kenlm / model.py
edugp's picture
Add model card with sample usage
13451d2
raw history blame
No virus
4.62 kB
import os
import re
import unicodedata
from typing import Dict
import kenlm
import sentencepiece
from huggingface_hub import cached_download, hf_hub_url
class SentencePiece:
def __init__(
self,
model: str,
):
super().__init__()
self.sp = sentencepiece.SentencePieceProcessor()
self.sp.load(str(model))
def do(self, text: dict) -> dict:
tokenized = self.sp.encode_as_pieces(text)
return " ".join(tokenized)
class KenlmModel:
digit_re: re.Pattern = re.compile(r"\d")
unicode_punct: Dict[str, str] = {
",": ",",
"。": ".",
"、": ",",
"„": '"',
"”": '"',
"“": '"',
"«": '"',
"»": '"',
"1": '"',
"」": '"',
"「": '"',
"《": '"',
"》": '"',
"´": "'",
"∶": ":",
":": ":",
"?": "?",
"!": "!",
"(": "(",
")": ")",
";": ";",
"–": "-",
"—": " - ",
".": ". ",
"~": "~",
"’": "'",
"…": "...",
"━": "-",
"〈": "<",
"〉": ">",
"【": "[",
"】": "]",
"%": "%",
"►": "-",
}
unicode_punct_re = re.compile(f"[{''.join(unicode_punct.keys())}]")
non_printing_chars_re = re.compile(
f"[{''.join(map(chr, list(range(0,32)) + list(range(127,160))))}]"
)
kenlm_model_dir = None
sentence_piece_model_dir = None
def __init__(
self,
model_dataset: str,
language: str,
lower_case: bool = False,
remove_accents: bool = False,
normalize_numbers: bool = True,
punctuation: int = 1,
):
self.model = kenlm.Model(os.path.join(model_dataset, f"{language}.arpa.bin"))
self.tokenizer = SentencePiece(os.path.join(model_dataset, f"{language}.sp.model"))
self.accent = remove_accents
self.case = lower_case
self.numbers = normalize_numbers
self.punct = punctuation
@classmethod
def from_pretrained(
cls,
model_dataset: str,
language: str,
):
return cls(
model_dataset,
language,
False,
False,
True,
1,
)
def pp(self, log_score, length):
return 10.0 ** (-log_score / length)
def get_perplexity(self, doc: str, normalize_cc_net: bool = True):
if normalize_cc_net:
doc = self.normalize(
doc,
accent=self.accent,
case=self.case,
numbers=self.numbers,
punct=self.punct,
)
# Tokenize (after normalizing): See https://github.com/facebookresearch/cc_net/blob/bda555bd1cf1ee2e0b925363e62a61cd46c8b60d/cc_net/mine.py#L352 for full pipeline
doc = self.tokenizer.do(doc)
doc_log_score, doc_length = 0, 0
for line in doc.split("\n"):
log_score = self.model.score(line)
length = len(line.split()) + 1
doc_log_score += log_score
doc_length += length
return round(self.pp(doc_log_score, doc_length), 1)
def normalize(
self,
line: str,
accent: bool = True,
case: bool = True,
numbers: bool = True,
punct: int = 1,
) -> str:
line = line.strip()
if not line:
return line
if case:
line = line.lower()
if accent:
line = self.strip_accents(line)
if numbers:
line = self.digit_re.sub("0", line)
if punct == 1:
line = self.replace_unicode_punct(line)
elif punct == 2:
line = self.remove_unicode_punct(line)
line = self.remove_non_printing_char(line)
return line
def strip_accents(self, line: str) -> str:
"""Strips accents from a piece of text."""
nfd = unicodedata.normalize("NFD", line)
output = [c for c in nfd if unicodedata.category(c) != "Mn"]
if len(output) == line:
return line
return "".join(output)
def replace_unicode_punct(self, text: str) -> str:
return "".join(self.unicode_punct.get(c, c) for c in text)
def remove_unicode_punct(self, text: str) -> str:
"""More aggressive version of replace_unicode_punct but also faster."""
return self.unicode_punct_re.sub("", text)
def remove_non_printing_char(self, text: str) -> str:
return self.non_printing_chars_re.sub("", text)