1. Calender

calendar — General calendar-related functions calendar — Work with Dates — PyMOTW 3

Python中的calendar十个无关紧要的工具，没有人会费力不讨好的到这里查看日期和规划日程。

class TextCalendar(Calendar)
 |  TextCalendar(firstweekday=0)
In [326]: cal = calendar.TextCalendar(calendar.MONDAY)       #周一作为一周的起始点
In [327]: cal.prmonth(2019, 5)
      May 2019
Mo Tu We Th Fr Sa Su
       1  2  3  4  5
 6  7  8  9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31
In [328]: cal.pryear(2019)
                                  2019
      January                                   February                                    March
Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
    1  2  3  4  5  6                   1  2  3                                           1  2  3
 7  8  9 10 11 12 13           4  5  6  7  8  9 10                            4  5  6  7  8  9 10
14 15 16 17 18 19 20      11 12 13 14 15 16 17              11 12 13 14 15 16 17
21 22 23 24 25 26 27      18 19 20 21 22 23 24             18 19 20 21 22 23 24
28 29 30 31                       25 26 27 28                                  25 26 27 28 29 30 31
# 只了解下TextCalendar, pryear, prmonth

2. Time

time — Time access and conversions calendar — Work with Dates — PyMOTW 3

• 与epoch time的相互转换

  Use the following functions to convert between time representations: 人以minutes计时， 机器以second计时。

  From	To	Use
  seconds since the epoch	`struct_time <htt ps://docs.python.org/ 3/library/time.html#t ime.struct_time>`__ in UTC	`gmtime() <https: //docs.python.org/3/l ibrary/time.html#time .gmtime>`__
  seconds since the epoch	`struct_time <htt ps://docs.python.org/ 3/library/time.html#t ime.struct_time>`__ in local time	`localtime() <htt ps://docs.python.org/ 3/library/time.html#t ime.localtime>`__
  `struct_time <htt ps://docs.python.org/ 3/library/time.html#t ime.struct_time>`__ in UTC	seconds since the epoch	``calendar.timegm() ` <https://docs.pytho n.org/3/library/calen dar.html#calendar.tim egm>`__ System Message: WARNING/2 (<string>, line 120); backlink Inline literal start-string without end-string.
  `struct_time <htt ps://docs.python.org/ 3/library/time.html#t ime.struct_time>`__ in local time	seconds since the epoch	`mktime() <https: //docs.python.org/3/l ibrary/time.html#time .mktime>`__

  #seconds to  timetuple
  In [8]: time.localtime() #local time
  Out[8]: time.struct_time(tm_year=2019, tm_mon=5, tm_mday=15, tm_hour=20, tm_min=4, tm_sec=17, tm_wday=2, tm_yday=135, tm_isdst=0)
  
  In [9]: time.gmtime() #UTC time
  Out[9]: time.struct_time(tm_year=2019, tm_mon=5, tm_mday=15, tm_hour=12, tm_min=4, tm_sec=31, tm_wday=2, tm_yday=135, tm_isdst=0)
  
  In [11]: time.gmtime(100)  #
  Out[11]: time.struct_time(tm_year=1970, tm_mon=1, tm_mday=1, tm_hour=0, tm_min=1, tm_sec=40, tm_wday=3, tm_yday=1, tm_isdst=0)
  #timetuple to seconds
  In [17]: calendar.timegm(time.gmtime()) #UTC time
  Out[17]: 1557922318
  In [18]: time.mktime(time.localtime()) #Local time
  Out[18]: 1557922368.0

• 第十一个-时间变量 tm_isdst daylight saving time夏季时间

  gmtime(...) ->time.struct_time,  (strptime, localtime)
      gmtime([seconds]) -> (tm_year, tm_mon, tm_mday, tm_hour, tm_min,
                             tm_sec, tm_wday, tm_yday, tm_isdst)
  

• Processor Time and Timer

  time.process_time() #cpu time  of kernel and user-space
  time.process_time_ns() ->int #not inclue sleep time
  time.perf_counter() ->float
  time.perf_counter_ns() -> int
  time.thread_time() ->float
  time.thread_time_ns() ->int
  time.time()
  time.time_ns()
  time.sleep
  time.monotonic()
  time.monotonic_ns()
  

• Timezone Constants

  In [9]: time.daylight
  Out[9]: 0
  In [10]: time.tzname
  Out[10]: ('CST', 'CST')
  In [11]: time.altzone
  Out[11]: -28800
  

• 两个重要的methods

  time.strptime(string, format)
  time.strftime(format)
  

• ctime

  In [20]: time.asctime(time.localtime())
  Out[20]: 'Wed May 15 21:05:27 2019'
  In [21]: time.ctime()
  Out[21]: 'Wed May 15 21:05:32 2019'
  

3. Datetime

复习calendar(date), clock(time)的逻辑，先看两个没用的函数。

datetime — Date and Time Value Manipulation — PyMOTW 3

1. datetime.date()

   class date(builtins.object)  就是符号%x返回的内容
    |  date(year, month, day) --> date object
   In [135]: datetime.date.today().year
   Out[135]: 2019
   In [136]: datetime.date.today().month
   Out[136]: 5
   In [137]: datetime.date.today().day
   Out[137]: 9
   

2. datetime.time()

   class time(builtins.object) 符号%X返回的内容
    |  time([hour[, minute[, second[, microsecond[, tzinfo]]]]]) --> a time object
     #5个参数,由大到小排列
   In [104]:  t = datetime.time(6, 15, 30, 999999, dateutil.tz.tzutc())
   In [105]: t.strftime("%f:%S:%M:%H %Z")
   Out[105]: '999999:30:15:06 UTC'
   In [106]: t.min
   Out[106]: datetime.time(0, 0)
   In [107]: t.max
   Out[107]: datetime.time(23, 59, 59, 999999)
   In 108]: t.resolution
   Out[108]: datetime.timedelta(microseconds=1) #精确度
   

3. datetime.datetime

   #前面两个datetime.time and datetime.date没啥用.
   #这里的关键是第十个时间变量tzinfo
   class datetime(date)
    |  datetime(year, month, day[, hour[, minute[, second[, microsecond[,tzinfo]]]]])
   Help on built-in function weekday:
   
   weekday(...) method of datetime.datetime instance
       Return the day of the week represented by the date.
       Monday == 0 ... Sunday == 6
   In [200]: dt = datetime.datetime.now().replace(tzinfo=dateutil.tz.gettz("Asia/Shanghai"))
   In [201]: dt
   Out[201]: datetime.datetime(2019, 5, 9, 17, 47, 10, 421561, tzinfo=tzfile('/usr/share/zoneinfo/Asia/Shanghai'))
    In [208]: datetime.datetime.utcnow().timetuple()
   Out[208]: time.struct_time(tm_year=2019, tm_mon=5, tm_mday=9, tm_hour=9, tm_min=49, tm_sec=24, tm_wday=3, tm_yday=129, tm_isdst=-1)
   

4. datetime.timedelta and Arithmetic Opertions

   class datetime.timedelta(days=0, seconds=0, microseconds=0, milliseconds=0, minutes=0, hours=0, weeks=0)
   In [219]: datetime.datetime.now() + datetime.timedelta(days=-1)
   Out[219]: datetime.datetime(2019, 5, 8, 17, 57, 40, 910880)
   In [220]: !date -d "1 days ago"
   Wed May  8 17:57:52 CST 2019
    #转换为seconds的另外一种写法
   In [25]: str(datetime.timedelta(seconds=100))
   Out[25]: '0:01:40'
   In [29]: time.strftime("%H:%M:%S", time.gmtime(3000))
   Out[29]: '00:50:00'
   

1.Calendar

$ ncal -1
$ ncal -M #Monday as the first day
$ ncal -w #weeknumber
$ncal -y -m;
$ncal -d yyyy-mm
$ncal yyyy-mm-dd#highlight the current date
$ ncal -A3 -B4
#就只有这么多操作

2.Clock(Time)

• hwclock

  In [31]: !sudo hwclock
  2019-05-15 21:25:29.514803+08:00
  ---------------------------------------------------
  NAME
         hwclock - time clocks utility
  FILES
         /etc/adjtime
                The configuration and state file for hwclock.
         /etc/localtime
                The system timezone file
         /usr/share/zoneinfo/
                The system timezone database directory.
         Device files hwclock may try for Hardware Clock access:
         /dev/rtc0
         /dev/rtc
         /dev/misc/rtc
         /dev/efirtc
         /dev/misc/efirtc
  

• time (processing profile)

      $ time (tree  /usr/share/zoneinfo | grep -i "prc")
      │   ├── Chongqing -> ../PRC
      │   ├── Chungking -> ../PRC
      │   ├── Harbin -> ../PRC
      │   ├── Shanghai -> ../PRC
      │   │   ├── Chongqing -> ../../PRC
      │   │   ├── Chungking -> ../../PRC
      │   │   ├── Harbin -> ../../PRC
      │   │   ├── Shanghai -> ../../PRC
      │   ├── PRC -> ../PRC
      ├── PRC
      │   │   ├── Chongqing -> ../PRC
      │   │   ├── Chungking -> ../PRC
      │   │   ├── Harbin -> ../PRC
      │   │   ├── Shanghai -> ../PRC
      │   ├── PRC
  
      real    0m0.017s
      user    0m0.015s
      sys     0m0.004s
  
  3.Datetime
  

3.Datetime

• timedatectl

  #systemd的service
  $ timedatectl
                 Local time: Thu 2019-05-09 21:30:27 CST
             Universal time: Thu 2019-05-09 13:30:27 UTC
                   RTC time: Thu 2019-05-09 13:30:27
                  Time zone: Asia/Shanghai (CST, +0800)
  System clock synchronized: yes
                NTP service: active
  
   - Check the current system clock time:
     timedatectl
   - Set the local time of the system clock directly:
     timedatectl set-time {{"yyyy-MM-dd hh:mm:ss"}}
  
   - List available timezones:
     timedatectl list-timezones
  
   - Set the system timezone:
     timedatectl set-timezone {{timezone}}
  
   - Enable Network Time Protocol (NTP) synchronization:
     timedatectl set-ntp on
  

• date (最趁手的一个工具)

  # 日常应用date作为思考工具.
  In [9]: time.time()
  Out[9]: 1557406444.1336956
  In [10]: !date +%s
  1557406449
  $ date -d @$(date +%s)　#date -d @1557406449
  Thu May  9 21:11:15 CST 2019
  
  #基本的操作
  $ date -u +"%Y-%m-%dT%H:%M:%SZ"
  2019-05-09T12:55:31Z
  
  #Future date and time
  $ date -d " two weeks"
  date: invalid date ‘ two weeks’
  $ date -d "2 weeks"
  Thu May 23 21:20:17 CST 2019
  $ date -d "next fri" #只有两个变量能够以文字表述 Month and Weekday
  Fri May 10 00:00:00 CST 2019
  
  #the elpased date and time
  $ date -d "last thursday"
  Thu May  2 00:00:00 CST 2019
  $ date -d "2 days ago"
  Tue May  7 21:22:28 CST 2019
  $ date -d "last month"
  Tue Apr  9 21:22:39 CST 2019
  
  #贸易战倒计时
  $ TZ="America/New_York" date
  Thu May  9 20:04:30 EDT 2019