# ******************************************************************************
# Copyright 2017-2018 Intel Corporation
#
# 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.
# ******************************************************************************
from nlp_architect.models.absa.inference.data_types import Polarity
from nlp_architect.models.absa.train.data_types import (
CandidateTerm,
RelCategory,
DepRelationTerm,
POS,
)
[docs]def rule_1(dep_rel, gov_entry, dep_entry, text):
"""Extract term if rule 1 applies.
Args:
dep_rel (DepRelation): Dependency relation.
gov_entry (DicEntrySentiment): Governor opinion entry.
dep_entry (DicEntrySentiment): Dependant opinion entry.
text (str): Sentence text.
"""
candidate = None
(anchor_entry, anchor, related) = (
(gov_entry, dep_rel.gov, dep_rel.dep)
if gov_entry
else (dep_entry, dep_rel.dep, dep_rel.gov)
)
if related.norm_pos == POS.ADJ and dep_rel.rel.startswith("conj"):
polarity = anchor_entry.polarity
candidate = CandidateTerm(related, anchor, text, polarity)
return candidate
[docs]def rule_2(dep_rel, relation_list, dep_entry, text):
"""Extract term if rule 2 applies.
Args:
dep_rel (DepRelation): Dependency relation.
relation_list (list of DepRelation): Generic relations between all tokens.
dep_entry (OpinionTerm): Dependent token.
text (str): Sentence text.
"""
candidate = None
for curr_rt in relation_list:
if (curr_rt.gov, curr_rt.rel, curr_rt.dep.norm_pos) == (
dep_rel.gov,
dep_rel.rel,
POS.ADJ,
) and curr_rt.dep != dep_rel.dep:
candidate = CandidateTerm(curr_rt.dep, dep_rel.dep, text, dep_entry.polarity)
return candidate
[docs]def rule_3(dep_rel, relation_list, text):
"""Extract term if rule 3 applies.
Args:
dep_rel (DepRelation): Dependency relation.
relation_list (list of DepRelation): Generic relations between all tokens.
text (str): Sentence text.
"""
candidate = None
if dep_rel.gov.norm_pos == POS.NN and is_subj_obj_or_mod(dep_rel):
aspect = expand_aspect(dep_rel.gov, relation_list)
candidate = CandidateTerm(aspect, dep_rel.dep, text, Polarity.UNK)
return candidate
[docs]def rule_4(dep_rel, relation_list, text):
"""Extract term if rule 4 applies.
Args:
dep_rel (DepRelation): Dependency relation.
relation_list (list of DepRelation): Generic relations between all tokens.
relation between tokens
text (str): Sentence text.
"""
candidate = None
for curr_rt in relation_list:
if (
curr_rt.gov == dep_rel.gov
and curr_rt.dep != dep_rel.dep
and curr_rt.dep.norm_pos == POS.NN
and is_subj_obj_or_mod(curr_rt)
and is_subj_obj_or_mod(dep_rel)
):
aspect = expand_aspect(curr_rt.dep, relation_list)
candidate = CandidateTerm(aspect, dep_rel.dep, text, Polarity.UNK)
return candidate
[docs]def rule_5(dep_rel, text):
"""Extract term if rule 5 applies.
Args:
dep_rel (DepRelation): Dependency relation.
text (str): Sentence text.
"""
candidate = None
if is_subj_obj_or_mod(dep_rel) and dep_rel.dep.norm_pos == POS.ADJ:
return CandidateTerm(dep_rel.dep, dep_rel.gov, text, Polarity.UNK)
return candidate
[docs]def rule_6(dep_rel, relation_list, text):
"""Extract term if rule 6 applies.
Args:
dep_rel (DepRelation): Dependency relation.
relation_list (list of DepRelation): Generic relations between all tokens.
text (str): Sentence text.
"""
candidate = None
if dep_rel.rel.startswith("conj") and dep_rel.dep.norm_pos in {
POS.ADJ,
POS.ADV,
POS.NN,
POS.VB,
}:
aspect = expand_aspect(dep_rel.dep, relation_list)
candidate = CandidateTerm(aspect, dep_rel.gov, text, Polarity.UNK)
return candidate
[docs]def is_subj_obj_or_mod(rt):
return any(rt.rel in cat.value for cat in (RelCategory.SUBJ, RelCategory.OBJ, RelCategory.MOD))
[docs]def expand_aspect(in_aspect_token, relation_list):
"""Expand aspect by Looking for a noun word that its gov is the aspect. if it has (noun)
compound relation add it to aspect."""
aspect = DepRelationTerm(
text=in_aspect_token.text,
lemma=in_aspect_token.lemma,
pos=in_aspect_token.pos,
ner=in_aspect_token.ner,
idx=in_aspect_token.idx,
)
for rel in relation_list:
if (rel.rel == "compound") and (rel.gov.idx == aspect.idx):
diff_positive = aspect.idx - len(rel.dep.text) - 1 - rel.dep.idx
diff_negative = rel.dep.idx - len(aspect.text) - 1 - aspect.idx
if diff_positive == 0:
aspect.text = rel.dep.text + " " + aspect.text
aspect.lemma = rel.dep.text + " " + aspect.lemma
aspect.idx = rel.dep.idx
if diff_negative == 0:
aspect.text = aspect.text + " " + rel.dep.text
aspect.lemma = aspect.lemma + " " + rel.dep.lemma
aspect.text = aspect.text.lower()
aspect.lemma = aspect.lemma.lower()
return aspect