def greedy():
""" Run greedy hillclimber. Enumerate neighbourhood and choose best. """
chain = hchain.HeisenbergChain(num_qubits, v)
steps = [-step_size, 0, step_size]
neighbourhood_size = len(steps)**num_p_values
suzuki = np.array(approx.suzuki(k))
suzuki_error = approx.error(chain, approx.r_copies(suzuki, r), t)
print('Suzuki error: {}'.format(suzuki_error))
# Start at Suzuki
current = suzuki
current_error = suzuki_error
# Start at 1/p_length
# current = np.array([0.2] * 5)
# current_error = approx.error(chain, approx.r_copies(current, r), t)
# Start at suzuki permutation
# import random
# random.seed(1234)
# suzuki_coeff = approx.suzuki(k)
# random.shuffle(suzuki_coeff)
# current = np.array(suzuki_coeff)
# current_error = approx.error(chain, approx.r_copies(current, r), t)
for gen in range(1, gens+1):
current_error_percent = 100 * (current_error / suzuki_error)
print('Gen: {} Best: {} Percent: {} '.format(gen, current_error, current_error_percent))
all_neighbours = list(range(1, neighbourhood_size))
random.shuffle(all_neighbours
)
for neighbour_index in all_neighbours:
move = [step_size * (coeff - 1) for coeff in ternary(neighbour_index, num_p_values)]
neighbour = current + move
neighbour_err = approx.error(chain, approx.r_copies(neighbour, r), t)
neighbour_err_percent = 100 * (neighbour_err / suzuki_error)
print('Step {} Neighbour {}/{} error: {}, error %: {}'.format(gen, neighbour_index, neighbourhood_size,
neighbour_err, neighbour_err_percent))
if neighbour_err < current_error:
current = neighbour
current_error = neighbour_err
current_error_percent = 100 * (current_error / suzuki_error)
print('New best: error: {} percent: {} solution: {})'.format(current_error, current_error_percent,
current))
break
def compare_lambda_over_n(input_df, start_row, end_row, output_folder_path):
df = input_df.copy()
df.insert(1, 'optimised error', None)
df.insert(1, 'suzuki error', None)
df.insert(1, '%', None)
if not os.path.isdir(output_folder_path):
os.makedirs(output_folder_path)
output_data_path = os.path.join(
output_folder_path, 'output_{}_{}.csv'.format(start_row, end_row))
for row_id in range(start_row - 1, end_row):
row = df.loc[row_id]
n = int(row['n'])
v = list(map(float, list(row['v_1':'v_%d' % n])))
k = int(row['k'])
r = int(row['r'])
p = list(row.loc['p_1':'p_%d' % (5**(k - 1))])
chain = hchain.HeisenbergChain(n, v)
suz_err = approx.error(chain, approx.suzuki_solution(k, r), t=2 * n)
op_err = approx.error(chain, approx.r_copies(p, r), t=2 * n)
perc = 100 * op_err / suz_err
df.loc[row_id, 'suzuki error'] = suz_err
df.loc[row_id, 'optimised error'] = op_err
df.loc[row_id, '%'] = perc
df.dropna(inplace=True)
df.to_csv(output_data_path, index=False)
def suzuki_sampling(input_df, start_row, end_row, output_folder_path):
df = input_df.copy()
NUM_SAMPLES = 100
for row_id in range(start_row-1, end_row):
row = df.loc[row_id]
n = int(row['n'])
v = row['v_1':'v_%d' % n]
k = int(row['k'])
r = int(row['r'])
scale = float(row['scale'])
cols = ['n'] + ['v_%d' % i for i in range(1, n+1)] + ['k', 'r', 'scale', 'sampled error', 'suzuki error']
row_df = pd.DataFrame(columns=cols)
chain = hchain.HeisenbergChain(n, v)
sample_length = (5**(k-1))
suzuki_vector = approx.suzuki(k)
for _ in range(NUM_SAMPLES):
noise = np.random.normal(loc=0, scale=scale/sample_length, size=sample_length)
sample_vector = np.array(suzuki_vector) + noise
sampled_err = approx.error(chain, approx.r_copies(sample_vector, r), t=2*n)
suz_err = approx.error(chain, approx.suzuki_solution(k, r), t=2*n)
row_df.loc[len(row_df)+1] = [n] + list(v) + [k, r, scale, sampled_err, suz_err]
row_df.to_csv(os.path.join(output_folder_path, 'row_%d.csv'%(row_id+1)))
def target_error(ind):
if NORMALISE:
norm_ind = norm_f(ind)
else:
norm_ind = ind
final_ind = approx.r_copies(approx.expand_vals(ind), r)
return approx.error(chain, final_ind, t=2 * chain.n),
def greedy():
""" Run greedy hillclimber. Enumerate neighbourhood and choose best. """
random.seed(1234)
chain = hchain.HeisenbergChain(num_qubits, v)
suzuki = np.array(approx.suzuki(k))
suzuki_error = approx.error(chain, approx.r_copies(suzuki, r), t)
print('Suzuki error: {}'.format(suzuki_error))
# Start at Suzuki
current = suzuki
current_error = suzuki_error
for gen in range(1, gens + 1):
current_error_percent = 100 * (current_error / suzuki_error)
print('Gen: {} Best: {} Percent: {} '.format(gen, current_error,
current_error_percent))
first = random.randint(1, num_p_values)
second = random.randint(1, num_p_values)
neighbour = current.copy()
neighbour[first - 1] = neighbour[first - 1] + step_size
neighbour[second - 1] = neighbour[second - 1] - step_size
neighbour_err = approx.error(chain, approx.r_copies(neighbour, r), t)
neighbour_err_percent = 100 * (neighbour_err / suzuki_error)
print('Step {} error: {}, error %: {}'.format(gen, neighbour_err,
neighbour_err_percent))
if neighbour_err < current_error:
current = neighbour
current_error = neighbour_err
current_error_percent = 100 * (current_error / suzuki_error)
print('New best: error: {} percent: {} solution: {})'.format(
current_error, current_error_percent, current))
def run(input_file, start, end):
if not os.path.isdir(OUTPUT_DIR):
os.makedirs(OUTPUT_DIR)
input_file_prefix = os.path.splitext(os.path.basename(input_file))[0]
output_file = os.path.join(
OUTPUT_DIR, input_file_prefix + '_output_{}_{}.csv'.format(start, end))
header, all_rows = read_all(input_file)
with open(output_file, 'w') as outcsv:
output_header = header + ['suzuki error', 'optimised error', '%']
writer = csv.DictWriter(outcsv, output_header)
writer.writeheader()
for row in all_rows[start - 1:end]:
n = int(row['n'])
k = int(row['k'])
r = int(row['r'])
t = int(row['t'])
p_vect = {k: v for k, v in row.items() if k.startswith('p_')}
v_vect = {
k: v
for k, v in row.items() if k.startswith('v_') and v != ''
}
v_values = [float(v) for v in v_vect.values()]
p_values = [float(p) for p in p_vect.values()]
chain = hchain.HeisenbergChain(n, v_values)
suz_err = approx.error(chain, approx.suzuki_solution(k, r), t)
op_err = approx.error(chain, approx.r_copies(p_values, r), t)
percentage = 100 * op_err / suz_err
row['suzuki error'] = suz_err
row['optimised error'] = op_err
row['%'] = percentage
writer.writerow(row)
def evaluate_rows(input_df, start_row, end_row, output_folder_path):
df = input_df.copy()
if not os.path.isdir(output_folder_path):
os.makedirs(output_folder_path)
logs_path = os.path.join(output_folder_path, 'logs')
if not os.path.isdir(logs_path):
os.makedirs(logs_path)
output_data_path = os.path.join(output_folder_path, 'output_{}_{}.csv'.format(start_row, end_row))
for row_id in range(start_row-1, end_row):
row = df.loc[row_id]
n = int(row['n'])
v = row['v_1':'v_%d' % n]
k = int(row['k'])
r = int(row['r'])
seed = int(row['seed'])
gens = int(row['gens'])
chain = hchain.HeisenbergChain(n, v)
t = time.time()
pop, log, hof = run_cmaes_p(v=v, k=k, r=r, seed=seed, generations=gens)
t = time.time() - t
best = hof[0]
suz_err = approx.error(chain,approx.suzuki_solution(k, r),t=2*n)
op_err = approx.error(chain,approx.r_copies(best, r),t=2*n)
perc = 100*op_err/suz_err
for j in range(1,5**(k-1)+1):
df.loc[row_id,'p_%d'%j] = best[j-1]
df.loc[row_id,'optimised error'] = op_err
df.loc[row_id, 'suzuki error'] = suz_err
df.loc[row_id, '% error'] = perc
df.loc[row_id, 'time'] = t
pd.DataFrame(log).to_csv(os.path.join(logs_path, 'row_{}.csv'.format(row_id + 1)), index=False)
df.dropna(inplace=True)
df.to_csv(output_data_path, index=False)
def testRcopies(self):
x = [1] * 10
r = 30
expected = [1 / 30] * 300
self.assertTrue(np.allclose(expected, approx.r_copies(x, r)))
def target_error(ind):
final_ind = approx.r_copies(ind, int((r * 5**(k - 1)) / len(ind)))
return approx.error(chain, final_ind, t=2 * chain.n),
