# Copyright 2019-2022 The ASReview Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import logging
from asreview.utils import _model_class_from_entry_point
from asreview.utils import list_model_names
def _set_class_weight(weight1):
"""Used various classifiers to have quicker learning."""
if weight1 is None:
return None
weight0 = 1.0
cw_class = {
0: weight0,
1: weight1,
}
logging.debug(f"Using class weights: 0 <- {weight0}, 1 <- {weight1}")
return cw_class
[docs]def list_classifiers():
"""List available classifier classes.
Returns
-------
list:
Classes of available classifiers in alphabetical order.
"""
model_class = [
get_classifier_class(name)
for name in list_model_names(entry_name="asreview.models.classifiers")
]
return model_class
[docs]def get_classifier_class(name):
"""Get class of model from string.
Arguments
---------
name: str
Name of the model, e.g. 'svm', 'nb' or 'lstm-pool'.
Returns
-------
BaseModel:
Class corresponding to the name.
"""
return _model_class_from_entry_point(name, "asreview.models.classifiers")
[docs]def get_classifier(name, *args, random_state=None, **kwargs):
"""Get an instance of a model from a string.
Arguments
---------
name: str
Name of the model.
*args:
Arguments for the model.
**kwargs:
Keyword arguments for the model.
Returns
-------
BaseFeatureExtraction:
Initialized instance of classifier.
"""
model_class = get_classifier_class(name)
try:
return model_class(*args, random_state=random_state, **kwargs)
except TypeError:
return model_class(*args, **kwargs)