Files
LLaMA-Factory/src/utils/seq2seq.py
2023-06-27 23:54:24 +08:00

93 lines
3.4 KiB
Python

import os
import json
import numpy as np
from dataclasses import dataclass
from typing import Dict, List, Sequence, Tuple, Union
from transformers.trainer import PredictionOutput
from transformers.tokenization_utils import PreTrainedTokenizer
import jieba
from rouge_chinese import Rouge
from nltk.translate.bleu_score import sentence_bleu, SmoothingFunction
from .peft_trainer import PeftTrainer
from .other import get_logger, IGNORE_INDEX
logger = get_logger(__name__)
@dataclass
class ComputeMetrics:
r"""
Wraps the tokenizer into metric functions, used in Seq2SeqPeftTrainer.
"""
tokenizer: PreTrainedTokenizer
def __call__(self, eval_preds: Sequence[Union[np.ndarray, Tuple[np.ndarray]]]) -> Dict[str, float]:
r"""
Uses the model predictions to compute metrics.
"""
preds, labels = eval_preds
score_dict = {"rouge-1": [], "rouge-2": [], "rouge-l": [], "bleu-4": []}
for pred, label in zip(preds, labels):
pred_pad_len, label_pad_len = np.sum(pred == IGNORE_INDEX), np.sum(label == IGNORE_INDEX)
pred = pred[len(label) - label_pad_len : len(pred) - pred_pad_len] # remove prompts
label = label[:len(label) - label_pad_len]
hypothesis = list(jieba.cut(self.tokenizer.decode(pred, skip_special_tokens=True)))
reference = list(jieba.cut(self.tokenizer.decode(label, skip_special_tokens=True)))
if len(" ".join(hypothesis).split()) == 0:
result = {"rouge-1": {"f": 0.0}, "rouge-2": {"f": 0.0}, "rouge-l": {"f": 0.0}}
else:
rouge = Rouge()
scores = rouge.get_scores(" ".join(hypothesis), " ".join(reference))
result = scores[0]
for k, v in result.items():
score_dict[k].append(round(v["f"] * 100, 4))
bleu_score = sentence_bleu([list(label)], list(pred), smoothing_function=SmoothingFunction().method3)
score_dict["bleu-4"].append(round(bleu_score * 100, 4))
return {k: float(np.mean(v)) for k, v in score_dict.items()}
class Seq2SeqPeftTrainer(PeftTrainer):
r"""
Inherits PeftTrainer to compute generative metrics such as BLEU and ROUGE.
"""
def save_predictions(
self,
predict_results: PredictionOutput
) -> None:
r"""
Saves model predictions to `output_dir`.
A custom behavior that not contained in Seq2SeqTrainer.
"""
if not self.is_world_process_zero():
return
output_prediction_file = os.path.join(self.args.output_dir, "generated_predictions.jsonl")
logger.info(f"Saving prediction results to {output_prediction_file}")
with open(output_prediction_file, "w", encoding="utf-8") as writer:
res: List[str] = []
for pred, label in zip(predict_results.predictions, predict_results.label_ids):
pred_pad_len, label_pad_len = np.sum(pred == IGNORE_INDEX), np.sum(label == IGNORE_INDEX)
pred = pred[len(label) - label_pad_len : len(pred) - pred_pad_len] # remove prompts
label = label[:len(label) - label_pad_len]
pred = self.tokenizer.decode(pred, skip_special_tokens=True)
label = self.tokenizer.decode(label, skip_special_tokens=True)
res.append(json.dumps({"label": label, "predict": pred}, ensure_ascii=False))
writer.write("\n".join(res))