The 3-in-3 representation format of the time, and the conversion between them:
In Python, there are usually three ways to represent time: timestamp, tuple (struct_time), formatted time string:
(1) Timestamp: Generally speaking, a timestamp represents an offset calculated in seconds from 00:00:00 on January 1, 1970. We run "type(time.time())" and it returns a float.
(2) Formatted time string (Format String): '2018-04-18'
(3) Tuple (struct_time): There are 9 elements in the struct_time tuple: (year, month, day, hour, minute, second, week of the year, day of the year, etc.)
Uses: Timestamps are times that computers can recognize; time strings are times that people can understand; tuples are used to manipulate time
Convert:
1. Timestamp --> Formatting --> String
_now = time.time() # timestamp
struct_time = time.localtime(_now) # Convert timestamp to formatted time
time.strftime("%Y-%m-%d %X", struct_time) # 2018-04-21 22:44:53
1. String --> Formatting --> Timestamp
str_time = '2018-04-18 08:00:00' struct_time2 = time.strptime(str_time,'%Y-%m-%d %H:%M:%S') # string to format timestamp = time.mktime(struct_time2) # format to timestamp# =======The above is the time module, and the bottom is the datetime module ===========================
import datetime
# 1. Timestamp-->Formatting-->Character
timestamp1 = 1509636585.0 # 2018-04-21 23:47:02.886948 # Convert timestamp to formatted (datetime type) time struct_time = datetime.datetime.fromtimestamp(1509636585.0) # 类型:<class 'datetime.datetime'> # Format to string type str_time = datetime.datetime.strftime(struct_time,'%Y-%m-%d %H:%M:%S') # 2017-11-02 23:29:45
# 2. Character-->Formatting--> Timestamp
str_time1 = '2017-11-02 23:29:45' # string --> format struct_time = datetime.datetime.strptime(str_time1,'%Y-%m-%d %H:%M:%S') # Formatting-->Timestamp time_stamp = time.mktime(struct_time.timetuple()) # 1509636585.0
Calculation between time
# interval between times # 1. Time delay, advance calculation now =datetime.datetime.now() # this time tomorrow tomorrow_now = now + datetime.timedelta(days=1) # this time yesterday yes_now = now + datetime.timedelta(days=-1) # 2. Difference between two times days = (tomorrow_now - yes_now).days # 2