Cluster Class

Class for coreference cluster.

Attributes

Name	Type	Description
cluster_idx	Integer	Index of the cluster in the document.
spans_idx	List	Indexes of the spans of the cluster.
ref_document	Document	Reference to the Document object
head	Span	Returns the head of a cluster, which is the span that best represent the cluster.
children	List	Returns the children of the cluster, i.e. all spans except head.

cluster_idx

Index of the cluster in the document.

self.spans_idx = spans_idx

spans_idx

Indexes of the spans of the cluster.

self.cluster_idx = cluster_idx

ref_document

Reference to the Document object

self.ref_document = ref_document

head

Returns the head of a cluster, which is the span that best represent the cluster. This is done according to a hierarchy that use the POS tags inside the spans.

Return:

Type	Description
Span	Span of the head of the cluster

hierarchy_pos_cluster = ['NP', ['PD','N'], ['D', 'N'], 'N', 'CLS', 'CLO', 'PRON', 'D', 'PROREL', 'PD', 'P', 'ENTITY'] 

head()

for h in hierarchy_pos_cluster:
    if isinstance(h, list):
        match = [s for s in self.spans if set(h) & set(s.get_attributes('pos')) == set(h)]
    else:
        match = [s for s in self.spans if h in s.get_attributes('pos')]
    if match:
        return match[0]
    return self.spans[0]

children

Returns the children of the cluster, i.e. all spans except head.

Return:

Type	Description
List	List of children spans.

children()

head = self.head
return [span for span in self.spans if span != head]