 4, 8, 9, 10, 12, 13, 14, 15, 16, 18, 25, 27, 31, 32, 34, 36, 38, 39, 40, 41, 44, 46, 47, 48, 49, 50, 51, 52, 57, 60, 61, 62, 63, 64, 65, 66, 68, 71, 79, 81, 82, 86, 88, 91, 92, 93, 94, 95, 96, 99, 100, 105, 106, 107, 112, 114, 115, 121, 123, 129, 133, 134, 145, 147, 161, 165, 166, 168, 171, 173, 184, 185, 187, 188, 192, 193, 194, 196, 197, 198, 202, 205, 206, 207, 208, 209, 210, 211, 215, 217, 218, 219, 220, 221, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 238, 241, 242, 243, 244, 246, 247, 248, 249, 251, 252, 253, 255, 256, 257, 258, 259, 261, 262, 264, 265, 266, 268, 269, 270, 272, 273, 275, 276, 277, 278, 279, 281, 283, 284, 285, 286, 288, 292, 293, 294, 299, 300, 303, 305, 306, 307, 308, 310, 312, 313, 314, 316, 317, 319, 321, 326, 327, 328, 333, 336, 338, 340, 341, 342, 344, 345, 346, 349, 351, 352, 353, 356, 357, 360, 361, 362, 363, 364, 366, 368, 370, 374, 378, 379, 380, 381, 382, 383, 384, 386, 387, 388, 389, 390, 391, 393, 394, 395, 396, 397, 398, 404, 405, 406, 409, 411, 413, 415, 416, 418, 421, 425, 426, 427, 428, 429, 433, 434, 435, 437, 444, 450, 456, 457, 458, 459, 462, 463, 465, 467, 469, 470, 472, 476, 479, 484, 487, 489, 492, 493, 497, 498, 499, 502, 506, 508, 513, 516, 517, 518, 519, 521, 523, 526, 527, 528, 531, 532, 533, 535, 536, 537, 539, 540, 541, 542, 543, 544, 545, 547, 549, 550, 552, 557, 562, 563, 564, 565, 567, 568, 569, 570, 571, 572, 573, 576, 578, 579, 580, 583, 585, 587, 588, 589, 591, 595, 596, 597, 600, 602, 603, 604, 605, 606, 607, 608, 609, 610, 612, 618, 619, 623, 624, 625, 626, 627, 628, 630, 632, 636, 637, 640, 644, 646, 649, 652, 656, 657, 658, 659, 661, 662, 663, 664, 667, 669, 670, 671, 672, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 690, 692, 693, 694, 695, 696, 698, 700, 701, 703, 706, 707, 708, 709, 712, 713, 714, 716, 717, 718, 719, 721, 722, 723, 724, 725, 726, 728, 730, 731, 733, 734, 735, 737, 739, 740, 741, 743, 744, 746, 748, 750, 751, 752, 753, 754, 758, 760, 761, 762, 763, 764, 765, 766, 774, 778, 780, 782, 787, 795, 800, 802, 803, 808, 809, 812, 818, 822, 825, 827, 834, 836, 840, 843, 845, 847, 850, 853, 854, 857, 858, 863, 864, 865, 866, 867, 868, 869, 870, 872, 873, 874, 875, 876, 878, 880, 881, 882, 883, 884, 885, 887, 888, 889, 890, 891, 893, 894, 895, 896, 898, 901, 902, 903, 904, 905, 907, 908, 910, 911, 912, 913, 914, 915, 916, 917, 918, 920, 921, 923, 925, 926, 928, 929, 930, 932, 934, 935, 936, 938, 939, 941, 943, 945, 946, 947, 948, 949, 953, 955, 956, 957, 958, 959, 961, 966, 975, 978, 980, 983, 988, 990, 996, 999} {2, 3, 5, 6, 7, 11, 17, 19, 20, 21, 22, 23, 24, 26, 28, 29, 30, 33, 35, 37, 42, 43, 45, 53, 54, 55, 56, 58, 59, 67, 69, 70, 72, 73, 74, 75, 76, 77, 78, 80, 83, 84, 85, 87, 89, 90, 97, 98, 101, 102, 103, 104, 108, 109, 110, 111, 113, 116, 117, 118, 119, 120, 122, 124, 125, 126, 127, 128, 130, 131, 132, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 146, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 162, 163, 164, 167, 169, 170, 172, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 186, 189, 190, 191, 195, 199, 200, 201, 203, 204, 212, 213, 214, 216, 222, 223, 224, 237, 239, 240, 245, 250, 254, 260, 263, 267, 271, 274, 280, 282, 287, 289, 290, 291, 295, 296, 297, 298, 301, 302, 304, 309, 311, 315, 318, 320, 322, 323, 324, 325, 329, 330, 331, 332, 334, 335, 337, 339, 343, 347, 348, 350, 354, 355, 358, 359, 365, 367, 369, 371, 372, 373, 375, 376, 377, 385, 392, 399, 400, 401, 402, 403, 407, 408, 410, 412, 414, 417, 419, 420, 422, 423, 424, 430, 431, 432, 436, 438, 439, 440, 441, 442, 443, 445, 446, 447, 448, 449, 451, 452, 453, 454, 455, 460, 461, 464, 466, 468, 471, 473, 474, 475, 477, 478, 480, 481, 482, 483, 485, 486, 488, 490, 491, 494, 495, 496, 500, 501, 503, 504, 505, 507, 509, 510, 511, 512, 514, 515, 520, 522, 524, 525, 529, 530, 534, 538, 546, 548, 551, 553, 554, 555, 556, 558, 559, 560, 561, 566, 574, 575, 577, 581, 582, 584, 586, 590, 592, 593, 594, 598, 599, 601, 611, 613, 614, 615, 616, 617, 620, 621, 622, 629, 631, 633, 634, 635, 638, 639, 641, 642, 643, 645, 647, 648, 650, 651, 653, 654, 655, 660, 665, 666, 668, 673, 691, 697, 699, 702, 704, 705, 710, 711, 715, 720, 727, 729, 732, 736, 738, 742, 745, 747, 749, 755, 756, 757, 759, 767, 768, 769, 770, 771, 772, 773, 775, 776, 777, 779, 781, 783, 784, 785, 786, 788, 789, 790, 791, 792, 793, 794, 796, 797, 798, 799, 801, 804, 805, 806, 807, 810, 811, 813, 814, 815, 816, 817, 819, 820, 821, 823, 824, 826, 828, 829, 830, 831, 832, 833, 835, 837, 838, 839, 841, 842, 844, 846, 848, 849, 851, 852, 855, 856, 859, 860, 861, 862, 871, 877, 879, 886, 892, 897, 899, 900, 906, 909, 919, 922, 924, 927, 931, 933, 937, 940, 942, 944, 950, 951, 952, 954, 960, 962, 963, 964, 965, 967, 968, 969, 970, 971, 972, 973, 974, 976, 977, 979, 981, 982, 984, 985, 986, 987, 989, 991, 992, 993, 994, 995, 997, 998}

Makakalkula natin ang cut size ng Max-Cut problem gamit ang mga partition ng node.

cut_size = calc_cut_size(graph, par0, par1)
print(f"Cut size: {cut_size}")

Cut size: 24682

Pagkatapos matapos ang training, nagsasagawa tayo ng isang round ng single-bit swap search upang mapabuti ang solusyon bilang isang classical post-processing step. Sa prosesong ito, pinag-papalitan natin ang mga partition ng dalawang node at sinusuri ang cut size. Kung ang cut size ay napabuti, pinapanatili natin ang swap. Inuulit natin ang prosesong ito para sa lahat ng posibleng pares ng mga node na konektado ng isang edge.

best_bits = []
cur_bits = []

for i in experiment_result[-1]["exp_map"]:
    if experiment_result[-1]["exp_map"][i] >= 0:
        cur_bits.append(1)
    else:
        cur_bits.append(0)
print(cur_bits)

[1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1]

# Swap the partitions and calculate the cut size
best_cut = 0
for edge0, edge1 in graph.edge_list():
    swapped_bits = cur_bits.copy()
    swapped_bits[edge0], swapped_bits[edge1] = (
        swapped_bits[edge1],
        swapped_bits[edge0],
    )

    cur_partition = [set(), set()]
    for i, bit in enumerate(swapped_bits):
        if bit > 0:
            cur_partition[0].add(i)
        else:
            cur_partition[1].add(i)
    cut_size = calc_cut_size(graph, cur_partition[0], cur_partition[1])
    if best_cut < cut_size:
        best_cut = cut_size
        best_bits = swapped_bits

print(best_cut, best_bits)

24733 [1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1]

Mga Sanggunian

[1] Sciorilli, M., Borges, L., Patti, T. L., García-Martín, D., Camilo, G., Anandkumar, A., & Aolita, L. (2024). Towards large-scale quantum optimization solvers with few qubits. arXiv preprint arXiv:2401.09421.

Survey ng Tutorial

Mangyaring sagutin ang maikling survey na ito upang magbigay ng feedback tungkol sa tutorial na ito. Ang inyong mga pananaw ay makakatulong sa amin na mapabuti ang aming mga pagkakaloob ng nilalaman at karanasan ng mga user.

Link sa survey