def _fit_models(self, learn_files, fold_id_bias):
"""
Train models for each algorithm and learn dataset(folds). Than return them.
Args:
:param learn_files: Entities of FoldStorage for learning models.
:return: Dictionary of models where the key is case and the value is models on learn folds
"""
make_dirs_if_not_exists(FoldModelsHandler.__MODEL_DIR)
models = {}
for case in self._cases:
models[case] = list()
for file_num, learn_file in enumerate(learn_files):
pool = FoldModelsHandler._create_pool(learn_file,
self._thread_count)
fold_id = fold_id_bias + file_num
for case in self._cases:
model_path = os.path.join(
FoldModelsHandler.__MODEL_DIR,
FoldModelsHandler._create_model_name(case, fold_id))
get_eval_logger().debug(
"For model {} on fold #{} path is {}".format(
str(case), fold_id, model_path))
fold_model = self._fit_model(pool, case, fold_id, model_path)
get_eval_logger().info(
"Model {} on fold #{} was fitted".format(
str(case), fold_id))
models[case].append(fold_model)
return models
def proceed(self, splitter, fold_size, folds_count, fold_offset):
"""
Run all processes to gain stats. It applies algorithms to fold files that gains from learning. It keeps
stats inside models and models are stored in DataFrame. Columns are matched to the different algos and rows to
the folds.
Args:
:param splitter: Splitter entity.
:param fold_size: The size of fold.
:param folds_count: Count of golds.
:param fold_offset: The offset (count of folds that we want to skip).
:return: return dict: keys metric to CaseEvaluationResult
"""
try:
folds_sets = splitter.create_fold_sets(fold_size, folds_count)
fold_groups_files = splitter.fold_groups_files_generator(
folds_sets, fold_offset)
fold_id_bias = fold_offset
for learn_folds, skipped_folds, rest_folds in fold_groups_files:
if len(learn_folds) == 0:
continue
list_models = []
try:
permutation_models = self._fit_models(
learn_folds, fold_id_bias)
for case, case_models in permutation_models.items():
list_models += case_models
learn_folds_count = len(learn_folds)
get_eval_logger().info(
"Start metric computation for folds [{}, {})".format(
fold_id_bias, fold_id_bias + learn_folds_count))
self._compute_metrics(self._metrics, permutation_models,
learn_folds, skipped_folds,
rest_folds)
get_eval_logger().info(
"Computation of metrics for folds [{}, {}) is completed"
.format(fold_id_bias,
fold_id_bias + learn_folds_count))
fold_id_bias += learn_folds_count
finally:
# Do it each step because don't want to occupy a lot of memory
splitter.clean_folds()
self._remove_models(list_models)
finally:
# Also sometimes we need to remove models and always need to try to remove folds directory.
self._clean(splitter)
return self._case_results
def remove_dir():
"""
Remove default directory for folds if there're no files nut models. In other way it raises warning.
Args:
:return: Nothing.
"""
try:
if os.path.exists(_FoldFile.default_dir):
os.rmdir(_FoldFile.default_dir)
except OSError as err:
get_eval_logger().warning(err.message)
def _remove_model_dir():
try:
if os.path.exists(FoldModelsHandler.__MODEL_DIR):
os.rmdir(FoldModelsHandler.__MODEL_DIR)
except OSError as err:
get_eval_logger().warning(str(err))
def _remove_models(list_models):
get_eval_logger().debug('Remove models {}'.format(str(list_models)))
for model in list_models:
model.delete()
class FoldModelsHandler(object):
"""
Class that is responsible for learning models and computing their metrics
"""
"""
All models are placed to the default directory "models".
"""
__MODEL_DIR = 'models'
@staticmethod
def _remove_model_dir():
try:
if os.path.exists(FoldModelsHandler.__MODEL_DIR):
os.rmdir(FoldModelsHandler.__MODEL_DIR)
except OSError as err:
get_eval_logger().warning(str(err))
def __init__(self, metrics, cases, thread_count, eval_step, remove_models):
"""
Args:
:param remove_models: Set true if you want models to be removed after applying them.
"""
self._cases = cases
self._metrics = metrics
self._case_results = dict()
for case in self._cases:
self._case_results[case] = dict()
self._thread_count = thread_count
self._eval_step = eval_step
self._flag_remove_models = remove_models
self._metric_descriptions = None
def _init_case_results(self, metric_descriptions):
self._metric_descriptions = metric_descriptions
for case in self._cases:
case_result = self._case_results[case]
for metric_description in self._metric_descriptions:
case_result[metric_description] = CaseEvaluationResult(
case, metric_description, eval_step=self._eval_step)
def _compute_metrics(self, metrics, grouped_by_case_models, learn_folds,
skipped_folds, rest_folds):
metric_calcers = {}
for case, case_models in grouped_by_case_models.items():
metric_calcers[case] = list()
for case_model in case_models:
metric_calcer = case_model.create_metrics_calcer(
metrics,
eval_step=self._eval_step,
thread_count=self._thread_count)
metric_calcers[case].append(metric_calcer)
if self._metric_descriptions is None:
self._init_case_results(
metric_calcer.metric_descriptions())
elif self._metric_descriptions != metric_calcer.metric_descriptions(
):
raise CatboostError(
"Error: metric names should be consistent")
for file_num, fold_file in enumerate(learn_folds + skipped_folds +
rest_folds):
pool = FoldModelsHandler._create_pool(fold_file,
self._thread_count)
for case, case_models in grouped_by_case_models.items():
calcers = metric_calcers[case]
for model_num, model in enumerate(case_models):
if file_num != model_num:
calcers[model_num].add(pool)
for case, case_models in grouped_by_case_models.items():
calcers = metric_calcers[case]
case_results = self._case_results[case]
for calcer, model in zip(calcers, case_models):
scores = calcer.eval_metrics()
for metric in self._metric_descriptions:
case_results[metric]._add(model, scores.get_result(metric))
@staticmethod
def _fit_model(pool, case, fold_id, model_path):
from catboost import CatBoost
# Learn model
make_dirs_if_not_exists(FoldModelsHandler.__MODEL_DIR)
get_eval_logger().debug('Learn model {} on fold #{}'.format(
str(case), fold_id))
cur_time = time.time()
instance = CatBoost(params=case.get_params())
instance.fit(pool)
instance.save_model(fname=model_path)
get_eval_logger().debug(
'Operation was done in {} seconds'.format(time.time() - cur_time))
return FoldModel(case, model_path, fold_id)
