fastNLP/fastNLP/core/callbacks/utils.py

from typing import Optional
from fastNLP.core.log.logger import logger
from difflib import SequenceMatcher


def _get_monitor_value(monitor: str, real_monitor: Optional[str], res: dict) ->(str, float):
    """
    从res中寻找 monitor 并返回。如果 monitor 没找到则尝试用 _real_monitor ,若 _real_monitor 为 None 则尝试使用 monitor 的值进行
        匹配。

    :param monitor:
    :param real_monitor:
    :param res:
    :return: 返回两个值（str, value)，其中str就是最终要到的key，value就是这个key对应的value
    """
    if len(res)==0:
        return monitor, 0

    if monitor in res:
        return monitor, res[monitor]

    if real_monitor in res:
        return real_monitor, res[real_monitor]

    pairs = []
    for idx, (key, value) in enumerate(res.items()):
        match_size = _match_length(monitor, key)
        pairs.append((key, value, match_size, idx))

    pairs.sort(key=lambda pair: (pair[2], -pair[3]), reverse=True)
    key, value, match_size = pairs[0][:3]

    return key, value


def _match_length(a:str, b:str)->int:
    """
    需要把长度短的放在前面

    :param a:
    :param b:
    :return:
    """
    short = a if len(a) < len(b) else b
    long = a if len(a)>=len(b) else b
    match = SequenceMatcher(None, short, long).find_longest_match(0, len(short), 0, len(long))
    return match.size