LLaMA-Factory/src/utils/seq2seq.py
hiyouga 7ea072536b fix eval and pred loss
Former-commit-id: c30db9f1f0db5a6a660cdc60016755241762aae7
2023-07-14 13:11:57 +08:00

117 lines
4.5 KiB
Python

import os
import json
import torch
import numpy as np
import torch.nn as nn
from dataclasses import dataclass
from typing import Any, Dict, List, Optional, 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": []}
preds = np.where(preds != IGNORE_INDEX, preds, self.tokenizer.pad_token_id)
labels = np.where(labels != IGNORE_INDEX, labels, self.tokenizer.pad_token_id)
decoded_preds = self.tokenizer.batch_decode(preds, skip_special_tokens=True)
decoded_labels = self.tokenizer.batch_decode(labels, skip_special_tokens=True)
for pred, label in zip(decoded_preds, decoded_labels):
hypothesis = list(jieba.cut(pred))
reference = list(jieba.cut(label))
if len(" ".join(hypothesis).split()) == 0 or len(" ".join(reference).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 prediction_step(
self,
model: nn.Module,
inputs: Dict[str, Union[torch.Tensor, Any]],
prediction_loss_only: bool,
ignore_keys: Optional[List[str]] = None,
) -> Tuple[Optional[float], Optional[torch.Tensor], Optional[torch.Tensor]]:
r"""
Removes the prompt part in the generated tokens.
Subclass and override to inject custom behavior.
"""
prompt_len, label_len = inputs["input_ids"].size(-1), inputs["labels"].size(-1)
inputs["labels"] = torch.cat((inputs["labels"], torch.zeros_like(inputs["input_ids"])[:, label_len:]), dim=-1)
loss, generated_tokens, labels = super().prediction_step(
model, inputs, prediction_loss_only=prediction_loss_only, ignore_keys=ignore_keys
)
generated_tokens = generated_tokens[:, prompt_len:] if generated_tokens is not None else None
return (loss, generated_tokens, labels)
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}")
preds = np.where(predict_results.predictions != IGNORE_INDEX, predict_results.predictions, self.tokenizer.pad_token_id)
labels = np.where(predict_results.label_ids != IGNORE_INDEX, predict_results.label_ids, self.tokenizer.pad_token_id)
decoded_preds = self.tokenizer.batch_decode(preds, skip_special_tokens=True, clean_up_tokenization_spaces=True)
decoded_labels = self.tokenizer.batch_decode(labels, skip_special_tokens=True, clean_up_tokenization_spaces=True)
with open(output_prediction_file, "w", encoding="utf-8") as writer:
res: List[str] = []
for pred, label in zip(decoded_preds, decoded_labels):
res.append(json.dumps({"label": label, "predict": pred}, ensure_ascii=False))
writer.write("\n".join(res))