def _get_any_merge_candidate(self, t1: Template,
t2: Template) -> MergeCandidate:
""" Unused version of _get_best_merge_candidate, but might be prefered for performance gains """
max_length = max(t1.get_number_of_non_slots(),
t2.get_number_of_non_slots())
min_slots = min(t1.get_number_of_slots(), t2.get_number_of_slots())
merged_template = next(
Template.merge_templates_wagner_fischer(
t1, t2, minimal_variables=self._minimal_variables))
return MergeCandidate(
t1, t2,
_get_distance_of_merged(merged_template, max_length, min_slots))
def _get_best_merge_candidate(self, t1: Template,
t2: Template) -> MergeCandidate:
"""
Calculates the distance between two given templates, that can contain slots
"""
max_length = max(t1.get_number_of_non_slots(),
t2.get_number_of_non_slots())
min_slots = min(t1.get_number_of_slots(), t2.get_number_of_slots())
merged_templates = set(
Template.merge_templates_wagner_fischer(
t1, t2, minimal_variables=self._minimal_variables))
merge_candidates = []
for merged_template in merged_templates:
distance = _get_distance_of_merged(merged_template, max_length,
min_slots)
merge_candidates.append(
MergeCandidate(t1, t2, distance, merged=merged_template))
return min(merge_candidates)
def _get_distance_of_merged(merged_template: Template, max_length: int,
min_slots: int) -> int:
length_diff = max_length - merged_template.get_number_of_non_slots()
slot_diff = merged_template.get_number_of_slots() - min_slots
return length_diff + slot_diff