day27 module

collectons module

from collections import OrderedDict
# d = OrderedDict()
# d['a'] = 1
# d['z'] = 2
# d['b'] = 3
# print(d) #ordered #d 
['z'] = 0 
#change #print(d)

　default dictionary

　　Example: There are the following value sets [11, 22, 33, 44, 55, 66, 77, 88, 99, 90], save the value greater than 66 to the value of the first key, and save the value less than 66 to of the second key.

# dec = {}
# dic.setdefault('k',[])
# print (Dec)


# dec = {}
# l = [11,22,33,44,55,66,77,88,99,90]
# for i in l :
#     if i > 66:
#         if dic.get('k1'):
#             dic['k1'].append(i)
#         else:
#             dic['k1']=[i]
#     elif i < 66 :
#         if dic.get('k2'):
#             dic['k2'].append(i)
#         else:
# dic ['to'] = [i]
# print (Dec)


# from collections import defaultdict
# d = defaultdict(list)
# l = [11,22,33,44,55,66,77,88,99,90]
# for i in l:
#     if i > 66:
#         d['k1'].append(i)
#     elif i < 66:
#         d['k2'].append(i)
# print(d)
# from collections import defaultdict
# d = defaultdict(lambda :5)
# print(d[1])
# print(d)
# from collections import Counter
# c = Counter('abcdeabcdabcd')
# print(c)

The default dictionary can either let its default value be a dictionary, list, set, or let its default value be a number, a string.

The biggest advantage of default dictionaries is that you will never get an error when you use a fetchable value.

The default dictionary is to set the default value for the value in the dictionary.　

counter module

# from collections import Counter
# c = Counter('abcdeabcdabcaba')
# print(c)

collections module

# class Configparser:
#     def __init__(self,section,option):
#         self.section = section
#         self.option = option
#     def write(self,f):
#         f.write(self.section)
# f = open('test','w')
# config = Configparser('a','b')
# config.write(f)


# import configparser
# configparser.ConfigParser.write()

item module

import time

time.time() Microsoft's time synchronization server

time

Calculate the time to execute the code time.time()

Let the program stop here for a while and sleep

Format of record time:

　　for people to see

　　for the machine

　　for calculation

time.sleep(set)

Delay the run for the specified time, in seconds

time.time()

Get current timestamp

# import time
# timestamp time
# print(time.time()) # Timestamp time # Accurate calculation of time difference
#Format time
# print(time.strftime('%Y-%m-%d %H:%M:%S'))# String formatting time # Record it for people to see
# print(time.strftime('%y-%m-%d'))# string format time
# print(time.strftime('%x %X'))# string format time
# print(time.strftime('%c'))# string format time
# structured time
# print(time.localtime())# Local structured time # Middleware for converting timestamp time to formatted time
                                                # Simple calculation of the corresponding term
# print(time.gmtime()) # UK structured time

Structured time is an intermediate value between formatted time and timestamp

example

2015-8-8 Timestamp time

# p = time.strptime('2015-8-8','%Y-%m-%d')
# print(p)
# print(time.mktime(p))
# print(time.time()-time.mktime(p))

# print(time.time())
#
# ret = time.localtime (1500000000)
# print (ret)
# print(time.strftime('%Y-%m-%d %H:%M:%S',ret))

# ret = time.localtime (2000000000)
# print (ret)
# print(time.strftime('%Y-%m-%d %H:%M:%S',ret))

# ret = time.localtime (3000000000)
# print (ret)
# print(time.strftime('%Y-%m-%d %H:%M:%S',ret))  #2033   2065    32

# ret = time.localtime (0)
# print (ret)
# print(time.strftime('%Y-%m-%d %H:%M:%S',ret))  #1970 1 1 8
#
# ret = time.gmtime (0)
# print (ret)
# print(time.strftime('%Y-%m-%d %H:%M:%S',ret))  #1970 1 1 0


# print(time.strftime('%c'))
# print(time.ctime(1500000000))

# ret = time.localtime (2000000000)
# print (ret)
# print(time.asctime())
# print (time.asctime (ret))

sys module and os module

# sys.argv command line parameter list, the first element is the path of the program itself
# sys.exit(n) Exit the program, exit(0) when exiting normally, exit sys.exit(1) in error
# sys.version Get the version information of the Python interpreter
# sys.path returns the search path of the module, using the value of the PYTHONPATH environment variable during initialization
# sys.platform returns the operating system platform name

# import sys
# print('*'*6)
# sys.exit() #Exit the program, exit(0) when exiting normally, exit sys.exit(1) with error
# print('-'*6)

# import sys
# print(sys.version)

# import sys
# print(sys.platform)

# import sys    # *****
# print(sys.path)

RAM:

　　while the program is running

　　Start the interpreter to load a basic content, built-in function, built-in module --> in memory

# sys.path system path import
# import os,sys

# import sys
# print(sys.argv) # The first item in the list is the path where the current file is located

# import sys
# user = input('>>>')
# pwd = input('>>>')
# if user == 'alex' and pwd == '3714':
# print('Login successful')
# else:
#     sys.exit()
# print('What I can do')
# import sys
# if sys.argv[1] == 'alex' and sys.argv[2] == '3714':
# print('Login successful')
# else:
#     sys.exit()

# import logging
# num = int(input('>>>'))
# logging.debug(num)
# a = num*100
# logging.debug(num)
# b = a - 10
# logging.debug(num)
# c = b + 5
# print(c)

# import sys
# import logging
# inp = sys.argv[1] if len(sys.argv) > 1 else 'WARNING'
# logging.basicConfig(level=getattr(logging,inp))
# num = int(input('>>>'))
# a = num * 100
# logging.debug(a)
# b =a - 10
# logging.debug(b)
# c = b + 5
# print(c)

rondom module (random) to shuffle the order

# print(random.random()) # 0-1 random decimals
# print(random.uniform(1,4))

# print(random.randint(1,1000)) # contains 1,2
# print(random.randrange(1,2)) # does not contain 2
# print(random.randrange(1,20,2)) # contains all odd numbers

# print(random.choice([1,'23',[4,5]]))

# print(random.sample([1,'23',[4,5]],2))

# item=[1,3,5,7,9]
# import random
# random.shuffle(item)
# print(item)

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