Decoding Quantum CSP Codes

import json
import numpy as np
from tqdm import tqdm
import qecstruct as qec
import matplotlib.pyplot as plt
from mdopt.optimiser.utils import (
    ConstraintString,
    IDENTITY,
    SWAP,
    XOR_BULK,
    XOR_LEFT,
    XOR_RIGHT,
)
from examples.decoding.decoding import (
    linear_code_constraint_sites,
    linear_code_prepare_message,
    linear_code_codewords,
)
from examples.decoding.decoding import (
    apply_bitflip_bias,
    apply_constraints,
    decode_linear,
)
from mdopt.mps.utils import (
    create_simple_product_state,
    create_custom_product_state,
)
from mdopt.utils.utils import mpo_to_matrix

f = open("data-csp-codes/batch_1/codes/qubits_30/code_0.json")
data = json.load(f)

data

{'x_stabs': [[1, 3, 5, 8, 10, 13, 14, 16, 27],
  [4, 8, 11, 12, 13, 14, 15, 18, 19, 21, 22, 24],
  [2, 3, 5, 8, 10, 15, 16, 17, 26, 29],
  [9, 11, 24, 25, 26, 27],
  [13, 16, 17, 18, 20, 22],
  [4, 5, 12, 20, 23, 28],
  [0, 5, 6, 8, 11, 17, 20, 21],
  [0, 1, 2, 6, 7, 9, 10, 11, 13, 14, 19, 24, 25],
  [6, 12, 14, 18, 19, 23],
  [2, 3, 4, 9, 16, 25, 28, 29],
  [6, 7, 9, 10, 12, 15, 28, 29],
  [1, 2, 6, 12, 13, 14, 16, 21, 22, 23, 27],
  [0, 2, 5, 7, 11, 26, 29]],
 'z_stabs': [[3, 5, 6, 8, 10, 11, 23, 25],
  [0, 6, 7, 9, 18, 22, 26, 29],
  [0, 2, 4, 10, 12, 14, 21],
  [4, 6, 10, 12, 13, 17, 19, 23, 28],
  [1, 9, 10, 11, 12, 13, 15, 16, 21, 23, 24, 26],
  [1, 5, 10, 16, 20, 29],
  [3, 6, 8, 12, 14, 19, 20, 21, 22, 25, 27],
  [0, 7, 9, 11, 15, 29],
  [1, 2, 3, 8, 21, 26, 27],
  [0, 1, 3, 5, 6, 14, 18, 20, 23, 28],
  [0, 2, 9, 10, 12, 13, 15, 17, 23, 24],
  [0, 8, 18, 19, 22, 26, 27],
  [2, 4, 7, 8, 16, 17, 28],
  [2, 5, 13, 20, 24, 25]],
 'num_qubits': 30}

data["x_stabs"]

[[1, 3, 5, 8, 10, 13, 14, 16, 27],
 [4, 8, 11, 12, 13, 14, 15, 18, 19, 21, 22, 24],
 [2, 3, 5, 8, 10, 15, 16, 17, 26, 29],
 [9, 11, 24, 25, 26, 27],
 [13, 16, 17, 18, 20, 22],
 [4, 5, 12, 20, 23, 28],
 [0, 5, 6, 8, 11, 17, 20, 21],
 [0, 1, 2, 6, 7, 9, 10, 11, 13, 14, 19, 24, 25],
 [6, 12, 14, 18, 19, 23],
 [2, 3, 4, 9, 16, 25, 28, 29],
 [6, 7, 9, 10, 12, 15, 28, 29],
 [1, 2, 6, 12, 13, 14, 16, 21, 22, 23, 27],
 [0, 2, 5, 7, 11, 26, 29]]

NUM_BITS = 60

state = create_simple_product_state(NUM_BITS, which="+")

code_constraint_sites = data["x_stabs"]
tensors = [XOR_LEFT, XOR_BULK, SWAP, XOR_RIGHT]
code_constraint_sites

[[1, 3, 5, 8, 10, 13, 14, 16, 27],
 [4, 8, 11, 12, 13, 14, 15, 18, 19, 21, 22, 24],
 [2, 3, 5, 8, 10, 15, 16, 17, 26, 29],
 [9, 11, 24, 25, 26, 27],
 [13, 16, 17, 18, 20, 22],
 [4, 5, 12, 20, 23, 28],
 [0, 5, 6, 8, 11, 17, 20, 21],
 [0, 1, 2, 6, 7, 9, 10, 11, 13, 14, 19, 24, 25],
 [6, 12, 14, 18, 19, 23],
 [2, 3, 4, 9, 16, 25, 28, 29],
 [6, 7, 9, 10, 12, 15, 28, 29],
 [1, 2, 6, 12, 13, 14, 16, 21, 22, 23, 27],
 [0, 2, 5, 7, 11, 26, 29]]