Datasets:

inseq
/

scat

	"""Script used to filter malformed examples from the original SCAT corpus.

	To run, copy original SCAT files from https://github.com/neulab/contextual-mt/tree/master/data/scat under the same
	path of the script. Filtered files will be created in the filtered_scat folder.

	Uncomment lines to save dropped malformed sentences into separate files for inspection.
	"""

	import re
	from pathlib import Path

	def drop_malformed_tags(
	split: str,
	save_folder: str = "filtered_scat",
	):
	find_tag_pattern = r"(<hon>\|<\/?p>\|<hoff>)"
	nested_uninformative_pattern = r"(<hon>\W(<p>[^<]</p>)\W*<hoff>)"
	embedded_tag = r"\s(\S+<p>[^<]</p>\S\|\S<p>[^<]</p>\S+)\s"

	with open(f"highlighted.{split}.context.en") as f:
	orig_ctx_en = f.readlines()
	with open(f"highlighted.{split}.context.fr") as f:
	orig_ctx_fr = f.readlines()
	with open(f"highlighted.{split}.en") as f:
	orig_tgt_en = f.readlines()
	with open(f"highlighted.{split}.fr") as f:
	orig_tgt_fr = f.readlines()

	print("# of context examples: EN -", len(orig_ctx_en), "FR -", len(orig_ctx_fr))
	print("# of target examples: EN -", len(orig_tgt_en), "FR -", len(orig_tgt_fr))

	ctx_en = []
	ctx_fr = []
	tgt_en = []
	tgt_fr = []

	drop_ctx_en = []
	drop_ctx_fr = []
	drop_tgt_en = []
	drop_tgt_fr = []

	for ex_idx in range(len(orig_ctx_en)):
	drop = False
	txt_list = [orig_ctx_en[ex_idx], orig_tgt_en[ex_idx], orig_ctx_fr[ex_idx], orig_tgt_fr[ex_idx]]

	# Drop malformed <p>...</p> tags in which random mid-word spans are tagged
	# e.g. "I bought a picture frame for my desk, and <p>it</p>'s just s<p>it</p>ting there, wa<p>it</p>ing for his face."
	for i in range(len(txt_list)):
	for embedded_tag_match in re.findall(embedded_tag, txt_list[i]):
	removed_tag = embedded_tag_match.replace("<p>", "").replace("</p>", "")
	txt_list[i] = txt_list[i].replace(embedded_tag_match, removed_tag, 1)

	# <p>...</p> tags should only be present in the target text
	if not (
	"<p>" in txt_list[1] and "</p>" in txt_list[1] and "<p>" in txt_list[3] and "</p>" in txt_list[3] and
	"<p>" not in txt_list[0] and "</p>" not in txt_list[0] and "<p>" not in txt_list[2] and "</p>" not in txt_list[2]
	):
	drop = True

	# Nested tags like <hon><p>it</p><hoff> are uninformative and simply mean the supporting context wasn't found
	# in the source. We replace them with the inner tag <p>it</p> so that the tag is dropped for the next step.
	for i in range(len(txt_list)):
	for uninformative_match, nested_tag in re.findall(nested_uninformative_pattern, txt_list[i]):
	txt_list[i] = txt_list[i].replace(uninformative_match, nested_tag, 1)
	txt = " ".join(txt_list)

	matches = [(m.group(0),) + m.span() for m in re.finditer(find_tag_pattern, txt)]

	if not drop:
	if len(matches) > 0 and len(matches) % 2 == 0:
	for match_idx in range(0, len(matches), 2):

	if not (
	(matches[match_idx][0] == "<hon>" and matches[match_idx+1][0] == "<hoff>") or
	(matches[match_idx][0] == "<p>" and matches[match_idx+1][0] == "</p>") or
	(matches[match_idx][2] < matches[match_idx+1][1])
	):
	drop = True
	break
	else:
	drop = True
	if not drop:
	ctx_en.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[0].strip())) + "\n")
	ctx_fr.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[2].strip())) + "\n")
	tgt_en.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[1].strip())) + "\n")
	tgt_fr.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[3].strip())) + "\n")

	else:
	drop_ctx_en.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[0].strip())) + "\n")
	drop_ctx_fr.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[2].strip())) + "\n")
	drop_tgt_en.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[1].strip())) + "\n")
	drop_tgt_fr.append(re.sub(r"\u200e", "", re.sub(r"\u200b", "", txt_list[3].strip())) + "\n")
	#print("Dropped example:", txt)

	print("# of dropped examples:", len(orig_ctx_en) - len(ctx_en))
	print("# of filtered examples:", len(ctx_en))

	save_folder = Path(save_folder)
	save_folder.mkdir(parents=True, exist_ok=True)
	with open(save_folder / f"filtered.{split}.context.en", "w") as f:
	f.writelines(ctx_en)
	with open(save_folder / f"filtered.{split}.context.fr", "w") as f:
	f.writelines(ctx_fr)
	with open(save_folder / f"filtered.{split}.en", "w") as f:
	f.writelines(tgt_en)
	with open(save_folder / f"filtered.{split}.fr", "w") as f:
	f.writelines(tgt_fr)

	with open(save_folder / f"dropped.{split}.context.en", "w") as f:
	f.writelines(drop_ctx_en)
	with open(save_folder / f"dropped.{split}.context.fr", "w") as f:
	f.writelines(drop_ctx_fr)
	with open(save_folder / f"dropped.{split}.en", "w") as f:
	f.writelines(drop_tgt_en)
	with open(save_folder / f"dropped.{split}.fr", "w") as f:
	f.writelines(drop_tgt_fr)

	print("Files written to the filtered_scat folder")


	if __name__ == "__main__":
	drop_malformed_tags("train")
	drop_malformed_tags("valid")
	drop_malformed_tags("test")