help-time

Posted 2021-01-05 yanmingjiang

NAME

　　time - This module provides various functions to manipulate time values.

DESCRIPTION
　　There are two standard representations of time. One is the number of seconds since the Epoch, in UTC (a.k.a. GMT). It may be an integer or a floating point number (to represent fractions of seconds).
　　The Epoch is system-defined; on Unix, it is generally January 1st, 1970.
　　The actual value can be retrieved by calling gmtime(0).

　　The other representation is a tuple of 9 integers giving local time.
　　The tuple items are:
　　　　year (including century, e.g. 1998)
　　　　month (1-12)
　　　　day (1-31)
　　　　hours (0-23)
　　　　minutes (0-59)
　　　　seconds (0-59)
　　　　weekday (0-6, Monday is 0)
　　　　Julian day (day in the year, 1-366)
　　　　DST (Daylight Savings Time) flag (-1, 0 or 1)
　　If the DST flag is 0, the time is given in the regular time zone;
　　if it is 1, the time is given in the DST time zone;
　　if it is -1, mktime() should guess based on the date and time.

　　Variables:

　　timezone -- difference in seconds between UTC and local standard time
　　altzone -- difference in seconds between UTC and local DST time
　　daylight -- whether local time should reflect DST
　　tzname -- tuple of (standard time zone name, DST time zone name)

　　Functions:

　　time() -- return current time in seconds since the Epoch as a float
　　clock() -- return CPU time since process start as a float
　　sleep() -- delay for a number of seconds given as a float
　　gmtime() -- convert seconds since Epoch to UTC tuple
　　localtime() -- convert seconds since Epoch to local time tuple
　　asctime() -- convert time tuple to string
　　ctime() -- convert time in seconds to string
　　mktime() -- convert local time tuple to seconds since Epoch
　　strftime() -- convert time tuple to string according to format specification
　　strptime() -- parse string to time tuple according to format specification
　　tzset() -- change the local timezone

CLASSES
　　builtins.tuple(builtins.object)
　　　　struct_time

　　class struct_time(builtins.tuple)
　　| 　The time value as returned by gmtime(), localtime(), and strptime(), and
　　|     accepted by asctime(), mktime() and strftime(). May be considered as a
　　|     sequence of 9 integers.
　　|
　　|     Note that several fields‘ values are not the same as those defined by
　　|     the C language standard for struct tm. For example, the value of the
　　|     field tm_year is the actual year, not year - 1900. See individual
　　|     fields‘ descriptions for details.
　　|
　　|     Method resolution order:
　　|　　  struct_time
　　| 　　 builtins.tuple
　　| 　　 builtins.object
　　|
　　|     Methods defined here:
　　|
　　| 　　 __new__(*args, **kwargs) from builtins.type
　　| 　　　　 Create and return a new object. See help(type) for accurate signature.
　　|
　　| 　　 __reduce__(...)
　　| 　　　　 helper for pickle
　　|
　　| 　　 __repr__(self, /)
　　| 　　　　 Return repr(self).
　　|
　　| ----------------------------------------------------------------------
　　| 　Data descriptors defined here:
　　|
　　|     tm_gmtoff
　　| 　　 offset from UTC in seconds
　　|
　　|     tm_hour
　　| 　　 hours, range [0, 23]
　　|
　　|     tm_isdst
　　| 　　 1 if summer time is in effect, 0 if not, and -1 if unknown
　　|
　　|     tm_mday
　　| 　　 day of month, range [1, 31]
　　|
　　|     tm_min
　　| 　　 minutes, range [0, 59]
　　|
　　|     tm_mon
　　| 　　 month of year, range [1, 12]
　　|
　　|     tm_sec
　　| 　　 seconds, range [0, 61])
　　|
　　|     tm_wday
　　| 　　 day of week, range [0, 6], Monday is 0
　　|
　　|     tm_yday
　　| 　　 day of year, range [1, 366]
　　|
　　|     tm_year
　　| 　　 year, for example, 1993
　　|
　　|     tm_zone
　　| 　　 abbreviation of timezone name
　　|
　　| ----------------------------------------------------------------------
　　|     Data and other attributes defined here:
　　|
　　| 　　 n_fields = 11
　　|
　　| 　　 n_sequence_fields = 9
　　|
　　| 　　 n_unnamed_fields = 0
　　|
　　| ----------------------------------------------------------------------
　　|     Methods inherited from builtins.tuple:
　　|
　　| 　　 __add__(self, value, /)
　　| 　　 　　 Return self+value.
　　|
　　|  　　__contains__(self, key, /)
　　| 　　 　　 Return key in self.
　　|
　　| 　　 __eq__(self, value, /)
　　| 　　　　 Return self==value.
　　|
　　| 　　 __ge__(self, value, /)
　　| 　　　　 Return self>=value.
　　|
　　| 　　 __getattribute__(self, name, /)
　　| 　　　　 Return getattr(self, name).
　　|
　　| 　　 __getitem__(self, key, /)
　　| 　　　　 Return self[key].
　　|
　　|　　 __getnewargs__(...)
　　|
　　| 　　__gt__(self, value, /)
　　| 　　　　Return self>value.
　　|
　　| 　　 __hash__(self, /)
　　| 　　　　 Return hash(self).
　　|
　　| 　　 __iter__(self, /)
　　| 　　　　 Implement iter(self).
　　|
　　| 　　 __le__(self, value, /)
　　| 　　　　 Return self<=value.
　　|
　　| 　　 __len__(self, /)
　　| 　　　　 Return len(self).
　　|
　　| 　　 __lt__(self, value, /)
　　| 　　　　 Return self<value.
　　|
　　| 　　 __mul__(self, value, /)
　　| 　　 　　 Return self*value.n
　　|
　　| 　　 __ne__(self, value, /)
　　| 　　　　 Return self!=value.
　　|
　　| 　　 __rmul__(self, value, /)
　　| 　　　　 Return self*value.
　　|
　　| 　　 count(...)
　　| 　　　　 T.count(value) -> integer -- return number of occurrences of value
　　|
　　| 　　 index(...)
　　| 　　　　 T.index(value, [start, [stop]]) -> integer -- return first index of value.
　　| 　　　　 Raises ValueError if the value is not present.

FUNCTIONS
　　asctime(...)
　　　　asctime([tuple]) -> string

　　　　Convert a time tuple to a string, e.g. ‘Sat Jun 06 16:26:11 1998‘.
　　　　When the time tuple is not present, current time as returned by localtime() is used.

　　clock(...)
　　　　clock() -> floating point number

　　　　Return the CPU time or real time since the start of the process or since the first call to clock(). This has as much precision as the system records.

　　ctime(...)
　　　　ctime(seconds) -> string

　　　　Convert a time in seconds since the Epoch to a string in local time.
　　　　This is equivalent to asctime(localtime(seconds)). When the time tuple is not present, current time as returned by localtime() is used.

　　get_clock_info(...)
　　　　get_clock_info(name: str) -> dict

　　　　Get information of the specified clock.

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

　　　　Convert seconds since the Epoch to a time tuple expressing UTC (a.k.a. GMT). When ‘seconds‘ is not passed in, convert the current time instead.

　　　　If the platform supports the tm_gmtoff and tm_zone, they are available as attributes only.

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

　　　　Convert seconds since the Epoch to a time tuple expressing local time.
　　　　When ‘seconds‘ is not passed in, convert the current time instead.

　　mktime(...)
　　　　mktime(tuple) -> floating point number

　　　　Convert a time tuple in local time to seconds since the Epoch.
　　　　Note that mktime(gmtime(0)) will not generally return zero for most time zones; instead the returned value will either be equal to that of the timezone or altzone attributes on the time module.

　　monotonic(...)
　　　　monotonic() -> float

　　　　Monotonic clock, cannot go backward.

　　perf_counter(...)
　　　　perf_counter() -> float

　　　　Performance counter for benchmarking.

　　process_time(...)
　　　　process_time() -> float

　　　　Process time for profiling: sum of the kernel and user-space CPU time.

　　sleep(...)
　　　　sleep(seconds)

　　　　Delay execution for a given number of seconds. The argument may be a floating point number for subsecond precision.

　　strftime(...)
　　　　strftime(format[, tuple]) -> string

　　　　Convert a time tuple to a string according to a format specification.
　　　　See the library reference manual for formatting codes. When the time tuple is not present, current time as returned by localtime() is used. Commonly used format codes:

　　　　　　%Y Year with century as a decimal number.
　　　　　　%m Month as a decimal number [01,12].
　　　　　　%d Day of the month as a decimal number [01,31].
　　　　　　%H Hour (24-hour clock) as a decimal number [00,23].
　　　　　　%M Minute as a decimal number [00,59].
　　　　　　%S Second as a decimal number [00,61].
　　　　　　%z Time zone offset from UTC.
　　　　　　%a Locale‘s abbreviated weekday name.
　　　　　　%A Locale‘s full weekday name.
　　　　　　%b Locale‘s abbreviated month name.
　　　　　　%B Locale‘s full month name.
　　　　　　%c Locale‘s appropriate date and time representation.
　　　　　　%I Hour (12-hour clock) as a decimal number [01,12].
　　　　　　%p Locale‘s equivalent of either AM or PM.

　　　　Other codes may be available on your platform. See documentation for the C library strftime function.

　　strptime(...)
　　　　strptime(string, format) -> struct_time

　　　　Parse a string to a time tuple according to a format specification.
　　　　See the library reference manual for formatting codes (same as strftime()).

　　　　Commonly used format codes:

　　　　　　%Y Year with century as a decimal number.
　　　　　　%m Month as a decimal number [01,12].
　　　　　　%d Day of the month as a decimal number [01,31].
　　　　　　%H Hour (24-hour clock) as a decimal number [00,23].
　　　　　　%M Minute as a decimal number [00,59].
　　　　　　%S Second as a decimal number [00,61].
　　　　　　%z Time zone offset from UTC.
　　　　　　%a Locale‘s abbreviated weekday name.
　　　　　　%A Locale‘s full weekday name.
　　　　　　%b Locale‘s abbreviated month name.
　　　　　　%B Locale‘s full month name.
　　　　　　%c Locale‘s appropriate date and time representation.
　　　　　　%I Hour (12-hour clock) as a decimal number [01,12].
　　　　　　%p Locale‘s equivalent of either AM or PM.

　　Other codes may be available on your platform. See documentation for the C library strftime function.

　　time(...)
　　　　time() -> floating point number

　　　　Return the current time in seconds since the Epoch.
　　　　Fractions of a second may be present if the system clock provides them.

DATA
　　altzone = -32400
　　daylight = 0
　　timezone = -28800
　　tzname = (‘xd6xd0xb9ú±ê×xbcxca±xbcxe4‘, ‘xd6xd0xb9úxcfxc4xc1xeexca±‘)

FILE
　　(built-in)