python生成时间序列(date_range)
python生成时间序列(date_range)
介绍
自己写了一个用python内置模块实现的生成时间序列的函数
支持自动推断字符串到datetime的转换, 但对格式有一定要求, 其它格式可手动指定格式化方式, 格式化方式与python内置格式化格式完全一致
支持输出格式化
以下是方法的源代码(python环境3.5以上, 没做更多版本的支持, 需要的自己稍作调整即可)
源代码
import re import calendar import datetime class FormatError(ValueError): pass class Date(object): @classmethod def date_range(cls, start=None, end=None, periods=None, freq=None, input_format=None, out_format=None): """ 生成时间序列 :param start: 序列开始时间 :param end: 序列结束时间, 给定start时, 结束时间不包含end :param periods: int, 生成的时间序列长度 :param freq: 要生成时间序列的时间间隔 :param out_format: 是否输出格式化后的字符串, 若要输出可指定输出格式. "%Y-%m-%d %H:%M:%S" :param input_format: 若start或end是字符串且无法自动推断时间格式则需指定格式 :return: [date or date_str] """ start = cls.str_to_date(start, input_format) end = cls.str_to_date(end, input_format) out = [] if start is None and end and periods: for i in range(periods-1): old, end = cls.date_replace(end, cls._freq(freq), mod="-") if i == 0: out.append(old) out = [end] + out elif end is None and start and periods: for i in range(periods-1): old, start = cls.date_replace(start, cls._freq(freq), mod="+") if i == 0: out.append(old) out.append(start) elif periods is None and start and end: i = 0 while True: old, start = cls.date_replace(start, cls._freq(freq), mod="+") if i == 0: out.append(old) i += 1 if start < end: out.append(start) else: break else: raise ValueError("start, end, periods 须且只能指定其中两个") if out_format is True: out = [str(i) for i in out] elif out_format is not None: out = [i.strftime(out_format) for i in out] return out @staticmethod def date_replace(date, freq=(0, )*6, mod="+"): timedelta = datetime.timedelta(days=freq[2], hours=freq[3], minutes=freq[4], seconds=freq[5]) if mod == "+": if sum(freq[:2]) == 0: old = date date = date + timedelta elif sum(freq[2:]) == 0: y = date.year + freq[0] + (date.month + freq[1] - 1) // 12 m = (date.month + freq[1] - 1) % 12 + 1 old = date.replace(day=calendar.monthrange(date.year, date.month)[1]) date = date.replace(year=y, month=m, day=calendar.monthrange(y, m)[1]) else: raise ValueError(" '年月' 不能同时和 '日时分秒' 作为间隔") elif mod == "-": if sum(freq[:2]) == 0: old = date date = date - timedelta elif sum(freq[2:]) == 0: y = date.year - freq[0] + (date.month - freq[1] - 1) // 12 m = (date.month - freq[1] - 1) % 12 + 1 old = date.replace(day=calendar.monthrange(date.year, date.month)[1]) date = date.replace(year=y, month=m, day=calendar.monthrange(y, m)[1]) else: raise ValueError(" '年月' 不能同时和 '日时分秒' 作为间隔") else: raise ValueError("mod值只能是 '+' 或 '-' ") return old, date @staticmethod def _freq(freq=None): """ 设置时间间隔 :param freq: "Y2m3d4H5M6S" 表示间隔 1年2月3日4时5分6秒 :return: [年, 月, 日, 时, 分, 秒] """ freq_ = [0] * 6 if freq is None: freq_[2] = 1 return freq_ for n, i in enumerate(["Y", "m", "d", "H", "M", "S"]): r = f'((\d*){i})' s = re.search(r, freq) if s: freq_[n] = int(s.group(2)) if s.group(2) else 1 return freq_ @staticmethod def str_to_date(string, format_=None): """ 字符串转时间, 默认自动推断格式 :param string: 时间字符串 :param format_: 格式 :return: 对应的时间类型, 输入非字符串则原值输出 """ if not isinstance(string, str): return string if format_: return datetime.datetime.strptime(string, format_) s = re.match(r'(\d{4})\D+(\d{1,2})\D+(\d{1,2})(?:\D+(\d{1,2}))?(?:\D+(\d{1,2}))?(?:\D+(\d{1,2}))?\D*$', string) if s: result = [int(i) for i in s.groups() if i] return datetime.datetime(*result) s = re.match(r'(\d{4})\D*(\d{2})\D*(\d{2})\D*(\d{2})?\D*(\d{2})?\D*(\d{2})?\D*$', string) if s: result = [int(i) for i in s.groups() if i] return datetime.datetime(*result) else: raise FormatError("自动推断失败, 请指定format_")
使用方式
print(Date.date_range(datetime.datetime(2018, 9, 18), periods=10)) print() print(Date.date_range('20180918', '2018-09-28')) print() print(Date.date_range(end='20180927', periods=10)) print() print(Date.date_range('20180918', '2018-09-28', out_format=True)) print() print(Date.date_range('2018/09/18', '2018-09-28', out_format="%Y-%m-%d")) print() print(Date.date_range('2018年9月18日', '2019-09-28', freq="m", out_format="%Y-%m-%d")) print() print(Date.date_range('2018/9/18', '2018-9-19', freq="3H", out_format=True))
对应结果
[datetime.datetime(2018, 9, 18, 0, 0), datetime.datetime(2018, 9, 19, 0, 0), datetime.datetime(2018, 9, 20, 0, 0), datetime.datetime(2018, 9, 21, 0, 0), datetime.datetime(2018, 9, 22, 0, 0), datetime.datetime(2018, 9, 23, 0, 0), datetime.datetime(2018, 9, 24, 0, 0), datetime.datetime(2018, 9, 25, 0, 0), datetime.datetime(2018, 9, 26, 0, 0), datetime.datetime(2018, 9, 27, 0, 0)] [datetime.datetime(2018, 9, 18, 0, 0), datetime.datetime(2018, 9, 19, 0, 0), datetime.datetime(2018, 9, 20, 0, 0), datetime.datetime(2018, 9, 21, 0, 0), datetime.datetime(2018, 9, 22, 0, 0), datetime.datetime(2018, 9, 23, 0, 0), datetime.datetime(2018, 9, 24, 0, 0), datetime.datetime(2018, 9, 25, 0, 0), datetime.datetime(2018, 9, 26, 0, 0), datetime.datetime(2018, 9, 27, 0, 0)] [datetime.datetime(2018, 9, 18, 0, 0), datetime.datetime(2018, 9, 19, 0, 0), datetime.datetime(2018, 9, 20, 0, 0), datetime.datetime(2018, 9, 21, 0, 0), datetime.datetime(2018, 9, 22, 0, 0), datetime.datetime(2018, 9, 23, 0, 0), datetime.datetime(2018, 9, 24, 0, 0), datetime.datetime(2018, 9, 25, 0, 0), datetime.datetime(2018, 9, 26, 0, 0), datetime.datetime(2018, 9, 27, 0, 0)] ['2018-09-18 00:00:00', '2018-09-19 00:00:00', '2018-09-20 00:00:00', '2018-09-21 00:00:00', '2018-09-22 00:00:00', '2018-09-23 00:00:00', '2018-09-24 00:00:00', '2018-09-25 00:00:00', '2018-09-26 00:00:00', '2018-09-27 00:00:00'] ['2018-09-18', '2018-09-19', '2018-09-20', '2018-09-21', '2018-09-22', '2018-09-23', '2018-09-24', '2018-09-25', '2018-09-26', '2018-09-27'] ['2018-09-30', '2018-10-31', '2018-11-30', '2018-12-31', '2019-01-31', '2019-02-28', '2019-03-31', '2019-04-30', '2019-05-31', '2019-06-30', '2019-07-31', '2019-08-31'] ['2018-09-18 00:00:00', '2018-09-18 03:00:00', '2018-09-18 06:00:00', '2018-09-18 09:00:00', '2018-09-18 12:00:00', '2018-09-18 15:00:00', '2018-09-18 18:00:00', '2018-09-18 21:00:00']
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