Files
hom_traj_gen/datasets/preprocessing/generator.py
2020-04-08 14:50:16 +02:00

118 lines
4.9 KiB
Python

import multiprocessing as mp
import pickle
import shelve
from collections import defaultdict
from pathlib import Path
from tqdm import tqdm
from ml_lib.objects.map import Map
class Generator:
possible_modes = ['one_patching']
def __init__(self, data_root, map_obj, binary=True):
self.binary: bool = binary
self.map: Map = map_obj
self.data_root = Path(data_root)
def generate_n_trajectories_m_alternatives(self, n, m, datafile_name, processes=0, **kwargs):
datafile_name = datafile_name if datafile_name.endswith('.pik') else f'{str(datafile_name)}.pik'
kwargs.update(n=m)
processes = processes if processes else mp.cpu_count() - 1
mutex = mp.Lock()
with mp.Pool(processes) as pool:
async_results = [pool.apply_async(self.generate_n_alternatives, kwds=kwargs) for _ in range(n)]
for result_obj in tqdm(async_results, total=n, desc='Producing trajectories with Alternatives'):
trajectory, alternatives, labels = result_obj.get()
mutex.acquire()
self.write_to_disk(datafile_name, trajectory, alternatives, labels)
mutex.release()
with shelve.open(str(self.data_root / datafile_name)) as f:
for datafile in self.data_root.glob(f'datafile_name*'):
with shelve.open(str(datafile)) as sub_f:
for key in sub_f.keys():
f[len(f)] = sub_f[key]
datafile.unlink()
pass
def generate_n_alternatives(self, n=None, datafile_name='', trajectory=None, is_sub_process=False,
mode='one_patching', equal_samples=True, binary_check=True):
assert n is not None, f'n is not allowed to be None but was: {n}'
assert mode in self.possible_modes, f'Parameter "mode" must be either {self.possible_modes}, but was {mode}.'
trajectory = trajectory if trajectory is not None else self.map.get_random_trajectory()
results = [self.map.generate_alternative(trajectory=trajectory, mode=mode) for _ in range(n)]
# label per homotopic class
homotopy_classes = defaultdict(list)
homotopy_classes[0].append(trajectory)
for i in range(len(results)):
alternative = results[i]
class_not_found = True
# check for homotopy class
for label in homotopy_classes.keys():
if self.map.are_homotopic(homotopy_classes[label][0], alternative):
homotopy_classes[label].append(alternative)
class_not_found = False
break
if class_not_found:
label = 1 if binary_check else len(homotopy_classes)
homotopy_classes[label].append(alternative)
# There should be as much homotopic samples as non-homotopic samples
if equal_samples:
homotopy_classes = self._remove_unequal(homotopy_classes)
if not homotopy_classes:
return None, None, None
# Compose lists of alternatives with labels
alternatives, labels = list(), list()
for key in homotopy_classes.keys():
alternatives.extend(homotopy_classes[key])
labels.extend([key] * len(homotopy_classes[key]))
if datafile_name:
if is_sub_process:
datafile_name = f'{str(datafile_name)}_{mp.current_process().pid}'
# Write to disk
self.write_to_disk(datafile_name, trajectory, alternatives, labels)
return trajectory, alternatives, labels
def write_to_disk(self, datafile_name, trajectory, alternatives, labels):
self.data_root.mkdir(exist_ok=True, parents=True)
with shelve.open(str(self.data_root / datafile_name), protocol=pickle.HIGHEST_PROTOCOL) as f:
new_key = len(f)
f[f'trajectory_{new_key}'] = dict(alternatives=alternatives,
trajectory=trajectory,
labels=labels)
if 'map' not in f:
f['map'] = dict(map=self.map, name=self.map.name)
@staticmethod
def _remove_unequal(hom_dict):
# We argue, that there will always be more non-homotopic routes than homotopic alternatives.
# TODO: Otherwise introduce a second condition / loop
hom_dict = hom_dict.copy()
if len(hom_dict[0]) <= 1:
return None
counter = len(hom_dict)
while sum([len(hom_dict[class_id]) for class_id in range(1, len(hom_dict))]) > len(hom_dict[0]):
if counter == 0:
counter = len(hom_dict)
if counter in hom_dict:
if len(hom_dict[counter]) == 0:
del hom_dict[counter]
else:
del hom_dict[counter][-1]
counter -= 1
return hom_dict