"""
data generator for feeding data into pytorch models
"""
import json
import time
from copy import deepcopy
from functools import reduce
from pathlib import Path
from random import sample, shuffle
from typing import List, Optional, Sequence, Set, Tuple
import numpy as np
import torch
from torch.utils.data.dataset import Dataset
from tqdm.auto import tqdm
try:
import torch_ecg # noqa: F401
except ModuleNotFoundError:
import sys
sys.path.insert(0, str(Path(__file__).absolute().parents[2]))
from cfg import ModelCfg, TrainCfg
from torch_ecg._preprocessors import PreprocManager
from torch_ecg.cfg import CFG
from torch_ecg.databases import CINC2020 as CR
from torch_ecg.utils.misc import ReprMixin, ensure_siglen, list_sum
from torch_ecg.utils.utils_signal import remove_spikes_naive
if ModelCfg.torch_dtype == torch.float64:
torch.set_default_tensor_type(torch.DoubleTensor)
__all__ = [
"CINC2020",
]
class CINC2020(ReprMixin, Dataset):
""" """
__DEBUG__ = False
__name__ = "CINC2020"
def __init__(self, config: CFG, training: bool = True, lazy: bool = True) -> None:
"""
Parameters
----------
config: dict,
configurations for the Dataset,
ref. `cfg.TrainCfg`
training: bool, default True,
if True, the training set will be loaded, otherwise the test set
lazy: bool, default True,
if True, the data will not be loaded immediately
"""
super().__init__()
self.config = deepcopy(config)
assert self.config.db_dir is not None, "db_dir must be specified"
self.config.db_dir = Path(self.config.db_dir)
self._TRANCHES = self.config.tranche_classes.keys() # ["A", "B", "AB", "E", "F"]
self.reader = CR(db_dir=self.config.db_dir)
self.tranches = self.config.tranches_for_training
self.training = training
if self.config.torch_dtype == torch.float64:
self.dtype = np.float64
else:
self.dtype = np.float32
assert not self.tranches or self.tranches in self._TRANCHES
if self.tranches:
self.all_classes = self.config.tranche_classes[self.tranches]
self.class_weights = self.config.tranche_class_weights[self.tranches]
else:
self.all_classes = self.config.classes
self.class_weights = self.config.class_weights
self.config.all_classes = deepcopy(self.all_classes)
self.n_classes = len(self.all_classes)
# print(f"tranches = {self.tranches}, all_classes = {self.all_classes}")
# print(f"class_weights = {dict_to_str(self.class_weights)}")
cw = np.zeros((len(self.class_weights),), dtype=self.dtype)
for idx, c in enumerate(self.all_classes):
cw[idx] = self.class_weights[c]
self.class_weights = torch.from_numpy(cw.astype(self.dtype)).view(1, self.n_classes)
# validation also goes in batches, hence length has to be fixed
self.siglen = self.config.input_len
self.lazy = lazy
self.records = self._train_test_split(self.config.train_ratio, force_recompute=False)
# TODO: consider using `remove_spikes_naive` to treat these exceptional records
self.records = [r for r in self.records if r not in self.reader.exceptional_records]
if self.__DEBUG__:
self.records = sample(self.records, int(len(self.records) * 0.01))
ppm_config = CFG(random=False)
ppm_config.update(self.config)
self.ppm = PreprocManager.from_config(ppm_config)
# self.ppm.rearrange(["bandpass", "normalize"])
self._signals = np.array([], dtype=self.dtype).reshape(0, len(self.config.leads), self.siglen)
self._labels = np.array([], dtype=self.dtype).reshape(0, self.n_classes)
if not self.lazy:
self._load_all_data()
def _load_all_data(self) -> None:
""" """
fdr = FastDataReader(self.reader, self.records, self.config, self.ppm)
self._signals, self._labels = [], []
with tqdm(
range(len(fdr)),
desc="Loading data",
unit="records",
dynamic_ncols=True,
mininterval=1.0,
) as pbar:
for idx in pbar:
sig, lb = fdr[idx]
self._signals.append(sig)
self._labels.append(lb)
self._signals = np.concatenate(self._signals, axis=0).astype(self.dtype)
self._labels = np.concatenate(self._labels, axis=0)
def _load_one_record(self, rec: str) -> Tuple[np.ndarray, np.ndarray]:
"""
load a record from the database using data reader
NOTE
----
DO NOT USE THIS FUNCTION DIRECTLY for preloading data,
use `FastDataReader` instead
Parameters
----------
rec: str,
the record to load
Returns
-------
values: np.ndarray,
the values of the record
labels: np.ndarray,
the labels of the record
"""
values = self.reader.load_resampled_data(rec, data_format=self.config.data_format, siglen=None)
for idx in range(values.shape[0]):
values[idx] = remove_spikes_naive(values[idx])
values, _ = self.ppm(values, self.config.fs)
values = ensure_siglen(
values,
siglen=self.siglen,
fmt=self.config.data_format,
tolerance=self.config.sig_slice_tol,
).astype(self.dtype)
if values.ndim == 2:
values = values[np.newaxis, ...]
labels = self.reader.get_labels(rec, scored_only=True, fmt="a", normalize=True)
labels = np.isin(self.all_classes, labels).astype(self.dtype)[np.newaxis, ...].repeat(values.shape[0], axis=0)
return values, labels
@property
def signals(self) -> np.ndarray:
""" """
return self._signals
@property
def labels(self) -> np.ndarray:
""" """
return self._labels
def __getitem__(self, index: int) -> Tuple[np.ndarray, np.ndarray]:
""" """
return self.signals[index], self.labels[index]
def __len__(self) -> int:
""" """
return len(self._signals)
def _train_test_split(self, train_ratio: float = 0.8, force_recompute: bool = False) -> List[str]:
"""
do train test split,
it is ensured that both the train and the test set contain all classes
Parameters
----------
train_ratio: float, default 0.8,
ratio of the train set in the whole dataset (or the whole tranche(s))
force_recompute: bool, default False,
if True, force redo the train-test split,
regardless of the existing ones stored in json files
Returns
-------
records: list of str,
list of the records split for training or validation
"""
time.sleep(1)
start = time.time()
print("\nstart performing train test split...\n")
time.sleep(1)
_TRANCHES = list("ABEF")
_train_ratio = int(train_ratio * 100)
_test_ratio = 100 - _train_ratio
assert _train_ratio * _test_ratio > 0
ns = "_ns" if len(self.config.special_classes) == 0 else ""
file_suffix = f"_siglen_{self.siglen}{ns}.json"
train_file = self.reader.db_dir_base / f"train_ratio_{_train_ratio}{file_suffix}"
test_file = self.reader.db_dir_base / f"test_ratio_{_test_ratio}{file_suffix}"
if force_recompute or not all([train_file.is_file(), test_file.is_file()]):
tranche_records = {t: [] for t in _TRANCHES}
train_set = {t: [] for t in _TRANCHES}
test_set = {t: [] for t in _TRANCHES}
for t in _TRANCHES:
with tqdm(
self.reader.all_records[t],
total=len(self.reader.all_records[t]),
dynamic_ncols=True,
mininterval=1.0,
) as bar:
for rec in bar:
if rec in self.reader.exceptional_records:
# skip exceptional records
continue
rec_labels = self.reader.get_labels(rec, scored_only=True, fmt="a", normalize=True)
rec_labels = [c for c in rec_labels if c in TrainCfg.tranche_classes[t]]
if len(rec_labels) == 0:
# skip records with no scored class
continue
rec_samples = self.reader.load_resampled_data(rec).shape[1]
if rec_samples < self.siglen:
continue
tranche_records[t].append(rec)
print(f"tranche {t} has {len(tranche_records[t])} valid records for training")
for t in _TRANCHES:
is_valid = False
while not is_valid:
shuffle(tranche_records[t])
split_idx = int(len(tranche_records[t]) * train_ratio)
train_set[t] = tranche_records[t][:split_idx]
test_set[t] = tranche_records[t][split_idx:]
is_valid = self._check_train_test_split_validity(
train_set[t], test_set[t], set(TrainCfg.tranche_classes[t])
)
train_file.write_text(json.dumps(train_set, ensure_ascii=False))
test_file.write_text(json.dumps(test_set, ensure_ascii=False))
else:
train_set = json.loads(train_file.read_text())
test_set = json.loads(test_file.read_text())
_tranches = list(self.tranches or "ABEF")
if self.training:
records = list_sum([train_set[k] for k in _tranches])
else:
records = list_sum([test_set[k] for k in _tranches])
return records
def _check_train_test_split_validity(self, train_set: List[str], test_set: List[str], all_classes: Set[str]) -> bool:
"""
the train-test split is valid iff
records in both `train_set` and `test` contain all classes in `all_classes`
Parameters
----------
train_set: list of str,
list of the records in the train set
test_set: list of str,
list of the records in the test set
all_classes: set of str,
the set of all classes for training
Returns
-------
is_valid: bool,
the split is valid or not
"""
def add(a, b):
return a + b
train_classes = set(reduce(add, [self.reader.get_labels(rec, fmt="a") for rec in train_set]))
train_classes.intersection_update(all_classes)
test_classes = set(reduce(add, [self.reader.get_labels(rec, fmt="a") for rec in test_set]))
test_classes.intersection_update(all_classes)
is_valid = len(all_classes) == len(train_classes) == len(test_classes)
print(
f"all_classes = {all_classes}\ntrain_classes = {train_classes}\ntest_classes = {test_classes}\nis_valid = {is_valid}"
)
return is_valid
def persistence(self) -> None:
"""
make the dataset persistent w.r.t. the tranches and the ratios in `self.config`
"""
prev_state = self.__data_aug
_TRANCHES = "ABEF"
if self.training:
ratio = int(self.config.train_ratio * 100)
else:
ratio = 100 - int(self.config.train_ratio * 100)
fn_suffix = f"tranches_{self.tranches or _TRANCHES}_ratio_{ratio}"
if self.config.bandpass is not None:
bp_low = max(0, self.config.bandpass[0])
bp_high = min(self.config.bandpass[1], self.config.fs // 2)
fn_suffix = fn_suffix + f"_bp_{bp_low:.1f}_{bp_high:.1f}"
fn_suffix = fn_suffix + f"_siglen_{self.siglen}"
X, y = [], []
with tqdm(
range(self.__len__()),
total=self.__len__(),
dynamic_ncols=True,
mininterval=1.0,
) as bar:
for idx in bar:
values, labels = self.__getitem__(idx)
X.append(values)
y.append(labels)
X, y = np.array(X), np.array(y)
print(f"X.shape = {X.shape}, y.shape = {y.shape}")
filename = f"{'train' if self.training else 'test'}_X_{fn_suffix}.npy"
np.save(self.reader.db_dir_base / filename, X)
print(f"X saved to {filename}")
filename = f"{'train' if self.training else 'test'}_y_{fn_suffix}.npy"
np.save(self.reader.db_dir_base / filename, y)
print(f"y saved to {filename}")
self.__data_aug = prev_state
def _check_nan(self) -> None:
"""
during training, sometimes nan values are encountered,
which ruins the whole training process
"""
for idx, (values, labels) in self:
if np.isnan(values).any():
print(f"values of {self.records[idx]} have nan values")
if np.isnan(labels).any():
print(f"labels of {self.records[idx]} have nan values")
def extra_repr_keys(self) -> List[str]:
return [
"training",
"tranches",
"reader",
]
class FastDataReader(ReprMixin, Dataset):
""" """
def __init__(
self,
reader: CR,
records: Sequence[str],
config: CFG,
ppm: Optional[PreprocManager] = None,
) -> None:
""" """
self.reader = reader
self.records = records
self.config = config
self.ppm = ppm
if self.config.torch_dtype == torch.float64:
self.dtype = np.float64
else:
self.dtype = np.float32
def __len__(self) -> int:
""" """
return len(self.records)
def __getitem__(self, index: int) -> Tuple[np.ndarray, np.ndarray]:
""" """
rec = self.records[index]
values = self.reader.load_resampled_data(rec, data_format=self.config.data_format, siglen=None)
for idx in range(values.shape[0]):
values[idx] = remove_spikes_naive(values[idx])
if self.ppm:
values, _ = self.ppm(values, self.config.fs)
values = ensure_siglen(
values,
siglen=self.config.input_len,
fmt=self.config.data_format,
tolerance=self.config.sig_slice_tol,
).astype(self.dtype)
if values.ndim == 2:
values = values[np.newaxis, ...]
labels = self.reader.get_labels(rec, scored_only=True, fmt="a", normalize=True)
labels = np.isin(self.config.all_classes, labels).astype(self.dtype)[np.newaxis, ...].repeat(values.shape[0], axis=0)
return values, labels
def extra_repr_keys(self) -> List[str]:
return [
"reader",
"ppm",
]