python之time模块
发布时间：2021-05-21 05:57:02 所属栏目：大数据 来源： https://www.jb51.cc
导读：? 在我们学习的过程中，肯定会用到各种各样的模块。所以今天我们从 time模块 开始学习 首先我们在使用某个模块的时候，肯定要先 导入 这个模块 import time ?而当我们想看看这个模块是干什么的，我们可以使用 help函数 来看 print (help(time)) # 打印帮助信
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? 在我们学习的过程中，肯定会用到各种各样的模块。所以今天我们从time模块开始学习 首先我们在使用某个模块的时候，肯定要先导入这个模块 import time
?而当我们想看看这个模块是干什么的，我们可以使用help函数来看 print(help(time)) # 打印帮助信息
1 "E:Program Files (x86)python_3.8python.exe" D:/Application/pycharm_works/_1/test/python模块之time模块.py 2 Help on built-in module time: 3 4 NAME 5 time - This module provides varIoUs functions to manipulate time values. 6 7 DESCRIPTION 8 There are two standard representations of time. One is the number 9 of seconds since the Epoch, UTC (a.k.a. GMT). It may be an integer 10 or a floating point number (to represent fractions of seconds). 11 The Epoch is system-defined; on Unix,it is generally January 1st,1970. 12 The actual value can be retrieved by calling gmtime(0). 13 14 The other representation is a tuple of 9 integers giving local time. 15 The tuple items are: 16 year (including century,e.g. 1998) 17 month (1-12 18 day (1-31 19 hours (0-23 20 minutes (0-59 21 seconds (0-59 22 weekday (0-6,Monday 0) 23 Julian day (day in the year,1-366 24 DST (Daylight Savings Time) flag (-1,0 or 1 25 If the DST flag is 0,the time is given the regular time zone; 26 if it is 1,1)"> the DST time zone; 27 is -1,mktime() should guess based on the date and time. 28 29 CLASSES 30 builtins.tuple(builtins.object) 31 struct_time 32 33 class struct_time(builtins.tuple) 34 | struct_time(iterable=(),/ 35 | 36 | The time value as returned by gmtime(),localtime(),1)">and strptime(),1)">and 37 | accepted by asctime(),mktime() strftime(). May be considered as a 38 | sequence of 9 integers. 39 | 40 | Note that several fields' values are not the same as those defined by 41 | the C language standard for struct tm. For example,the value of the 42 | field tm_year is the actual year,1)">not year - 1900. See individual 43 | fields descriptions for details. 44 | 45 | Method resolution order: 46 | struct_time 47 | builtins.tuple 48 | builtins.object 49 | 50 | Methods defined here: 51 | 52 | __reduce__(...) 53 | Helper pickle. 54 | 55 | __repr__(self,1)"> 56 | Return repr(self). 57 | 58 | ---------------------------------------------------------------------- 59 | Static methods defined here: 60 | 61 | __new__(*args,**kwargs) from builtins.type 62 | Create and return a new object. See help(type) accurate signature. 63 | 64 | ---------------------------------------------------------------------- 65 | Data descriptors defined here: 66 | 67 | tm_gmtoff 68 | offset from UTC seconds 69 | 70 | tm_hour 71 | hours,range [0,23] 72 | 73 | tm_isdst 74 | 1 if summer time is in effect,1)">if not,1)">and -1 if unknown 75 | 76 | tm_mday 77 | day of month,range [1,31 78 | 79 | tm_min 80 | minutes,59 81 | 82 | tm_mon 83 | month of year,12 84 | 85 | tm_sec 86 | seconds,61]) 87 | 88 | tm_wday 89 | day of week,6],1)"> 0 90 | 91 | tm_yday 92 | day of year,366 93 | 94 | tm_year 95 | year,1)">for example,1993 96 | 97 | tm_zone 98 | abbreviation of timezone name 99 | 100 | ---------------------------------------------------------------------- 101 | Data other attributes defined here: 102 | 103 | n_fields = 11 104 | 105 | n_sequence_fields = 9 106 | 107 | n_unnamed_fields =108 | 109 | ---------------------------------------------------------------------- 110 | Methods inherited builtins.tuple: 111 | 112 | __add__(self,value,1)">113 | Return self+value. 114 | 115 | __contains__(self,key,1)">116 | Return key self. 117 | 118 | __eq__(self,1)">119 | Return self==120 | 121 | __ge__(self,1)">122 | Return self>=123 | 124 | __getattribute__(self,name,1)">125 | Return getattr(self,name). 126 | 127 | __getitem__(self,1)">128 | Return self[key]. 129 | 130 | __getnewargs__(self,1)">131 | 132 | __gt__(self,1)">133 | Return self>134 | 135 | __hash__(self,1)">136 | Return hash(self). 137 | 138 | __iter__(self,1)">139 | Implement iter(self). 140 | 141 | __le__(self,1)">142 | Return self<=143 | 144 | __len__(self,1)">145 | Return len(self). 146 | 147 | __lt__(self,1)">148 | Return self<149 | 150 | __mul__(self,1)">151 | Return self*152 | 153 | __ne__(self,1)">154 | Return self!=155 | 156 | __rmul__(self,1)">157 | Return value*self. 158 | 159 | count(self,1)">160 | Return number of occurrences of value. 161 | 162 | index(self,start=0,stop=9223372036854775807,1)">163 | Return first index of value. 164 | 165 | Raises ValueError if the value not present. 166 167 FUNCTIONS 168 asctime(...) 169 asctime([tuple]) -> string 170 171 Convert a time tuple to a string,e.g. Sat Jun 06 16:26:11 1998'172 When the time tuple present,current time as returned by localtime() 173 used. 174 175 ctime(...) 176 ctime(seconds) ->177 178 Convert a time in seconds since the Epoch to a string local time. 179 This is equivalent to asctime(localtime(seconds)). When the time tuple is 180 not present,current time as returned by localtime() 181 182 get_clock_info(...) 183 get_clock_info(name: str) -> dict 184 185 Get information of the specified clock. 186 187 gmtime(...) 188 gmtime([seconds]) -> (tm_year,tm_mon,tm_mday,tm_hour,tm_min,189 tm_sec,tm_wday,tm_yday,tm_isdst) 190 191 Convert seconds since the Epoch to a time tuple expressing UTC (a.k.a. 192 GMT). When seconds' not passed ,convert the current time instead. 193 194 If the platform supports the tm_gmtoff tm_zone,they are available as 195 attributes only. 196 197 localtime(...) 198 localtime([seconds]) ->199 tm_sec,1)">200 201 Convert seconds since the Epoch to a time tuple expressing local time. 202 When 203 204 mktime(...) 205 mktime(tuple) -> floating point number 206 207 Convert a time tuple local time to seconds since the Epoch. 208 Note that mktime(gmtime(0)) will not generally return zero most 209 time zones; instead the returned value will either be equal to that 210 of the timezone altzone attributes on the time module. 211 212 monotonic(...) 213 monotonic() -> float 214 215 Monotonic clock,cannot go backward. 216 217 monotonic_ns(...) 218 monotonic_ns() -> int 219 220 221 222 perf_counter(...) 223 perf_counter() ->224 225 Performance counter benchmarking. 226 227 perf_counter_ns(...) 228 perf_counter_ns() ->229 230 Performance counter benchmarking as nanoseconds. 231 232 process_time(...) 233 process_time() ->234 235 Process time for profiling: sum of the kernel and user-space cpu time. 236 237 process_time_ns(...) 238 process_time() ->239 240 Process time profiling as nanoseconds: 241 sum of the kernel 242 243 sleep(...) 244 sleep(seconds) 245 246 Delay execution a given number of seconds. The argument may be 247 a floating point number subsecond precision. 248 249 strftime(...) 250 strftime(format[,tuple]) ->251 252 Convert a time tuple to a string according to a format specification. 253 See the library reference manual formatting codes. When the time tuple 254 255 256 Commonly used format codes: 257 258 %Y Year with century as a decimal number. 259 %m Month as a decimal number [01,1)">]. 260 %d Day of the month as a decimal number [01,1)">261 %H Hour (24-hour clock) as a decimal number [00,1)">262 %M Minute as a decimal number [00,1)">263 %S Second as a decimal number [00,1)">264 %z Time zone offset UTC. 265 %a Locales abbreviated weekday name. 266 %A Locales full weekday name. 267 %b Locales abbreviated month name. 268 %B Locales full month name. 269 %c Locales appropriate date and time representation. 270 %I Hour (12-hour clock) as a decimal number [01,1)">271 %p Locales equivalent of either AM or PM. 272 273 Other codes may be available on your platform. See documentation for 274 the C library strftime function. 275 276 strptime(...) 277 strptime(string,format) -> struct_time 278 279 Parse a string to a time tuple according to a format specification. 280 See the library reference manual formatting codes (same as 281 strftime()). 282 283 284 285 %286 %m Month as a decimal number [01,1)">287 %d Day of the month as a decimal number [01,1)">288 %H Hour (24-hour clock) as a decimal number [00,1)">289 %M Minute as a decimal number [00,1)">290 %S Second as a decimal number [00,1)">291 %z Time zone offset 292 %a Locale293 %A Locale294 %b Locale295 %B Locale296 %c Locale297 %I Hour (12-hour clock) as a decimal number [01,1)">298 %p Locale299 300 Other codes may be available on your platform. See documentation 301 302 303 thread_time(...) 304 thread_time() ->305 306 Thread time 307 308 thread_time_ns(...) 309 thread_time() ->310 311 Thread time 312 sum of the kernel 313 314 time(...) 315 time() ->316 317 Return the current time seconds since the Epoch. 318 Fractions of a second may be present the system clock provides them. 319 320 time_ns(...) 321 time_ns() ->322 323 Return the current time nanoseconds since the Epoch. 324 325 DATA 326 altzone = -32400 327 daylight =328 timezone = -28800 329 tzname = (中国标准时间',中国夏令时330 331 FILE 332 (built-333 334 335 None 336 337 Process finished with exit code 0View Code ?那么接下来我们挨个来看看 1.?time.time()为当前时间戳，从1900年开始到当前时间的秒数 print(help(time.time)) 打印帮助信息 print(time.time()) 1610720236.653394 # 打印当前时间戳
1 Help on built-in function time 2 3 time(...) 4 time() -> 5 6 Return the current time 7 Fractions of a second may be present 8 9 10 1610727247.1696546View Code 2.?time.sleep(secs)?让程序暂停secs秒 1 print(help(time.sleep)) 打印帮助信息 2 time.sleep(3) 暂停3秒
1 Help on built-in function sleep 2 3 sleep(...) 4 sleep(seconds) 5 6 Delay execution 7 a floating point number 8 9 NoneView Code ? 3.time.gmtime()?结构化时间，不过要注意的一点是这个时间是世界标准时间（格林尼治时间） 1 print(help(time.gmtime)) 打印帮助信息 2 print(time.gmtime()) 结构化时间 time.struct_time(tm_year=2021,tm_mon=1,tm_mday=15,tm_hour=14,tm_min=22,tm_sec=30,tm_wday=4,tm_yday=15,tm_isdst=0)
in function gmtime gmtime(...) 4 gmtime([seconds]) -> 5 tm_sec,1)"> 6 7 Convert seconds since the Epoch to a time tuple expressing UTC (a.k.a. 8 GMT). When 9 10 If the platform supports the tm_gmtoff 11 attributes only. 12 13 14 time.struct_time(tm_year=2021,tm_hour=16,tm_min=16,tm_sec=39,tm_isdst=0)View Code 不过这时肯定有人该问了，那我们的当地时间怎么表示呢，所以我们来介绍下一个 4.time.localtime()结构化时间，当前时间 1 print(help(time.localtime)) print(time.localtime()) 当前结构化时间
in function localtime localtime(...) 4 localtime([seconds]) -> tm_sec,1)"> Convert seconds since the Epoch to a time tuple expressing local time. 8 When 9 10 11 time.struct_time(tm_year=2021,tm_mday=16,tm_hour=0,tm_min=17,tm_sec=49,tm_wday=5,tm_yday=16,tm_isdst=0)View Code ? 总说结构化时间，那结构化时间是什么呢，我们来看看里面的参数 1 我们来拿上面这个例子来解释： 2 3 tm_year=2021 当前所在年 4 tm_mon=1 当前所在月 5 tm_mday=15 当前所在天 6 tm_hour=23 当前所在时 7 tm_min=18 当前所在分 8 tm_sec=57 当前所在秒 9 tm_wday=4 当前周的第几天 10 tm_yday=15 当前年的第几天 但是有时候我们需要的并不是结构化时间，而是类似于 2021-01-15 23:28:26 这样的格式化时间，那我们应该怎么做呢？ 6.?time.strftime()?将结构话时间化为格式化时间 1 print(help(time.strftime)) 打印帮助信息 2 struct_time=time.localtime() 3 print(time.strftime(%Y-%m-%d %H:%M:%S",struct_time)) 格式化时间
in function strftime strftime(...) 4 strftime(format[,1)"> 6 Convert a time tuple to a string according to a format specification. 7 See the library reference manual 8 Commonly used format codes: 11 12 %13 %m Month as a decimal number [01,1)">14 %d Day of the month as a decimal number [01,1)">15 %H Hour (24-hour clock) as a decimal number [00,1)">16 %M Minute as a decimal number [00,1)">17 %S Second as a decimal number [00,1)">18 %z Time zone offset 19 %a Locale20 %A Locale21 %b Locale22 %B Locale23 %c Locale24 %I Hour (12-hour clock) as a decimal number [01,1)">25 %p Locale26 27 Other codes may be available on your platform. See documentation 28 the C library strftime function. 29 30 31 2021-01-16 00:18:38View Code 同样这里为什么要写成?"%Y-%m-%d %H:%M:%S"?呢，就是为了控制时间的格式。 那这些都表示什么呢，我们来看看 1 %Y Year with century as a decimal number. 2 %m Month as a decimal number [01,12]. 3 %d Day of the month as a decimal number [01,31]. 4 %H Hour (24-hour clock) as a decimal number [00,23]. 5 %M Minute as a decimal number [00,59]. 6 %S Second as a decimal number [00,61]. 7 %z Time zone offset from UTC. 8 %a Locale's abbreviated weekday name. 9 %A Locale's full weekday name. 10 %b Locale's abbreviated month name. 11 %B Locale's full month name. 12 %c Locale's appropriate date and time representation. 13 %I Hour (12-hour clock) as a decimal number [01,12]. 14 %p Locale's equivalent of either AM or PM. 不过似乎也可以单独使用? ?time.strftime（），我们来看看结果，但是我们必须要把格式加上，如下所示： ")) 格式化时间 # 2021-01-15 23:36:49 那么，有时候我们也需要把格式化时间转化为结构化时间来使用，这时我们仅仅需要看看接下来的知识就能掌握 7.?time.strptime()?将格式化时间(字符串)转化为结构化时间 print(help(time.strftime))
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当然以上只是一个举例，具体我们可以采用如下方式： a=time.strptime(2021-01-15 22:26:28"print(a.tm_yday) 15 print(a.tm_wday) 4 最后，我们快接近了尾声，最后我们再介绍两个就结束了 8.?time.ctime()?将所给时间戳转变为一个格式化时间 1 print(help(time.ctime)) 将时间戳转变为一个格式化时间 2 print(time.ctime()) 如果不带参数则默认为当前时间戳 3 print(time.ctime(12412415))
in function ctime ctime(...) 4 ctime(seconds) -> 6 Convert a time 7 This 11 Sat Jan 16 00:21:56 2021 12 Sun May 24 23:53:35 1970View Code 9.time.mktime()??将所给结构化时间转化为时间戳 1 print(time.mktime(time.localtime())) 将结构化时间转化为时间戳
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不过值得一提的是，这种方式得到的时间戳精度要比time.time()低的多 最后，在提供一种其他求当前时间的方法 import datetime print(datetime.datetime.now()) 2021-01-15 23:55:48.985808 本次time模块便到此结束，其他模块下次讲解 ? （编辑：北几岛） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |
