python3之time模块

时间戳

  1: import time
  2: print(time.time())

可读的时间格式

  1: import time
  2: print(time.ctime())
  3: later = time.time() + 600
  4: print(time.ctime(later))

结果

  1: Wed Jan 30 17:11:49 2019
  2: Wed Jan 30 17:21:49 2019

暂停程序(进程或者线程)

  1: time.sleep(secs)

计时时钟

  1: import time
  2: start = time.monotonic()
  3: time.sleep(0.1)
  4: end = time.monotonic()
  5: print("start:", start)
  6: print("end:", end)
  7: print("span:", end - start)

结果

  1: start: 18363.609
  2: end: 18363.718
  3: span: 0.10900000000037835

处理器时钟时间

反应的是程序运行实际使用的时间

  1: time.clock()

组成时间格式

time模块定义struct_time来保存日期和时间值。

gmtime()函数以UTC格式返回当前时间。localtime应用当前时区的当前时间。mktime取一个实例转化为时间戳浮点数。

  1: import time
  2: print(time.gmtime())
  3: print(time.gmtime().tm_mon)
  4: print(time.localtime())
  5: print(time.localtime().tm_yday)
  6: print(time.mktime(time.localtime()))

结果：

  1: time.struct_time(tm_year=2019, tm_mon=1, tm_mday=30, tm_hour=9, tm_min=32, tm_sec=17, tm_wday=2, tm_yday=30, tm_isdst=0)
  2: 1
  3: time.struct_time(tm_year=2019, tm_mon=1, tm_mday=30, tm_hour=17, tm_min=32, tm_sec=17, tm_wday=2, tm_yday=30, tm_isdst=0)
  4: 30
  5: 1548840737.0

解析和格式化时间

函数strptime和strftime可以在时间值的struct_time表示和字符串表示之间转换。

  1: import time
  2: now = time.ctime()
  3: print("now:", now)
  4: parsed = time.strptime(now)
  5: print("parsed time:", parsed)
  6: print(parsed.tm_year, parsed.tm_mon, parsed.tm_mday)
  7: print("formatted time:", time.strftime("%a-%b-%d-%H:%M:%S %Y", parsed))

结果

  1: now: Wed Jan 30 17:42:07 2019
  2: parsed time: time.struct_time(tm_year=2019, tm_mon=1, tm_mday=30, tm_hour=17, tm_min=42, tm_sec=7, tm_wday=2, tm_yday=30, tm_isdst=-1)
  3: 2019 1 30
  4: formatted time: Wed-Jan-30-17:42:07 2019