Merge pull request #123 from ArneBinder/add_negative_coref_relations/…

…max_num_negatives

add parameter `max_num_negatives` to `add_negative_coref_relations()`

src/pie_modules/document/processing/text_pair.py

@@ -196,6 +196,7 @@ def construct_text_document_from_text_pair_coref_document(
 
 def add_negative_coref_relations(
     documents: Iterable[TextPairDocumentWithLabeledSpansAndBinaryCorefRelations],
+    max_num_negatives: Optional[int] = None,
     downsampling_factor: Optional[float] = None,
     random_seed: Optional[int] = None,
     enforce_same_original_doc_id: bool = False,
@@ -276,27 +277,39 @@ def add_negative_coref_relations(
     for rel in positive_rels:
         new_rels2new_docs[rel].binary_coref_relations.append(rel)
 
-    # Downsampling of negatives. This requires positive instances!
-    if downsampling_factor is not None:
-        if len(positive_rels) == 0:
-            raise ValueError(
-                f"downsampling [factor={downsampling_factor}] is enabled, "
-                f"but no positive relations are available to calculate max_num_negative"
-            )
+    if max_num_negatives is None:
+        # Downsampling of negatives. This requires positive instances!
+        if downsampling_factor is not None:
+            if len(positive_rels) == 0:
+                raise ValueError(
+                    f"downsampling [factor={downsampling_factor}] is enabled, "
+                    f"but no positive relations are available to calculate max_num_negatives"
+                )
+
+            max_num_negatives = int(len(positive_rels) * downsampling_factor)
+            if max_num_negatives == 0:
+                logger.warning(
+                    f"downsampling with factor={downsampling_factor} and number of "
+                    f"positive relations={len(positive_rels)} does not produce any negatives"
+                )
+    elif downsampling_factor is not None:
+        raise ValueError(
+            f"setting max_num_negatives [{max_num_negatives}] and [{downsampling_factor}] "
+            f"simultaneously is ambiguous and not allowed"
+        )
+
+    if max_num_negatives is not None:
+        if random_seed is not None:
+            random.seed(random_seed)
+        random.shuffle(negative_rels)
+        negative_rels = negative_rels[:max_num_negatives]
 
-        max_num_negative = int(len(positive_rels) * downsampling_factor)
-        if max_num_negative == 0:
-            logger.warning(
-                f"downsampling with factor={downsampling_factor} and number of "
-                f"positive relations={len(positive_rels)} does not produce any negatives"
-            )
-        else:
-            if random_seed is not None:
-                random.seed(random_seed)
-            random.shuffle(negative_rels)
-        negative_rels = negative_rels[:max_num_negative]
     for rel in negative_rels:
         new_rels2new_docs[rel].binary_coref_relations.append(rel)
 
     docs_with_rels = [doc for doc in new_docs if len(doc.binary_coref_relations) > 0]
+    logger.info(
+        f"constructed {len(negative_rels)} negative for {len(positive_rels)} "
+        f"positive relations in {len(docs_with_rels)} documents"
+    )
     return docs_with_rels

tests/document/processing/test_text_pair.py

@@ -435,7 +435,7 @@ def test_construct_negative_documents_with_downsampling(positive_documents, capl
     assert (
         str(e.value)
         == "downsampling [factor=1.0] is enabled, but no positive relations are available to calculate "
-        "max_num_negative"
+        "max_num_negatives"
     )